P6B S Project Car

Am I going to need to pack the oil pump to get it prime, after sitting days without a filter on it? I has leaked some oil, but I dont think its enough to empty it. Probably should do while access is good, just to be sure....
 
Plan - pack oil pump; when its back in the car connect up everything except coil and fuel pump and radiator, crank it to check pressure comes up. If it doesnt the pump will be relatively accessible.
I REALLY dont enjoy getting the throwout lever and sleeve into an LT77 bellhousing!
 
Problem? Much stuff in book about getting correct gear clearance to cover ...and old gasket is badly torn. Not easy to check if gears turn ok once cover is fitted. Suggestions please from those who have pulled pump cover off and refitted with engine place.
 
You need a new gasket. You can check if the gears turn by using a long screwdriver in the distributor shaft hole. However it will only tell you that the gears are not seized. If the cover or gear ends are worn the gap is bigger making the operation poor. So the only way to check is the procedure below.

The end cover is supposed to be surfaced in teflon. Check it hasn't worn away under the gears. The gears sit a tiny bit proud of the casing edge. enough to feel the step with fingers. placing a straight edge across the gears and using feeler gauges between it and the casing edge will tell you how proud the gears are sitting. New gasket material or new made up gasket should come with a compressed thickness notation somewhere. normally printed on the paper but also in the specs sheets...the measured gap between straight edge and casing edge should be at least the compressed thickness of the gasket plus a tiny bit (info in manual i think). Job is best done with front valance off and radiator (or at least the bottom radiator/oil filter guard) removed. The cover bolts can be either six sided set screws or twelve cornered set screws. Normal twelve cornered,, standard socket or ring spanner will fit them. if the car was ever fitted with the later taller gears it may have a spacer plate and second gasket. Access can be improved slightly by jacking the engine up a bit. you can check the mounts are still stuck together at the same time...
 
I have tried to do this process on an SD1 front cover and found measuring gasket thickness unreliable at best. There is some wear on the cover, but its quite light to my eyes. Access is good as engine is out.
 
You need to find the manufacturers compressed thickness figures for the process to work. Measurements dont work as the gasket is thicker before being compressed when bolted up.
Problem is that the 'too tight' Measurements are hard to take. You could do a test with bearing blue but that might bend the cover on bolt up if too tight. However, if all the parts bar gasket are original and were working and there is only light wear on the cover it would be very unusual for a new factory gasket to add up to 'too tight'. I doubt they go through that whole process on an assembly line they just rely on the parts being within tolerance. the measurement process is really for new gear sets where there is no gaurantee they are in tolerance.

If you assemble everything and tighten the cover down in small steps you can test for tightness as you go if it locks up you'll need to use thicker gasket material... If its free when bolts are up to full torque then its good to go - given the end gap isn't too great - hence need to follow up with a putty test, which is same process with bits of putty on end of gears. it'll compress and you can measure height of compressed putty when end cover removed.
 
Looking into oil pump clearance is now confusing. I seem to recall some complicated checking of clearance of the gears and the cover, but all I can find now is , roughly, gears should not be LESS than .002" proud of the cover face, both in the P6B book and the SD1 book. So, I now propose to check that figure, and tighten the cover and gasket, dry, with some Plastigauge on the cover face so I can check its not binding.
Good plan?
Just spent an hour or so getting the gasket remnants off the cover and body.....not fun at all. Anyway, that enabled me to check gear height, and there is more than .002", maybe .003"+, so all I have to worry about now is finding a gasket that doesnt bind the cover against the gears.
 
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If you dry assemble with your chosen gasket to firstly check for binding, then if gears rotate remove cover and install a strip of plastigauge to check clearance, do not rotate when plastigauge is used as it will give a false reading. I have several sheets of gasket paper in various thicknesses to make gaskets in a situation like this. You can calculate whether you need to go thicker, or thinner.

I would also not bring up oil pressure by cranking the engine, it may take too long. Make an oil pump priming tool from a steel rod and using a cordless drill spin up the pump until you get oil at the rockers.
 
Good morning H
I have always had luck with mine ( 18V )
It is a good indicator as the when the pump 'grabs' the oil, it certainly slows the drill down, then you can start looking for oil at the rockers.
 
I have access to pump turning parts for both P6B and SD1 types. Also have 18v drill with 2 batteries, so that ought to work.
thanks
 
I have access to pump turning parts for both P6B and SD1 types. Also have 18v drill with 2 batteries, so that ought to work.

plastigauge says the cover is close to .003" clear of the gears, so happy with that. Filled with vaseline, cover attached, bolts torqued up at 9 ft/lb except for the one you cant get a socket on - 1/4 drive torque wrench for small stuff. Now struggling to get the box mated up, not having much success.
thanks
 
Yes. I am replacing an LT77 with dodgy synchros with a recently overhauled box. I can get the flanges within ~30mm but cant get the shaft to mate with the clutch plate. I am doing it this way as I am sure I no longer have the strength to do a box swap from underneath - I nearly gave up last time. The weight of the box and difficulty maneuvering it confirms my approach- I may need to seek some assistance....
I will dig out the plate alignment tool and check that it is OK, but I havent disturbed the clutch since separating the old box.
 
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At 30mm away it is likely the splines have entered the clutch disc, probably it is the last bit into the spigot bush that is the hold up.
The Alfa did this to me recently, I had to use a large lever against the chassis cross member to get it to close up, not so easy for you when the lump is out on the floor.
If you take it off again to look set a spline on the clutch disc at 12 o clock, and then same again on the input shaft to be sure.
 
To add to @cobraboy I had the same issue on race Frogeye sprite recently. I ended up using three G clamps to snug up the bell housing to the adaptor plate. Each one a half a turn in order and that aligned things without too much pain.
 
Difficult to align splines on a 23 groove shaft. The plate had moved out of alignment, probably when I separated the old box, so I relaxed the cover, aligned the plate, bolted down the cover. With the engine sitting on a rubber block at the rear of the sump I managed to get the mating faces close. a few jacks of the engine got the faces parallel and eventually it engaged the plate. As I got all the bolts engaged and tightened them I kept checking it was engaged - at one point the flange turned - I had knocked it out of gear! All done up so that's todays progress.
Next question - when I get to try for oil pressure with a drill do I have to have the car on its wheels on the floor, OR will it suck up oil with the rear end in the air?
 
I noticed when I had to re-align the clutch plate that splined hub in the centre would rotate a little - few degrees. Is this a bad sign for the plate, should be replaced? If so, best done before putting it all back in the car?
No rush now, waiting on a rear gearbox mount rubber (CRC454A) from UK, none available down here!
thanks
 
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