28 replies to this topic

[Guess-Works.com]

Just looked at the photo, and if that cover was on the A+ gearbox in the next photo, you may as well bin it anyway as it's not the correct cover for the gearbox case... the one in the photo is off an A series box.

 

And, don't buy or put any random diff cover on the case as the case and the cover are a matched pair and machined as one unit...  putting the wrong cover on is like putting the wrong main cap on an engine or big end cap on a conrod...

[A-Cell]

+1 to that. Diff casing is machined as part of transmission casing.

Tig welding best if you have facility otherwise bonding. Good luck.

[Barman]

I had the same problem with mine...

 

I understand that the diff/gearbox housings are a matched pair so you cannot replace one without the other.

 

I was going to do a gearbox re-build anyway so I bough a new (well, new to me) gearbox and diff housing from Guessworks for a very reasonable price (along with a gearbox re-build kit)...

 

[EDIT] Don't know what happened there - I thought I made this comment on page 1!

Edited by Barman, 20 May 2013 - 06:28 AM.

[grahama]

consider me told lol,  didn't know that !!

[Chappb]

Just looked at the photo, and if that cover was on the A+ gearbox in the next photo, you may as well bin it anyway as it's not the correct cover for the gearbox case... the one in the photo is off an A series box.

 

And, don't buy or put any random diff cover on the case as the case and the cover are a matched pair and machined as one unit...  putting the wrong cover on is like putting the wrong main cap on an engine or big end cap on a conrod...

yes it is off that gearbox in the next photo, hmmm... is there a distinct difference between a+ and pre a+ diff housings?? when i got the engine/box the diff and output covers were on, nothing seemed out of place

Edited by Chappb, 19 May 2013 - 10:00 PM.

[Chappb]

Without trying to be funny about this Guessworks, i've just gone on one of your gearbox rebuild videos 'Part 6- Final assembly' and i took this screenshot which says early A+ covers had the '22G' prefix to their part number, well mine has....i'm guessing this means it is a A+ diff cover after all? 

 

Picture of '22G' part number on my diff cover

http://www.flickr.co.../in/photostream

Attached Files

•  Screen Shot 2013-05-19 at 23.22.11.png   221.86K   6 downloads

Edited by Chappb, 19 May 2013 - 10:40 PM.

[Guess-Works.com]

Yes, but your gearbox has a single groove gearset, which means unless the gearset has been changed, the gearbox is a later A+ gearbox which should have a DAM* prefixed diff cover.

 

Quick way to check is the number of bolts which hold the main bearing retainer in, but the shape of the casting around the idler gear gives the game away.

Edited by Guess-Works.com, 20 May 2013 - 06:37 AM.

[Chappb]

Mine has 3 bolts, which i believe was the later type? here's a piccy

 

http://www.flickr.co.../in/photostream

[Guess-Works.com]

Later gearboxes should not have a 22G* cover, but a DAM* cover, this is also important when building the gearbox together... the section you highlighted in one of my videos concerns the use of gaskets or RTV between the diff cover and transmission case. Those using the 22G* cover are likely to need gaskets, where as the later DAM* covers are more likely to use RTV...

 

This is why, a few frames later, in the video I suggest that the case is measured.

[Chappb]

Hmm, right then i'll have a measure later on. What are the risks in using that cover with that box?

[Dan]

  If it's not the original cover, and even more so if you don't know whether or not to use a gasket with it, there is very little chance it will support the bearings properly.  They might be close enough, they might be too loose or too tight.

[Chappb]

Is it just going to be better to get another casing, you have any spare ones guessworks?

[Guess-Works.com]

Replacement cases on the shelf. A+ 3 bolt - £50 + vat + carriage.

 

There's a multiple of issues which can be the result of an incorrectly fitting diff cover...

 

firstly, the one of oil leaks, if the cover does not fit properly, then there's a strong possibility that it leak like a sieve.

 

Even if you do manage to avoid the leaks by either copious amounts of silicon or blind luck, then the next issue may be with pinching up or even loose bearings.

 

And the most important, the mainshaft and differential axes need to be parallel, if they are not then there is going to be a misalignment between the crownwheel and the pinion. This will result in a noisy gearbox, and one which will be prone to premature wear and possibly critical failure. 

[Chappb]

Replacement cases on the shelf. A+ 3 bolt - £50 + vat + carriage.
 
There's a multiple of issues which can be the result of an incorrectly fitting diff cover...
 
firstly, the one of oil leaks, if the cover does not fit properly, then there's a strong possibility that it leak like a sieve.
 
Even if you do manage to avoid the leaks by either copious amounts of silicon or blind luck, then the next issue may be with pinching up or even loose bearings.
 
And the most important, the mainshaft and differential axes need to be parallel, if they are not then there is going to be a misalignment between the crownwheel and the pinion. This will result in a noisy gearbox, and one which will be prone to premature wear and possibly critical failure. 

So after vat and carriage it's going to be around £75? I'll PM you at the end of the week and try and sort something if that's ok. Thanks.