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Transcript of Riley 2.5_A
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ASECTION A
TIlE ENGINE(2~ LITRE)
General Description.
The Lubrication System.
Section No. A. I
Section No. A.2
Section No. A.3
Section No. A.4Section No. A~5
Section No. A.6
Section No. A.7
Section No. A.8
Section No. A.9
Section No. A.IO
Section No. A.l I
Section No. A.12
Section No. A.13
Section No. A.14Section No. A.15
Section No. A.16
Section No. A.17
Section No. A.l8
Section No. A.19
Section No. A.20
Section No. A.21
Section No. A.22
Section No. A.23
Section No. A.24Section No. A.25
Section No. A.26
Section No. A.27
Section No. A.28
Section No. A.29
Section No. A.30
Section No. A.3 I
Section No. A.32
Section No. A.33
Section No. A.34Section No. A.35
Section No. A.36
Section No. A.37
Draining the engine sump.
Removal and replacement of the sump.
Removal and replacement of the oil pump.
Dismantling and reassembling the oil pump.
The oil pressure release valve.
Removal and replacement of the main bearings.
Removal and replacement of the cylinder head.
Removal of piston and connecting rod.
Removal a!ld replacement ofthe piston rings.
Fitting the gudgeon pins and reassembling piston and connecting rod.
Removal and replacement ofthe carburetters.
Removal of the inlet manifold.
Removal of the exhaust manifold.
Removal and dismantling of the water pump.Setting the tappets.
Removing the dynamo belt.
Removal of the crankshaft pulley.
Removal of the timing chain cover.
Removal of the crankshaft chain wheel.
Removal and replacement of the timing chain.
Removal of the chain tensioner.
Removal of a camshaft.
Removal of the rocker gear.
Removal of the valves.Removal and refitting of the valve guides.
Decarbonising.
Grinding and testing the valves and their seatings.
Adjusting the fan belt.
To dismantle the fan assembly.
Removal and replacement of the engine and gearbox.
Removal of the clutch.
Removal of the flywheel.
Removal of the crankshaft.
Oil pressure.
Regrinding the crankshaft.
Locating troubles.
Piston sizes and cylinder bores.
A. I
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A TIlE ENGINF~GENERAL DESCRIPTION
The four-cylinder, overhead valve engine is built inunit construction with a four-speed gearbox.
It has a robust four-throw crankshaft carried inthree main bearings which are thick white-metal-lined bronze shells dowelled in the crankcase. Therear bearing takes the end thrust, the bearing beingflanged at both ends.
The connecting rod big-ends are white-metalleddirect and the gudgeon pin is a floating fit in the littleend, being retained by circlips.
The pistons are of aluminium alloy and are fitted
with two compression and two oil control rings.Each camshaft is supported in three bronze bushedbearings and is driven from the crankshaft by means
of an endless duplex roller chain.The valves are operated from the camshafts via
hollow cylindrical tappets, short, light push-rods and
rockers. Tappet adjustment takes place at the rocker.Cooling is by pump and fan-assisted thermo-syphon
action.
THE LUBRICATION SYSTEMAn illustration of the lubricating system appears
on page A.26.The engine oil is carried in the ribbed aluminium
sump below the crankcase and an oil level dipstickis fitted to the left-hand side of the block. The com-bined oil filler and crankcase breather is also on theleft-hand side at the front of the engine.
The submerged, self-priming, gear-type oil pump isbolted to the under face of the cylinder block and Isdriven by a skew gear on the inlet valve camshaft.
From the pump, oil is delivered by an external pipeto a full-flow filter. From the filter another externalpipe leads to the crankcase side and thence via internal
oilways to the main bearings.
The big-end bearings receive oil by means of oliwaysdrilled in the crankshaft. Camshafts, timing chain androcker-shafts are supplied by means of internal oilwaysdrilled in the crankcase.
The oil pressure release valve is located just behind
the exhaust pipe.
Section A.l
DRAINING THE ENGINE SUMPThe sump on new and reconditioned engines must
be drained and refilled with new oil after the first
500 miles (800 km.) and then at intervals of every~,000 miles (5000 km.). The hexagon-headed drainplug is situated on the right-hand side of the sump.
The oil should preferably be drained when the engineis hot, in which condition the oil flows more readily.
Unless the sump is to be removed and cleaned, itshould be allowed to drain for at least ten minutesbefore the drain plug is replaced. When the sumphas been drained, approximately 14 pints (8 litres) ofoil are required to refill it.
REMOVAL AND REPLACEMENT OF THESUMPTo clean the sump, take out the drain plug and allow
the oil to drain away. The sump is located by sixteenhexagon-headed bolts and spring washers insertedfrom the underside of the flange. Removal of theseallows the sump to be withdrawn. Remove the trayand thoroughly clean the sump with paraffin and a
clean brush.When the sump has been dried, refit the tray and
drain plug.No gasket is fitted on early models, but jointing
compound is used to make the joint. Make sure alltraces of the old compound are removed beforerefitting the sump.
Later models make use of a gasket and a new oneshould be used when replacing the sump on all models.
Section A.3
REMOVAL AND REPLACEMENT OF THEOIL PUMP
Remove the sump as detailed in A.2 and then takeoff the drive shaft top cap located near the top and
just behind the oil filter.Take off the pump flange nuts and washers and thentap the drive shaft down, when the whole pumpassembly,, complete with shaft and gear, will comeaway from its spigot on the crankcase.
(2+ LITRE)
Fig. Al.
The engine drain plug.
SectiolR A.2
A.2
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(2~ LITRE) TIlE ENGINE A
Section A.4
DISMANTLING AND REASSEMBLING
THE OIL PUMPRemove the oil pump as detailed in A.3 and take off
the coarse mesh screen surrounding the pump body.Next, take off the bottom cover and tap the shaft
downwards so that the gear is exposed. Tap thedriving gear down the shaft to a collar to give accessto the retaining split ring and extract the split ringholding the driving gear in position. Pull off the gearwheel and remove the Woodruff key, then pull out
the shaft.
Fig. A.3.Checking the end float on the oil pump gears.
Ensure that the cover-plate and pump body faces
are perfectly clean before reassembling. They form ametal-to-metal joint and no gasket or sealing com pound
must be used.When refitting the cover-plate take special note of
the two dowel pins.
Fig. A.4.
Checking the diametrical clearance between the oil
pump gears and the oil pump body.
The skew gear at the top of the driving shaft is keyed
and pinned in position. The bush is pinned in position.The driven gear is bushed and runs on a spindle
which is pressed into the pump body.To check the gear clearances, the pump body, gears
and shaft should be cleaned carefully and reassembledbefore carrying out the following procedure
I. Measure the diametrical clearance between theteeth of the gears and the pump body (see Fig.A.4). This should not be more than 006 in.(.15 mm.).
2. Check the end float on the gears by placing astraight-edge across the face of the pump body,
and measuring the clearances with feelers, asshown in the illustration (Fig. A.3). This shouldnot be more than .003 irr. (.08 mm.).
Fig. A.2.The cap on the oil pump shaft.
Fig. A.5.Exploded view of the oil pump.
A.3
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(2{ LITRE)A THE ENGINE.Section A.5
THE OIL PRESSURE RELEASE VALVE
This is provided to prevent the building up ofexcessive oil pressure when the oil is cold. It is locatedon the left-hand side of the engine behind the exhaust
pipe.To adjust the release pressure the locknut should be
slackened off and the grub screw turned in the appro-priate direction. Screwing the grub screw inwardsincreases the release pressure.
To dismantle the assembly the large nut must be
unscrewed and the grub screw removed. After thattake out the spring collar, spring and square plunger.The actual valve seating is pressed into the crankcase,but is renewable. The normal oil pressure is 30 lb./sq.in.
at 40 m.p.h. (2.11 kg./cm.5 at 64 k.p.h.).
The release valve seating is removable by tapping thehole in the seating ~ in. B.S.F. and then using a boltand nut for withdrawal purposes.
Adjustingscrew
Fig. A.6.
The release valve assembly.
Section A.6
REMOVAL AND REPLACEMENT OFTHE MAIN BEARINGS
The crankshaft has three main bearings consisting ofthick bronze shells, white-metal lined. They cannot be
changed whilst the crankshaft is in position.The top halves of all bearings are dowelled in posi-
tion, as are the two lower halves of the front andcentre bearings.
To remove the bearings, take out the split pins andremove the castellated nuts. Take off the bearingcaps and lift out the crankshaft, having previously
removed the timing chain as detailed in Section A.20,
the clutch and flywheel as detailed in Sections A.31and A.32, and the pistons and connecting rods as inSection A.8.
New bearings are supplied with a fitting allowancefor line-boring or hand-scraping.
Section A.7
REMOVAL AND REPLACEMENT OF THECYLINDER HEAD
Drain the water from the cooling system by meansof the three taps provided one on the inlet manifold,one on the cylinder block above the starter motor andthe other at the base of the radiator.
Take off the bonnet, as detailed under Section D.2,and the radiator steady rods ; this will provide plentyof clearance. Next remove the bonnet sides as detailedunder Section R.14.
Remove the air silencer, fume extractor pipe,distributor head and ignition harness together with
the aluminium casting forming the air intake betweenthe two carburetters.
Detach the throttle control rod slow-running cable,and the mixture control cable. Disconnect the fuel
line at the T-piece between the two float-chambersand remove the carburetters. Do not disturb theinterconnecting rod between the two throttles.
Take off the inlet manifold, noting the two rubberwashers between the manifold and the cylinder head.These washers should be renewed each time thecylinder head is removed.
Disconnect the two water hose connections, oneat the thermostat and the other at the water pump
inlet. Then unscrew the water temperature controlunit.
Remove the fan and water pump belts (see SectionsA. 16 and A.28), and disconnect the exhaust pipe at themanifold.
Disconnect the rubber hose between the waterpump and the cross-flow pipe and then take off thelatter before removing the exhaust manifold.
Next, take out the sparking plugs and remove bothrocker covers.
Remove all the push-rods by seeing that each valveis closed, and then depressing the spring with a lever,at the same time moving the rocker to one side. Mark
the push-rods so that they can be replaced in thepositions from which they were removed.
Slacken each cylinder head holding-down nut a slight
amount and then remove them all. Lift off the headand the gasket.
The cylinder head is now ready for decarbonisation2nd valve grinding, as detailed in Sections A.26 and A.27.
A.6
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(2{ LITRE)TUE ENGINE A
Replacement of the head is a reversal of the aboveprocess, but the holding-down nuts must be tighteneddown gradually in the sequence shown in the diagramFig. A.7.
~I2K Fig. A.7.Sequence fortightening thecylinder head
stud nuts.
If a torque spanner is used, the correct tighteningfigure is 900 in./lb. (10.35 m./kg.).
On some earlier cylinder heads the brass insertin the upper transfer port of the hot spot is a loosefit. The open side of the insert must always face thefront of the engine.
The baffle tube fitted across the head and inside the
lower port is renewable.
Section A.II
REMOVAL OF PISTON AND
CONNECTING ROD
The big-end will not pass up the cylinder bore,neither will the piston pass the crankshaft.
The procedure, when it is desired to remove thepiston and connecting rod assemblies, is as follows
Remove the cylinder head as detailed in Section A.7.
Drain the engine sump as explained in Section A.l.Remove the sump as detailed in Section A.2.Take out the split pins and remove the castellated
nuts from the big-end bearing bolts. Take off thebearing cap, which is marked to line up with theconnecting rod. Remove the fixing bolts and push the
connecting rod up the cylinder bore until the gudgeonpin isiust clear of the top face of the block.
Remove a circlip and tap out the gudgeon pinwith a drift, taking care to support the piston at thesame time, otherwise the connecting rod may be bent.The piston can then be withdrawn upwards from the
cylinder, and the connecting rod downwards throughthe crankcase.When refitting the pistons to the bores, use some
form of piston ring compressor in order to prevent
ring damage.
Section A.9
REMOVAL AND REPLACEMENT OF THEPISTON RINGS
If no special piston ring remover is available, usea piece of thin steel such as a suitably ground hacksawblade, or disused ~020in. (.50 mm.) feeler gauge.
Raise one end of the ring, and insert the steel stripbetween ring and piston. Rotate the strip round thepiston, applying slight upward pressure to the raised
portion of the ring, until it rests on the land abovethe ring groove. It can then be eased off the piston.
Do not remove the piston rings downwards over theskirt of the piston.
Before fitting new piston rings the grooves in thepiston must be scraped clean of any carbon deposit,taking care not to remove any metal, since playbetween the ring and the groove reduces gas tightnessand produces a pumping action leading to excessiveoil consumption. There must be no play between the
rings and their grooves but they must nevertheless befree to move without restriction.
Important.—New rings should be tested in thecylinder bore in order to check for correct clearance at the ends.
To do this effectively the piston should be inserted
approximately I in. (2.5 cm.) down the cylinder and each ring then pushed down on to the top of the piston and held there in order to keep the ring square with the bore.
The end gap should be between ~008in. and .012 in.(.2 mm. and ~3mm.).
Fig. A.8.
Checking the piston ring gap.
A.7
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Riley I{ and 2{ Litre. Issue 2 (E) 78538—4/53 A.9
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(2-b LITRE)A THE ENGINESection A.1O Section A.13
FITTING THE GUDGEON PINS AND
REASSEMBLING THE PISTON AND
CONNECTING ROD
The piston and connecting rod are replaced bypartly inserting the piston in the cylinder from the
top and introducing the connecting rod upwardsfrom the crankcase. The two are then coupledtogether by the gudgeon pin.
The gudgeon pin is a push fit in the little-end and
a light drive fit in the piston at room temperauire.Gudgeon pins ~002in. oversize (Part No. 166516) areavailable and may be fitted to take up slack in thesmall end bushes or pistons, which must of course
be reamed out to suit. The gudgeon pin circlipsshould be fitted with a special pair of peg-nosed pliers.
Take care when tapping the gudgeon pin intoposition in the piston to support the piston adequately
so as not to damage it or the connecting rod.
Section A.11
REMOVAL AND REPLACEMENT OF THECARBURETTERS
Detach the forward end of the bonnet release rodand then take off the bonnet side by undoing the nutand bolt at the forward end and the two screws at therear. See Section R.14.
Take off the ignition harness and remove the airsilencer. Remove the cast aluminium air intakebetween the carburetters. The forward end is heldby set screws, the rear by nuts and studs.
Disconnect the fuel line at the T-piece between thefloat-chambers and detach the rich mixture control
cable from both carburetters.Remove the throttle control rod from the rearcarburetter and undo the set screws holding the handthrottle cable at the quadrant. Undo the four nutsand take off the carburetters.
Section A.12
REMOVAL OF THE INLET MANIFOLD
Remove the carburetters as detailed in Section A.l I .Drain the cooling system by means of the three
drain taps (see Section A.7).
Undo the six nuts holding the manifold in positionand then withdraw the casting over the studs.
Renew the two rubber sealing washers, and whenreplacing make quite sure the open end of the brassferrule in the cylinder head is pointing forward.
REMOVAL OF THE EXHAUST MANIFOLD
Drain the cooling system and remove the coolingwater inlet pipe. Disconnect the exhaust pipe at themanifold, undo the retaining nuts, and then take offthe manifold.
Section A.14
REMOVAL AND DISMANTLING OF THEWATER PUMP
To detach the pump, the dynamo and fan belts mustbe removed by slackening back both adjustments.See Section A.28 for the fan and Section A.16 for thedynamo.
It is not necessary to remove the pump body from
the cylinder head because the bearing housing com-plete with pulley and impeller may be taken out byremoving four set screws and washers. Note that onescrew breaks into the waterway, and when refitting,a copper washer is necessary under the screw head.
Fig. A.9.
The water pump partially dismantled.
If the pump body and thermostat are separated,
note the rubber ring and adaptor between the thermo-stat housing and the pump body which forms the by-
pass port. The rubber ring, between the water outletelbow and the cylinder head itself, should also benoted. These rubber rings must be in good conditionand should be renewed if any doubt exists as to theirserviceability.
A. 10 Riley 1+ and 2~ Litre. Issue 2 (E) 78538—4/53
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(2+ LITRE) TIlE ENGINE ATo dismantle the pump, take off the brass Simmonds
nut holding the impeller, draw off the impeller andextract the Woodruff key.
Lift off the spring, the collar, the rubber seal andthe carbon disc and then take out the driving peg forthe carbon disc. If the rubber seal is at all swollen itmust be renewed, otherwise water circulation maybe impeded and the engine tend to overheat.
Next lift off the sealing plate and remove the
Simmonds nut at the other end of the shaft. Draw offthe driving pulley, which is held by a Woodruff key.There is a felt washer behind the pulley which mustbe taken off if it remains on the pump body before
the shaft is pressect out towards the rear ofthe pump.The shaft will come out with the rear lipped oil seal
and packing ring, together with the ball bearings,inner distance tube and the inner race and rollers ofthe front bearing. The outer race of the front bearing
Section A.15SETTING THE TAPPETS
Remove the ignition harness and the small inter-connecting breather pipe from the rocker covers.Take off the rocker covers and this will expose therockers and their adjusters.
The tappets are set by slackening back the locknutand screwing the ball-ended adjuster in or out asrequired. Set the clearance to .003 in. (.08 mm.) inletand .004 in. (.10 mm.) exhaust with the engine hot.
is pressed into the housing from the rear. The distance-piece between the outer races can be lifted out. If itis necessary to remove the outer race of the frontbearing this can be accomplished by levering it outwith a thin screwdriver blade.
When reassembling the bearing and pulley assemblyto its housing, note that the lower set screw on theleft-hand side (facing forward) has a copper washer,because this hole breaks into a water passage.
Section A.16
REMOVAL OF THE DYNAMO BELT
Remove the fan belt by releasing the fan spindleclamp bolt and moving the spindle towards the pump
pulley, then slacken the dynamo belt by releasing thethree dynamo attachment bolts and moving thedynamo towards the engine.
Rotate the fan pulley to its lowest position by
Fig. A.lO.This is a section of the water pump, whilst inset showsthe modification to the water seal on later pumps.
A. II
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(24 LITRE)A THE ENGINF
Fig. A.I I.
The method of removing the dynamo belt by undoingbolts A and B.
slackening the pinch bolt and using a small bar in theholes provided.
To save jacking up the engine, remove one enginemounting bolt at a time on the dynamo side of theengine. This will allow the belt to slip past the mount-ing. Note that one bolt carries the dynamo steadyarm and the other a distance-piece.
Section A.17
REMOVAL OF THE CRANKSHAFT
PULLEY
Take out the bolt through the pulley and its fixingnut. Unscrew the nut, which has a’ right-hand thread,and withdraw the pulley, which is on a parallel shaftwith a Woodruff key.
Section A.18
REMOVAL OF THE TIMING CHAIN COVER
Remove the dynamo belt and crankshaft pulley as
indicated in Sections A.16 and A.17.There are fifteen nuts and spring washers holding
the timing cover to the block and in addition there isone set screw at the bottom which secures the sump.
Also, between the engine mounting and the dynamothere is a countersunk screw.
There is a Simmonds nut, a steel washer and a corkdisc in the centre of the cover which must be removed.The cover can then be lifted off and there is no gasketat this joint.
Note the position of the oil return ring and the oilthrower ; the latter has the dished portion towardsthe engine.
Section A.19
REMOVAL OF THE CRANKSHAFT CHAIN
WHEEL
Remove the dynamo belt, crankshaft puijey andtiming cover as indicated in Sections A.16 to A.18.
Remove the timing chain as explained in Section A.20and draw off the wheel, which is on a parallel shaft witha Woodruff key, using a suitable extractor, ST.58, toavoid damage.
Section A.20
REMOVAL AND REPLACEMENT OF THE
TIMING CHAINTake off the timing cover and crankshaft puliey.
Then wedge the tensioner wheel in its extreme
Fig. A.12.This illustration shows the tensioner wedge and the camshaft
bush which is partially withdrawn from the crankcase.
A.14
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(2+ LITRE) -THE ENGINE Aposition, with the ratchets removed, so that the chainfalls slack. Undo the lock washer and set screwholding one of the camshaft chain wheels and thenwithdraw the wheel. The chain may then be lifted off.Although the chain wheels are marked for timing, itis a wise plan to polish two of the chain links to
correspond with marks scribed on each chain wheelthis will considerably help chain refitting. If a newchain is to be used, mark the old one and use it asa guide for the new.
Before marking the old chain, first make sure it isnot already marked, to avoid confusion. Remember
that the marked chain links only coincide with themarked teeth of the chain wheels once in every104 revolutions of the crankshaft.
Fig. A.13.The setting ofthe crankshaft and camshafts for correct valvetiming. Notethe keyway onthe crankshaft, the timing marks
on the camshaft sprockets and the marked chain links.
Section A.21
REMOVAL OF THE CHAIN TENSIONER
Remove the dynamo belt, crankshaft pulley andtiming cover as explained in Sections A.16 to A.18.Take off the ratchet portion of the tensioner andwithdraw the wheel, taking care not to lose thespring. The square stub upon which the wheel slides
is held to the cylinder block by countersunk screws.One of the ratchet plates on the adjuster is pro-
vided with slotted holes so that when the tension of
the timing chain is set the plungers are located sothat while one is at the bottom of the ratchet tooththe other rests on the top of a tooth on the otherplate. Thus the slightest amount of wear in the chainwill be taken up immediately.
Section A.22
REMOVAL OF THE CAMSHAFTS
Take off the engine pulley, timing cover and timingchain as described under Sections A.16, A.18, and A.20.Remove the cylinder head as indicated in Section A.7.
Lift out the tappets from the top, making sure thateach is marked for subsequent reassembly in the sameposition.
Remove the camshaft chain wheels as indicated inSection A.20.
With the chain wheels removed, undo the set
screws which hold the camshaft and front bearingassembly to the block (see Fig. A.12). The camshaftis then ready for removal. In the case ofthe exhaustcamshaft the distributor must first be removed (seeSection C.7).
Section A.23
REMOVAL OF THE ROCKER GEAR
Take off the ignition harness and remove -thebreather pipe and rocker covers.
Depress each valve in turn, move the rocker aside
and extract the push-rods. Undo all the securing nutsfor the rocker pedestals and lift the assembly awaycom plete.
The rockers are bushed and of two types, left-handand right-hand. Each rocker-shaft is in four sections
carried in five pedestals, the sections being locatedby set screws on the second and fourth pedestals, thefront and rear of which are not Interchangeable witheach other or side for side. They are drilled for rockerlubrication, the oil passing up a hollow stud. Note thatflats are machined on the rocker-shafts. These flatsmust face towards the valves.
Section A.24
REMOVAL OF THE VALVES
The valve springs are retained in position on thevalves by means of a collar and two split collets.
Fig. A.14.
Valve spring compressor.
A.15
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A THE ENGINESupport the head ofthe valve inside the combustionchamber, apply a suitable compressor to compress the
spring and cap, and the collets may be removed.The valve springs are not of constant pitch and must berefitted with the close-coiled end at the bottom.
Section A.25
REMOVAL AND REFITTING OF THE
VALVE GUIDES
The valve guides are interchangeable and quite
plain, without any shoulder. They may be tapped outwith a drift, and when fitting a replacement guide thenew one should be pressed in until the top is j~ in.(20.64 mm.) above the spring seat for both inlet andexhaust. The extra length of the exhaust valve guideshould project into the valve port.
Fig. A.15.
A special tool may be made for fitting the valve guidescorrectly.
Section A.26
DECARBONISING
Remove the cylinder head as explained in Section A.7.
Take out the valves as indicated in Section A.24.Lift off the cylinder head gasket, and plug all water
holes and the tappet guides with cloth plugs.Scrape the carbon off the piston crowns, cylinder
heads and inlet and exhaust ports. Take care that thepistons are not scratched by the use of a sharp tool.
It is also advisable to polish the combustion chambers with emery cloth, but great care must be taken toclean away all traces of abrasive dust.
Never use emery cloth on the piston tops because
small abrasive particles will undoubtedly find theirway into the cylinder bores.
A ring of carbon should be left on the periphery ofthe piston crowns by placing a piston ring on the top,and the carbon round the top of the cylinder boresshould also be retained intact.
Remove all traces of dust by means of compressedair and then clean well with paraffin. Always use anew cylinder head gasket after decarbonising.
Section A.27
GRINDING AND TESTING THE VALVES
AND THEIR SEATINGS
Remove the valves and springs as detailed inSection A.24.
Clean each valve carefully and examine the seatingfor signs of pitting. If pitting is apparent then the valvemust be refaced. The same applies to the valve seats
and great care must be taken not to remove too muchmetal.
Fig. A.17.
The numbering of the valves is shown in this illustration.
(2+ LITRE)
Fig. A.16.
Removing the carbon.
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THE ENGINE AEach valve must be replaced in the same port from
which it was removed, and when grinding in the facesa fine or medium grade carborundum paste shouldbe used.
Place a light coil spring under the head of the valveand use a suction-type grinding tool to impart areciprocating motion to the valve.
An even matt finish is desirable, and if the seat is toowide it should be reduced to approximately 080 in.(2 mm.) by means of a 450 cutter.
After having ground in each valve, the ports,seatings and valve itself should be carefully cleanedwith paraffin and then dried, taking care that no trace
of grinding paste finds its way into the valve guides.
Section A.28
ADJUSTING THE FAN BELT
The fan belt tension is altered by slackening back thefan spindle pinch bolt and rotating the fan hub assemblycompletely round in the engine mounting bracketby means of a bar inserted in the holes on the hub.
#/
Fig A.18.
The fan belt adiustment.
Section A 29
TO DISMANTLE THE FAN ASSEMBLY
Undo the pinch bolt holding the fan hub assemblyto the engine mounting bracket and remove theassembly complete.
Remove the fan blades.Unscrew the lock-ring at the rear end and tap out
the shaft complete with rear bearing, distance tubeand the front bearing.
The outer race of the front bearings stays in thehub and is prevented from moving towards the frontend by means of a distance tube between this outerrace and the fan end plate.
The locking ring at the rear end carries an oil seal.When reassembling take care that the rollers of the
front bearing enter the outer race squarely, otherwiseassembly will not be possible.
Section A.30
REMOVAL AND REPLACEMENT OF
THE ENGINE AND GEARBOXDisconnect the battery.Drain the cooling system as described in Section
D.l.Remove the bonnet tops (Section D.2) and sides as
explained under Section R.l-4.Disconnect the water temperature unit at the
thermostat and remove the radiator stays.Ren~ove the radiator and shell as explained under
Section D.2.
Disconnect the cable from the coil to the distributorand remove the coil from the frame.
Remove the wire stay between
the frame
andforward engine mounting.
Take off the air filter and carburetters as explainedin Section A.l I. Take off the cables to the dynamoand starter motor and disconnect the exhaust pipeat the manifold. Then remove the dipstick.
Slacken the dynamo adjusting bolts and push the
instrument inwards and place a single rope slingaround the middle of the engine. Then take off themounting plate on the front of the engine and thebracket shown in Fig. A.19.
(2{ LITRE)
Fig. A.19.
Method of removing the mounting.
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(2+ LITRE)A THE EN1~lWUnscrew the union on the oil pressure gauge line
and uncouple the throttle control rod at the bellcrank on the side of the block.
Slide both front seats right back and remove themfrom the car. Then remove the carpets and unscrewthe knob on the gear lever.
Remove the gearbox cowl by sliding back theforward catches and unscrewing the small plate at therear. Then take up the floorboards.
Disconnect the front end of the intermediate driveshaft and unscrew the reversing light cables from theswitch unit on top of the gearbox. Remove thespeedometer drive gear from the gearbox and undo
the nut on the wire stay.
Fig. A.20.
The method of disconnecting the intermediate shaft.
Extract the pin on the clutch cross-shaft universal joint and then remove the gear lever complete bylifting out the spring ring in the gear lever ball housing
and the two set screws at either side. When liftingthe lever out, take care not to lose the small spring-
loaded ball in the crank.Take out the rear mounting bolts under the gearbox
and then the complete gearbox and engine unit maybe tilted downwards and drawn out to the front.
Assembly is a reversal of this process, but note thatthe thick rubber buffers under the radiator must beabove the mounting and the thin ones below. Tightenthe. Simmonds nuts sufficiently to just nip the rubber.
Tighten the unit mounting bolts fully and seethatthesteady cables at the front and rear are just in tension.
Section A.31
REMOVAL OF THE CLUTCH
Take off the gearbox as described in Section F.l.Slacken back the retaining screws holding the
clutch cover-plate to the flywheel. The screws shouldbe undone evenly a turn at a time and diagonallyto prevent the spring pressure straining the clutchcover-plate.
Fig. A.21.
The method of lining up the clutch when refitting it tothe flywheel.
Section A.32REMOVAL OF THE FLYWHEEL
Take off the gearbox as explained in Section F.l.Detach the clutch as in Section A.31.Bend back the locking tabs and unscrew the eight
fitted bolts. The flywheel, complete with cast-ironfriction face, may then be either drawn or tapped offits spigot on the crankshaft.
Fig. A.22.
The flywheel run-out should not exceed .004 in. (.1 mm.).
7)~
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(2+ LITRE) THE ENGINE ASection A.33
REMOVAL OF THE CRANKSHAFT
Take out the engine unit as described in Section
A.30.Drain and remove the sump as indicated in Sections
A.l and A.2.
Take off the gearbox. (See Section F. I.)Remove the clutch and flywheel as described in
Sections A.3 I and A.32.Disconnect the connecting rods from the crank-
shaft. (See Section A.8.)
Remove the crankshaft pulley. (See Section A.17.)Take off the timing chain cover (Section A.18) and
remove the timing chain (Section A.20).Take out the split pins from the main bearing cap
nuts and undo the nuts.
Lift off the bearing caps, noting that they are
marked for subsequent correct assembly, and detachthe split sealing plate at the rear. This is held by twolong screws with tapered heads.
Lift out the crankshaft.
Section A.34
OIL PRESSURE
Under normal running conditions the oil pressureshould not drop below 40 lb./sq. in. (2.8 kg./cm.
2) on
the gauge, whilst approximately 12 lb./sq. in. (.9 kg.!cm.2) should be shown when the engine is idling.
Should there be a noticeable lack of pressure, thefollowing points should be checked over
I. That there is a good supply of the correct gradeof oil in the engine sump.
2. That the pump gears are in order and have thecorrect clearances. (See Section A.4.)
3. That the gauze oil pump filter is clean and notchoked with sludge.
4. That the bearings on the delivery side to whichoil is fed under pressure have the correctworking clearances. Should the bearings be
worn and the clearances excessive, the oil willescape more readily from the sides of thebearings, particularly when the oil is warm
and fluid. This will cause a drop in the pressurerecorded on the gauge, as compared with thatshown when the bearings are in good order.
Note.—.The automatic release valve deals with any excessive oil pressure when the engine and oil are cold.
Cold •running and unnecessary use of the mixturecontrol are often the cause of serious oil dilution by fuel,and of a consequent drop in pressure.
New engines with new oil will produce considerably higher pressure readings than those given.
Particular attention is called to the recommended change of oil every 3,000 miles (5000 km.). This is a most important factor in attaining long and trouble-free service from the engine.
Section A.35
REGRINDING THE CRANKSHAFT
Crankshafts are provided either .020 in.(—.50 mm.) or —~040 in. (—1.1 mm.) undersize on
the main bearings with standard size big-ends and
—~020 in. (—.50 mm.) or —.040 in. (—1.1 mm.)undersize on the main bearings with either .020 in.(—.50 mm.) or —~040 in. (—1.1 mm.) undersize big-
end bearing journals.
Section A.36
LOCATING TROUBLES
Engine will not start A. If the starter will not turn the engine, check the
following
I. Battery discharged, and/or defective.
2. Disconnected or broken leads.3. Faulty starter switch.4. Faulty starter motor.5. Starter cables shorting to earth.
Fig. A.23.
The split sealing plate.
Riley 1+ and 2~ Litre, Issue 2 (E) 78538.—4/53 A.2 I
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A.22 Riley l{ and 2+ Litre. Issue 2 (E) 78538—4/53
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(2+ LITRE) THE ENGINE A6. Battery terminals badly corroded or battery
leads loose.
B. If starter turns engine very slowly, checkI. Partly discharged battery.
2. Loose terminals or connections.3. Dirty or corroded connections.4. Faulty insulation on starter cables.5. Tightness in engine.6. Faulty starter brushes.
C. If starter turns engine smartly, but it will not fire,check
I.
2.
Plugs not sparking.
Spark at the coil. If the coil gives a goodspark, check
(a) Gaps in plugs too wide or too close.
(b) Plugs oiled up.(c) Plug insulators damaged, or excessively
dirty.
3. If poor spark at coil, check
(a) Low-tension or high-tension leads from
coil to distributor loose or corroded.(b) Distributor points dirty, worn or out of
adjustment.
(c) Carbon brush not making contact.(d) Rotor cracked.(e) Faulty condenser (substitute a condenser
known to be in order).
(f) Faulty coil (substitute a coil known tobe in order).
4. Check the carburetters for fuel supply. If nofuel in the float-chambers, check(a) Functioning of the fuel pump.(b) Air leak in pipe line, indicated by rapid
action of the pump.(c) Float-chamber needles sticking.
5. If fuel is reaching the float-chambers, check(a) For choked jets.(b) Water in the fuel.(c) Dirt in the carburetters.
(d) Air leak in induction system.(e) Check adjustment of carbu retter controls.
If engine starts, but runs erratically A. Check the following ignition points
I. Loose high-tension leads to sparking plugs.
2. Incorrect setting of plug points.3. Damaged plug or moisture on plugs.
4. Loose connection on battery or in ignitioncircuit.
5. Faulty high-tension leads.6. Battery charge low.
7. Battery connections faulty.8. Defective contact breaker.9. Defective distributor.
10. Faulty condenser.
B. Check the following carburetter pointsI. Water in float-chambers.
2. Choked filters in carburetters or fuel pump,indicated by slow pumping of fuel pump.
3. Action of fuel pump. Suspect if sluggish.4. Jet partially choked.5. Carburetter or carburetters
indicated by sooty exhaust.6. Vents on fuel tank filler caps choked.7. Obstruction in fuel feed pipe.
8. Air leak into induction system.
set too rich,
C. Check the following mechanical points
I. Sticking valves.2. Incorrect valve clearance.3. Burnt or broken valves.4. Incorrect valve timing.5. Incorrect ignition timing.6. Broken or weak valve spring.
7. Valve guides worn, causing air leaks.8. Cylinder head gasket for leaks.9. Back pressure due to damaged exhaust
system.
lf engine starts and stops A. Check the following ignition points
I. Loose low-tension leads.2. Loose distributor clamp screw.3. Faulty ignition switch contact.
B. Check the following carburetter pointsI. Incorrect setting of carburetter controls.
2. Blocked fuel pipe.3. Water in float-chambers.4. Sticking.needle valve.5. Fuel pump failing to function regularly.6. Air leak into fuel line.7. Fuel level low in tank.
If engine will not idle or run slowly A. Check the following carburetter points
I. Throttle stop screws incorrectly set.
2. Hand throttle control requires adjustment.3. Throttle controls incorrectly set.4. Weak mixture or over-rich mixture.5. Faulty functioning of fuel pump.
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A TIlE ENGINEB. Check the following mechanical points
I. Sticking valves.2. Incorrect valve tappet clearance.3. Air leak in induction system.4. Burnt or broken valves, indicated by loss of
compression.5. Broken valve spring.6. Damaged cylinder head or gasket.
C. Check the following ignition pointsI. Loose high-tension leads.
2. Incorrect setting of plug points.3. Damaged plugs or moisture on plugs.4. Loose connections on battery or in ignition5. Faulty high-tension leads. [circuit.6. Battery charge low.7. Battery connections faulty.8. Defective contact breaker, or burnt points.
9. Defective distributor.10. Defective condenser.
Engine fails to gi.ve full power A. Check the following carburetter points
I. Faulty or insufficient fuel supply.2. Air leaks in induction pipe or fuel pipe.3. Partly choked jet or jets.
B. Check the following mechanical points
I. Incorrect valve tappet clearance.2. Burnt valve or badly seating valve.3. ~Cylinderhead stud nuts not tight.4. Damaged cylinder head gasket.5. Valve timing incorrect.6. Broken or weak valve spring.
7. Excessive carbon deposit.8. Excessively worn pistons and cylinders.
C. Check the following ignition pointsI. Ignition retarded too far.
2. High-tension leads shorting, or loose.3. Dirty sparking plugs.4. Sparking plug points incorrectly set.5. Contact breaker points incorrectly set.6. Contact breaker points pitted.7. Faulty coil.8. Faulty condenser.9. Low-tension connection or leads faulty.
JO. Battery run down or faulty.
Engine knocks A. Check the following
I. Ignition timing too far advanced.
2. Excessive carbon deposit.3. Fuel unsuitable or mixture weak.4. Loose or worn bearings or pistons.5. Defective or unsuitable plugs.6. Valve timing incorrect or tappet clearance
incorrect.
Engine backfires A. Check the following ignition points
I. High-tension cables defective or connectionsloose.
2. High-tension leads incorrectly fitted.
3. Low-tension wiring defective or connectionsloose.
4. Switch contact faulty.5. Distributor gap incorrect or points pitted or
dirty.6. Contact breaker arm sticking or defective.
7. Distributor cover cracked or loose.8. Distributor not correctly timed.
9. Rotor carbon brush pick-up defective orworn.
10. Clearance between rotor arm and distributorstuds excessive.
II. Coil defective or wet.12. Defective condenser.13. Plugs overheated, unsuitable, or points in-
correctly set.
B. Check the following carburation pointsI. Jets choked or restricted.2. Jets incorrectly set, causing weak mixture.3. Water in fuel.
4. Choked fuel filters.5. Inlet manifold joint leaking, or manifold
cracked.6. Air cleaner passages blocked.
7. Engine running temperature too cold.8. Throttle not closing completely (indicated by
engine backfiring when proceeding downhillwith throttle shut).
C. Check the following mechanical pointsI. Valve timing incorrect.
2. Valve tappet clearance incorrectly set.3. Valve sticking.4. Valve seats pitted or faulty..
5. Valve spring weak or broken.6. Valve guides excessively worn, causing air
leaks.
7. Excessive carbon deposit.
(2+ LITRE)
A.24
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TIIF ENGINE A
PISTON SIZES AND CYLINDER BORES
It is necessary to fit new pistons by selectiveassembly, and to facilitate this the pistons are markedon their crowns with identification figures which mustcorrespond with those of the cylinders to which theyare fitted.
The actual bore dimensions of each cylinder arestamped on the top face of the cylinder block on thefront right-hand corner by the appropriate symbol
S.T.D., indicating that the cylinder bore is ofstandard diameter, i.e. possesses an actual diameterof 3~l693 in. (80.5 mm.).
+0005, indicating that the cylinder bore is oversizeto the extent of -i-.0005 in., and thus possesses anactual dimension of 3.1698 in. (80.5125 mm.).
+~00l, indicating that the cylinder bore is oversizeto the extent of -f-~00l in. and thus possesses anactual dimension of 3~l703 in. (80.525 mm.).
±~00l5,indicating that the cylinder bore is oversizeto the extent of +~00l5 in. and thus possesses anactual dimension of 3~l708 in. (80.5375 mm.).
The pistons are marked with the actualcylinder bore size, the requisite running clear-
ance being allowed for in the machining.Thus those marked -V00l in. should be fitted to
bores marked ~~00l in. and so on throughout therange covered.
When the cylinder head is removed and the pistonswithdrawn, the cylinder bores should be measuredfor wear, Indication that a rebore of the cylindersis necessary is given by general loss of performance,oiling up, and poor compression, and is confirmed bymeasurement of the bores.
Rebores
Four ranges of rebore sizes are provided andcylinders must only be rebored to one of these sizesto ensure the supply of the correct pistons.
To provide the normal machining tolerance, oversizepistons are available which are •0005 in., ~00l in. and
in• diameter 025 mm. and ~O375mm.) largerThe four standard oversizes for rebores are
+~0l0 in. (.25 mm.) [actualbore 3.1793 in. (80.75 mm.)]±~020in. (.50 mm.) [actualbore 3.1893 in. (81 mm.)]+~030 in. (.75 mm.) [actualbore 3~ 1993 in. (81 ~25mm.)]±~04Oin. (1.00 mm.) [actualbore 3~2093 in.(81.5 mm.)]and oversize pistons are available for the above rebore
sizes in the following range H-0005 in., +~00l0 in.,+~00l5 in..
There are thus twenty piston sizes available forreplacement purposes as tabulated.
Piston marking Bore size
To suit 3~l693 in. to
standard bore 3.1697 in.
To suit 3.1698 in. to
+~0005 in. bore 3~l702 in.
To suit 3~l703 in. to
±~00l0in. bore 3.1707 in.
To suit 3~l708 in. to±~00l5in. bore ‘3.1712 in.
1st Oversize (±010in.)
Piston marking Bore size
To suit 3.1793 in. to
±~0l0in. bore 3.1797 in.
To suit 3~l798 in. to
+~0l05 in. tore 3.1802 in.
To suit 3~l803 in. to
±~0l10 in. bore 3.1807 in.
To suit 3~l808 in. to
±0l Sin, bore 3.1812 in.
2nd Oversize (±~020in.)
Piston marking Bore size
To suit 3~l893 in. to
±~020in. bore 3~l897 in.
To suit 3.1898 in. to
±~0205in. bore 3~l902 in.
To suit 3.1903 in. to
±~02l0in. bore 3.1907 in.
To suit 3.1908 in. to
±~02l5in. bore 3.1912 in.
(2+ LITRE)
Section A.37 Standard
A.25
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A THE ENGINF3rd Oversize (+030 in.)
Piston marking Bore size
To suit
+~03O in. bore
3~l993 in. to
31997 in.
To suit
+~O305 in. bore
31998 in. to
3~2002 in.
To suit
±~O3lOin. bore
3~2OO3 in. to
3.2007 in.
To suit
±‘0315in. bore
3~20O8 in. to
3.2012 in.
4th Oversize (+~04O in.)
Piston marking Bore size
To suit
+0400 in. bore
3~2093 in. to
32097 in.
To suit
±~0405in. bore
3.2098 in. to
32102 in.
To suit
+~04l0 in. bore
32103 in. to
32107 in.
To suit
+~04l5 in. bore
3~2l08 in. to
3.2112 in.
(2+ LITRE)
I. ‘*-4+