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Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 12:38 pm
by guru_1071
it wont be ok, if the gear is tight now it will soon heat up and either grab the crank or chew the back top hat bush up.
you will probably have problems releasing the clutch.
if the clerance on the idler is ok, try thinning the brass spacer ring down more on the crank
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 12:52 pm
by wil_h
It surely can't be related to the primary gear, you coyuld tighten the end cover up as much as you like it will never stop it moving. It must be the idler of the bottom one (whos name eludes me). My guess is that the gasket is too thin and the idler shims too thick.
Have you measured the float on the idler? only way to do it is take the engine off the box and bolt the end cover on. I end up changing thrust washers and gasket types until it's within spec.
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 1:03 pm
by guru_1071
i assumed you had tried the clutch as well, sorry!
i have seen gold seal boxes in the past that have had the idler gear hole repaired with a top hat bush, then had the whole face skimmed, this closes the gap up between the box face and the endcover and causes all sorts of clerance problems!
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 2:37 pm
by GraemeC
I have had a similar issue in the past where all I have replaced is the gasket following a strip down and the idler gear nipped up tight. The casings, gear, thrust washers etc were all the ones removed, only the gasket was new. If I remember rightly it gave about 6 thou preload!!!!
I had a selection of around 8 different gaskets and although there were differences none were anywhere near what I needed. I came to the conclusion that in the dim and distant past end casing gaskets were available that were much thicker than what you can get now. I changed the end casing in the end and then chose thrust washers and gaskets to suit.
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 2:48 pm
by Vegard
I understand if the idler gets tight, not the primary...
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 6:15 pm
by Matty
The only real way to know what the clearance is, is to unbolt the block from the box and bolt the transfer housing up to the box and check the clearance with feeler gauges.
If you want to take a chance you could mic up the old gasket and the old thrusts, then mic up the new gasket (compressed) and work it out.
If it were me, I'd rather have a skim taken off the thrusts than use 2 gaskets.

Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 6:29 pm
by almondgreen
The only real way to know what the clearance is, is to unbolt the block from the box and bolt the transfer housing up to the box and check the clearance with feeler gauges.
If you want to take a chance you could mic up the old gasket and the old thrusts, then mic up the new gasket (compressed) and work it out.
If it were me, I'd rather have a skim taken off the thrusts than use 2 gaskets.
If my english would be better, I would have written this.
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 10:51 pm
by Ronnie
How thick ar the gaskets? [Imperial or SI (metric)]
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 21, 2010 11:51 pm
by JanWulf
wil_h wrote:Have you measured the float on the idler? only way to do it is take the engine off the box and bolt the end cover on. I end up changing thrust washers and gasket types until it's within spec.
There is another way

It's described in the official BL manual (late 70s edition)

Similar to the method utilised to check main bearing's clearances...
anyway; if the idler tightens up, there's NO clearance, but a preload; which is wrong no matter what
@brook shaw: what colour gasket have you got? There are some black/grey-ish ones around which are very thin. MinSpares sell the original thickness gaskets which are indeed much thicker. But I would still not rely on it without measuring the ACTUALL clearance. It's an A-Serie's Achilles' heel after all
I'll measure some MS gaskets up and post the results...
Cheers,
Jan
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 12:52 am
by Steve A
I had a similar problem a while back but it wasn't that bad, you could turn it by hand (the primary gear) but too much resistance and very stiff, i changed the gasket and carefully tightened the bolts up on the transfer housing and kept turning the primary gear to check it, there was only slight resistance when they were nipped up and all was fine, amazing the difference a gasket can make. Regards Steve
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 7:16 am
by austinisuseless
Aren't various thicknesses of thrust washers for idler and primary gears still available? There used to be various ones on BL parts lists to use after checking which ones are needed.
Haven't put together a transverse engine and box for a long while, but check the idler clearance by putting the flywheel housing on the gearbox only first, torqued to the correct amount, using a brand new gasket, and use a feeler gauge slipped down the side to check that the idler float is set up properly using the correct thickness thrust washers. Might take a few goes to get it right. And then bin that gasket, and use an identical same make/same thickness new gasket for after when the engine is fitted on the gearbox. The correct thickness thrust washer being used on the primary gear also to give the correct end float on that as well. You'll need a micrometer as well as a set of decent feeler gauges to measure and check everything. As you're tightening the flywheel housing on, keep double checking by turning the primary gear that it feels the same until all torqued up, and that nothing is tightening up, making sure the gearbox is always in neutral, obviously.
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 8:33 am
by mk1
I tend to agree with the general thrust of what has been said. Its unlikely that its the primary gear that is binding the front runner has got to be the idler gear. Without a cheap set of digital vernier calipers its very hard to ascertain whether what you are doing is right or wrong;
http://cgi.ebay.co.uk/LCD-DIGITAL-CALIP ... 45f62ebb3e
These really are a piece of cake to use, and with one you can fit the idler gear with no thrust washers, bolt it all together & measure the end float from the gearbox side. This will tell you exactly how much clearance is needed. It is then a case of selecting idler gear thrust washers to suit. At a push, if the gasket is really megger thin you may have to get one of the washers surface ground to thickness.
Alternatively, buy a "genuine" gasket set from a reputable supplier & this will probably solve the problem much easier.
I don't know how thick the side cover gasket that you have there is, but a "normal" one should be around 1.5mm thick.
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 4:43 pm
by Vegard
brook shaw wrote:think there is a big issue with the trasmission gaskets sold at the mo
just delved into my parts bins,and found another side cover gasket,,it seems 3 times thicker than the one supplied by the major parts supplier,,
soooo if buying off ebay or mail order,-u never know wot ur gonna get,,it seems#
may try this thicker gasket,,
how many others have had the gasket causing tight clearance probs??
No, never it's the other way around. The cheap gaskets make idler clearance WAY too big. I always buy the Rover gaskets, and it's VERY important to get all the old junk of the casings.
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 6:15 pm
by Steve A
It was pinching up the idler gear on mine but what i meant was by turning the primary gear by hand i could feel the resistance.
When i first put mine back together i wasn't aware of this problem and fitted a 'thin' gasket and tightened up the tranfer casing bolts by 'feel' and maybe overtight. I drove the car and it was o.k. until warm, then came difficulty changing gear. After stripping the flywheel off in the car and a bit of investigation we found the problem. We made the decision to replace the gasket but couldn't say 100% that it was a thicker gasket but i remember using gasket sealer both sides of it lol. We then replaced the casing being very careful tightening the casing bolts and checking the resistance on the transfer gears as we went and it seemed fine this time. I think i may have had more luck than judgement as it was fine after this and my son put a good 6000 miles on it before it was sold.
I think that minispares sell about 3 different thickness of idler washers if need be.
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 7:06 pm
by austinisuseless
How warm was it?
Steve A, well done, get to bed now, let me sing you a song to get you away.
http://www.youtube.com/watch?v=CaC2K34SLhc
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 7:32 pm
by austinisuseless
Not a gasket issue, just simple we do not have parts quality anymore, since Thatcher in the 1980s decided for all of us we didn't need it, in her infinite whatevers.
song,
http://www.youtube.com/watch?v=SSR6ZzjDZ94
Re: tightening of primary gear when fitting end cover-
Posted: Wed Dec 22, 2010 10:19 pm
by Steve A
Not sure how to take that Austinisuseless? was it an attempt at sarcasm?
Re: tightening of primary gear when fitting end cover-
Posted: Tue Dec 28, 2010 3:00 am
by Steve A
Great news.