Engine removal and replacement

Engine removal is a serious business and should not be taken lightly. It will require the help of another strong person. The engine unit is heavy m both machines — in the Twin it hangs in the frame and therefore requires careful lowering and in the Triple it has to be lifted at an angle to clear the frame tubes. For the Twin you are going to need a stout wooden box on which to lower the unit, and then a long piece of timber to lever it back in again. The Triple requires nothing more than a piece of wood on which to rest the unit once it is out of the frame. Never place the engine straight onto concrete or similar — never onto grass or earth, either.

If you can get your machine well off the ground, so much the better — a proper motorcycle work bench is best of all. Have plenty of rag available before you start and have a wash tray readily to hand, to clean components as they are removed. This tray should have a petrol-paraffin mix or a proprietary degreaser/cleanser m it. Have somewhere where you can label and store the parts — you'll never remember them at when you come to re-assemble. It's also essential to 'put back' all nuts and washers as they are removed. Remember these machines rely on a very 'close' specification under which to operate efficiently — one shim out of place and you could have a bag of rattles upon re-assembly. The ideal oanditkms under which to operate are those to be found in the best racing shops — clean, light warm, spacious, fully-equipped laboratory. TAKE YOUR TIME AND WORK CALMLY — Laverdas disassemble very easily.

Each dismantling task is described in detail once the engine is removed from the frame, even if some of these tasks could have been carried out with the engine still in the frame. Those 'in the frame' details will be incorporated. Read through the whole procedure before starting . . .

NOTE: Cleaning components as they are removed obviously makes very good sense. Cleaning them again in a different way is even more important when you are assembling them. Nothing can ever be too clean. Many cleansers can be used — petrol, methylated spirits, WD40 and degreaser — but one of the best, for final cleansing, is warm soapy water. Do make sure you rinse and dry the parts thoroughly and if you have washed steel, make sure it does not go rusty.

Never shot blast any components of a Laverda unless you want to pit the surface metal. Bead blasting is fine for the cast alloy components of the engine but remember to thoroughly clean them afterwards for the beads will lodge in drillings and crevices and may possibly cause further problems such as oil blockage. Never bead blast the polished internal or external surfaces. Twin

Many tasks can be tackled with the engine still in the frame but because of the method used to fix the engine to the frame, these tasks can be divided into two. The first type of task are those that can be undertaken with the engine fully fixed — these consist of: Primary drive and clutch complete, and oil pump

Dynamo, starter motor and starter freewheel Gear change but not selection system, gearbox sprocket Carburettors, coils and ignition system complete Cylinder head tightening

The second type of task are those which require the engine to be loosened at the cylinder head on which it hangs, and hinged in the frame at the gearbox, but not full removal — these consist of: Cylinder head, valves and camshaft, and camchain (admittedly easier with the engine out of the frame)

Barrel, pistons and piston rings

All other tasks require complete engine removal.

Sit the machine on its centre stand. Disconnect the battery, remove the fuel tank and seat (if it is the removable sort). Remove the fairing of SFCs. Drain the engine oil, and on the SFC remove the oil cooler and its pipes (if fitted). Remove the exhaust system complete — on the pre-1973 system you can remove each side complete, once you have disconnected the balance pipe (if fitted). On the 'big' system you can leave the two silencers but this does not ease refitting, therefore, it's better to < remove it all.

Remove the carburettors. Take the slides and chokes out of the top of each carburettor and carefully wrap them in rag and tie them conveniently to the rear, on top of the top frame tubes. The best 'tie-backs' are pieces of PVC-covered wire which you can twist. Remove the clutch cable from the gearbox and carefully tie that back to the top frame tubes.

Disconnect the electrical leads to the horns, and remove just the horn bodies. Remove the rev counter cable from the engine. Make sure you remove the circlipped drive tag. Tie the cable to the front forks.

Loosen the rear chain adjusters, the rear wheel spindle, brake connections, undo the chain and remove it. (Remove the chaincase rubber sleeves, if fitted). Do up the rear wheel spindle again so that you have a stable rear wheel.

Disconnect the following electrical cables and tie them back sensibly: starter motor, dynamo and the neutral selector from inside its cover under the gearbox. Its cover is fixed by two bolts and washers. Replace the little oval cover.

Remove having disconnected the wiring which goes to the ignition contact points at the two snap connectors just above the oil filter dipstick at the frame tube. Remove the plug caps and tie each lead back to the top frame tubes. Place your strong wooden box under the engine crankcase.

Using a good socket set and ring spanners loosen the six connections between the engine and the frame. Once they are all loose, i.e. all the studs still in place but one or both of their nuts and washers removed, remove each one by tapping it through with a hide-headed hammer starting from the top/front of the engine and working to the bottom/rear. The final fixings are two separate nuts and bolts which are difficult to undo. You will probably find that the engine stays 'up in the frame' with all the studs removed until it is 'eased' down. Hinge the engine down onto the box and then finally remove those last two bolts. Then push the whole thing out of the frame and onto the box. You cannot do this last task by yourself — the engine unit is simply too heavy.

Now move the engine away from the frame. Rest it on wood and chock it so that it cannot fall.

Engine replacement is basically a straight reverse procedure but there are a number of helpful points. You will need help from another, possibly two others, to lift and position the engine into the frame, at the engine's lowest and rearmost point first. Once you have got those two bolts into place, you can lever the engine unit with a long piece of hefty timber up into the frame. Replace all the studs, replace all the nuts and washers and do them ALL up finger tight before you attempt to tighten any of them. If you tighten any before they are all placed, you will find that the engine is too tight for the frame.

Progressively and carefully tighten all the fixing points up to a torque of 36-43 ft. lb. Make sure the studs are centred and that there is the same amount of thread free on each side. (On machines fitted with engine crash bars and on the SFC, make sure the bars and the fairing fixings, respectively, are fitted). It will help also to thread the rear chain around the gearbox sprocket before the engine is offered up to the frame. This will save a lot of hassle at a later stage. (It's easier still to remove the gearbox covers).

Triple

Many repairs can be carried out to the Triple engine, clutch and gearbox with the whole unit still sitting in the frame. Remember that the frame design of the Triple is conventional when compared with the Twin and that the engine has to be lifted out rather than 'dropped down'.

With the engine unit still in the frame you can carry out the following work: Primary drive and clutch complete

Alternator, starter motor, starter freewheel and ignition system Gearchange, but not selection system, gea: :»Qx sprocket Carburettors

Cylinder head, valve gear, camshafts and camshaft chain Barrel, pistons and piston rings

All other tasks require the engine to be full;» removed.

Place the machine on its centre stane zram the engine oil and disconnect the battery. Remove the fuel tank and on early machines, the sea: Remove the oil cooler and its pipes down on the crankcase. On late machines, disconnect the electrical connections and remove the horn bodies. In spite of what others may have said, I recommend that you remove the whole exhaust system by splitting off the two silencers and remove the down pipes complete from the exhaust stubs. If you do this, then you will not trip over the har f - - pipes on the frame, you will be able to wheel the frame about easily once the engine is out an; me pipes' chrome is very safe. (You can, however, just pull the down pipes from the exhaust stubs and hang the exhaust system still complete under the frame).

Remove the clutch cable from the gearbcx end and tie it back to the frame. Disconnect the throttle cable at the carburettors and tie that hack. Remove each carburettor's choke and choke cable and tie them all back wrapped in rag Remove the carburettor's intake trunking and then slacken each carburettor on its individual mcate stub. Slide the carburettors back off their stubs and remove them. You may have to juggle the centre carburettor a little and this may eventually mean that you take off its slide cover, held :n by two screws, to clear the top frame tube.

Disconnect the neutral indicator elect?: re . ead under the gearbox. Its fixing is hidden under a rubber plug.

Disconnect the starter motor electrical

Remove the three plug caps and tie bac* me plug leads to the top frame tubes. Disconnect the alternator and magneto cables at the centra, motion box. Record which wire goes where! Remove the rev counter cable from the top of the enpne and tie it back to the forks. Don't lose its little drive peg.

Remove the rear brake pedal from its spline — this just helps! Loosen the rear chain adjusters, the rear wheel spindle, unc: the chain and remove it. (Remove the chaincase rubber sleeves, if fitted). Do up the rear wheel acmd-e again so that you have a stable machine.

Undo all the engine bolts including the two hidden ones at the back of the crankcase. Remove, first, the nuts (only) of the bolts on the s.ce c .ates on the engine, at the front down tubes. Then slacken all the others. Now remove the two side plates complete and then the four rearmost, two are difficult to get at. Very carefully and methodically wrap the two front down tubes of the frame, from the top at the steering head down under the engine with a protective material. Carpet, carpet underlay, rubber matting will all do the trie*. Wrap it and hold it in place with 'racer' or duct tape. If you don't do it well, the engine will take the paint off the frame as you remove it.

Pull the engine forward (or lever it) until it just clears its rear mountings. Here comes the difficult bit. Remove the breather pipe which comes up out of the gearbox. Minimise the damage the exhaust studs might do to the frame.

Start a series of lifting movements to swing the engine at the front up, the rear down, and then the front up and to the right and out of the frame. It's a very tight fit. It may take a couple of goes to get it right — be patient and start from scratch each time you fail.

Once the whole unit is out, place it on a bench or at least on a piece of wood.

NOTE: Machines fitted with left foot (crossover) gearchange will have to take extra care when clearing the rear of the frame because of the crossover shaft which bears on the rear of the gearbox.

Laverda 650 Vicenza

Shown clearly here is one of the rear engine/gearbox mountings on a Triple frame (with the engine removed). Note the rag on the front tube and the bash the frame has had because it did not cover enough tubing

The cam chain tensioner sitting behind the engine leaves little room in which to work. The cover has a second setscrew hidden by the starter motor connection

It makes good sense to remove the adjuster first, before tackling the body

Replacement of the engine is a pretty straight reverse procedure- of its removal. Make sure that the rearmost engine bolts are located first. Feed the rear chain over the gearbox sprocket before replacing the engine.

Although of seemingly very different designs, the Twin and Triple engines, can be discussed in the same breath once you have dismissed the cylinder heads, camshafts and valve gear and oil pumps. Therefore, the next sub-sections deal with the stripping of the 'one' engine, gearbox and clutch unit, but start with two separate parts for the two sets of cylinder head/camshafts/valve gear. The oil pumps will be discussed separately in the appropriate place.

The next sub-sections describe the full disassembly of the engine and gearbox unit, and they do so in a logical fashion. You can stop at any particular point, investigate and repair as necessary and then re-assemble again. In other words, you don't have to strip your engine down to the crankcase halves to get at the oil pump.

This statement is particularly relevant to those people who have gearbox maladies. Although the description feiven here for splitting the crankcase assumes that the cylinder head and barrel is removed, it is not strictly necessary. If you wish to get at the gear trains and selecting mechanism then you can lift the lower crankcase half off the rest of the engine complete. In this case, just turn my description 'upside down'.

Shown clearly here is one of the rear engine/gearbox mountings on a Triple frame (with the engine removed). Note the rag on the front tube and the bash the frame has had because it did not cover enough tubing

The cam chain tensioner sitting behind the engine leaves little room in which to work. The cover has a second setscrew hidden by the starter motor connection

It makes good sense to remove the adjuster first, before tackling the body

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