P6B S Project Car

I can't comment on the gearbox output flange and the diff extension flange being off centre, because I haven't been underneath my car for ages! ISTR having noticed they were not exactly in the middle of the car, but I might have imagined that. All I can say is that my drivetrain is fairly noisy, and I think what I'm hearing is the UJs compensating for the offset! I think the noises were being masked by all the cacophony from my front suspension, and having fixed that I can now hear the drivetrain noises more than before. Or maybe it's just things wearing out that makes it get louder!
As regards trimming those vertical ribs, jp, wouldn't that make the mounts themselves weaker and more likely to deform? I'd rather have tight gaps and not slim down those ribs if possible! I wonder how much the gearbox actually moves at the rubber bushings... ?
 
another view for you JP of the rear of my 4 speed on the car. It shows the spacer pieces on the gearbox rear mounts.

rear of gearbox.jpg
 
That shows the gearbox is closer to nearside of tunnel than offside. here is the cast iron thing, clearly offset the same way - the blind face is the rear..
0EFHAX1.jpg

I make the centre of this part close to 0.5" off centre, towards the near side. it looks like more, but thats what the ruler says.
 
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Re weakening of thebox mount support plates, I think it would be easy to reinforce the area with some short bits of steel angle bolted to the tunnel sides and supporting the mount, even after the box is in place.
 
Moving on a bit. Bought a tranny jack recently ...arrived with one tilt adjusting knob busted. Took a week to get it fixed. Dragged the box underneath - bit of a struggle, had to tip it over to get it under with gear lever fitted. Then had to slowly, bit by bit get it high enough to get on the jack (min height 200mm!). Still fighting to get it high enough to mate to the engine.....gear lever problem, remove it; need to cut some of the offside old mounts back. The boss (offside) where the remote bolts to the alloy is hitting the old rear mount plate, and the reverse gate stuff is hitting the nearside tunnel edge.
The offside head is ~1"above the reserve tap outlet - is that low enough to be able to get the box fitted?
 
Well,,,,, Lowered the engine a touch, cut some more of the offside old mounts off, trimmed a tiny bit off the bellhousing, and its in place, finally. Not out of the woods through. When I could feel the input shaft in the clutch plate splines I started a couple of long 3/8 unc bolts, jacked the box rear up,and started tightening. Soon found the output flange very hard to turn (in neutral), then the crank hard to turn (via the alternator nut). Slackened off the bolts and everything turns again. will try to get a consistent gap block->bellhousing and then tighten slowly....
 
Not really -some was done on the fly, in extremis so to speak. Look up the Penguin motors youtube on P6B LT77, it shows cutting a piece off the part that covers the starter motor, and sanding the ridge down. I cut an extra small wedge off towards the part that the bolt goes through.
My real question is does the tightening up of things occur when the bellhousing is not parallel to the block????Cab there be anything stopping the box pulling properly?

PS checked SD1 book -spigot bush only goes into crank flush, which is what I did,so I doubt the bush is a problem.....Curiously it says to ream bush to 0.750", but the LT77 pinion is 0.500".
 
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After stewing in paranoia all night on what could be causing the problem, back into it today. Loosened off most bolts to ensure I wasnt loading the bellhousing in any direction (some bolts longer than std to ensure it couldnt fall off), check faces parallel, wriggle the box as much as I can manage in all planes, nothing. Try tightening again. As soon as I put any tension on things the output flange would start binding. Re-loosened bolts, tried a different tightening sequence.....Ding! Pinion slid into the bush! Now everything tightens smoothly, feels fine. What a relief. If I ever have to do this again I think I will take a rose bit to the mouth of the bush to help get the pinion find the hole! Now to tackle the 'easier' stuff, like the rear mount etc. So far only 3 bandaids last 2 days.
Here is what I cut off the starter cover...triangle at the top made life a lot easier in the lifting process, after doing what penguin suggest.
5N5SQJV.jpg
 
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Got the gear lever back in, with modified cover plate . Bloodied a knuckle getting the fan nuts back in place - export viscous type. Tidied up all the stray bolts and tools, ready to start on lifting to correct height and work out a rear mount....
 
Connected the reverse light switch. Now looking at the angles of the flanges.....using a digital indicator from building RC model planes. Jacked the box pretty much as high as I can, given the tunnel width - apparently I didnt widen it enough! Also see below - angle of the throttle countershaft - After I fitted a new rear mount on the 4 speed box I believe the shaft was close to horizontal. Now it seems to be angled upwards, as though the engine is higher than it was. The flange centre is still some way below where the old one was.
And....gearbox flange shows 93d vs 87d at the diff, relative to the garage floor. Lowering the gearbox rear decreases the indicated angle. All the diff mounting rubbers are new. Fan is close to parallel with the rad core.
ei6ahVH.jpg


Comments please!
 
More info. With the gearbox flange showing 94d, (ie 4d down). There is very limited room for box to go upwards as the pic below shows. the nearside rocker cover shows 3.1d, the throttle counter shaft 4.1d (so shaft is pointing uphill). The diff nose mount has the distance piece listed for suffix B diffs. Its flange is showing 87d, which means its also pointing downwards?maybe? Moving the gauge as though lowering the diff nose the angle displayed goes UP...?
1EpPXrC.jpg

I can get all the gears without the lever getting close to the edges of the tunnel hole.
Have I got this all confused? Box flange at 94d, box is POINTING UPWARDS at 4d- correct? Diff flange at 87d - is it pointing UPWARDS at 3d?
I zeroed the gauge on the floor, for the box flange, rotated it CW and placed it vertically on the flange, offside. For the diff, gauge is rotated CCW and placed on the flange also on offside.
???
Non-problem - was not reading the angle thing correctly, confused by the faces of the flanges being checked faced each other. They are within 1d of parallel.
Next?
 
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Next, drink a cold beer. Pat yourself on the back. Resist the temptation to quaff further cold beers. Bolt everything back together and go for a drive. If nothing explodes, binds, grinds, rumbles or ejects itself from the vehicle, press on somewhat harder. This is called a 'shakedown test'. You must avoid patrolmen in order to avoid being shaken down for money for having explored the upper limits of your vehicles speed range. After a really long drive your glee will eventually subside sufficiently for you to return home, park the old girl up and write up your adventures on here.
 
There is some adjustment for the throttle shaft by moving the bracket at the firewall end. The plastic universal joints do wear out too and that one looks somewhat worn. its the internal slots that wear away, making the thing sloppy. Eventually you will start breaking the split pins, then you'll be driving home at idle...New ones are available for not much and they do give a nicer throttle feel.
 
Thanks Mike, I would never have thought of replacing that coupling! apart from the rear mount (many thoughts already), speedo cable is only issue i cant see a fix for yet. Cant see it reaching without some work, angle looks bad.
 
Seeing an angle of 93d on the gearbox flange, and 87d at the diff is what confused me. Then I noticed the little pointers on the gauge were pointing in opposite directions, so the numbers were opposites, ie each a 180 complement of the other.
 
I have now trial fitted a couple of mounting options using the round bobbins. Using them in the angled holes and an SD1 bracket , the bracket ends dont meet the body metal very well, and using the bobbins in the two vertical holes isnt much better. modifying the bracket is a problem for me as while I can cut them, welding is beyond me, and not easy to get done.
Using the TR7 rear mount looks more promising. It would need a spacer (~1/4") on top to keep it clear of the next flat part of the rear casing. Assume it would be mounted on a flat steel plate, under the mount flange. On the left of the pic there is some almost flat surface it could bolt to, and on the right it could, with a spacer bolt to the old rear mounting plate. This is a similar approach to that visible in the penguin video.
vRsZFoE.jpg

Comments please?
 
Let me get you a picture of my TR7 mount. I have started to modify it although my gearbox hasn't been near the car yet.
 
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