Gearbox stripdown help?!?

[ToolsnTrack]

Trying to strip down my Getrag 290. I can only get it apart by about 10mm before it seems to stick. Can still jiggle it but it wont part any further:



Every visible bolt and such has been removed so i have no idea what could be holding it together. The bellhousing is part of the box casing though, and i assume i pull the back of the box off and leave the internals on the bellhousing side?

Also, can anyone identify what this little part is for?



found here:


As i have no idea. Its 5 ball bearings and the cover holds 3 of them in with springs...

[chairchild]

I'd gather a guess at it being the bearings holding it together, with an interferance fit. Maybe warm the whole housing up to help release it? Nothing more than 100 degrees though

[ToolsnTrack]

Hmm, that makes sense i guess. Will try that later tonight and reporet back on my results!!

Thanks for the tip!

[chairchild]

Good luck heating the whole lump to a useable temp though - you'll either end up a hot-to-the-touch housing from waving a blowtorch over it, but not a useable amount of heat, or melted alloy from holding the blowtorch in one spot for too long!

A large blowtorch however, would make the job so much easier ;D

[ToolsnTrack]

Aug 15, 2011 18:27:08 GMT chairchild said:

A large blowtorch however, would make the job so much easier ;D

I'm listening...

[scruff]

I have no experience of this box - however I'd not expect it to need heating just to split the cases, they are usually taper roller bearings so should just lift apart. I'd be looking at the gear slector detent ball barings and springs, see if one of them is jamming.

Other option is put long bolts in the case with a nuts in between the cases then wind the nut out to force them apart. Do it progressively and evenly in several places so you don't overstress the case?

[welshpug]

this any help?

www.google.co.uk/search?q=getrag+290+manual&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&redir_esc=&ei=xz5KTurGKMiAhQfmwPnrBw#sclient=psy&hl=en&rls=com.microsoft:en-gb%3AIE-SearchBox&source=hp&q=getrag+290+exploded+view&aq=f&aqi=&aql=&oq=&pbx=1&bav=on.2,or.r_gc.r_pw.&fp=619a54a25cb5b7a7&biw=1440&bih=719

;D

would imagine you'd need to remove the selector mechanism though my only experience of gearboxes is a PSA MA and BE unit.

[chairchild]

Does look indeed like the selector forks, are held in with *something* inside the bellhousing

[bortaf]

usually the selector forks are held in bu bball bearings and springs of some sort under a bolt head on teh casing or a rod in the same way, MT 75's are like this need the rods removing to release the selector rod from the back half of the casing, never had to heat a box to strip it in me life but i'm not a specifit gearbox man just a jack of all trades TBH

[ToolsnTrack]

Will try and further strip the detent stuff. I did see that exploded diagram before, but ti seems like a toploader box. My version is a remote selector, and there are other parts on the casing that don't match. Will get more pics today...

[danblez]

About 3/4 quarters of the way down the fantastic thread lnkned below explains what the ball bearings are for....

www.r3vlimited.com/board/showthread.php?t=148000&page=4

[chairchild]

Aug 18, 2011 11:38:48 GMT danblez said:

About 3/4 quarters of the way down the fantastic thread lnkned below explains what the ball bearings are for....

www.r3vlimited.com/board/showthread.php?t=148000&page=4

omg... I've just spent the last half hour on the FIRST page of that thread! absolutely immense!!

[danblez]

Aug 19, 2011 0:14:35 GMT chairchild said:

Aug 18, 2011 11:38:48 GMT danblez said:

About 3/4 quarters of the way down the fantastic thread lnkned below explains what the ball bearings are for....

www.r3vlimited.com/board/showthread.php?t=148000&page=4

omg... I've just spent the last half hour on the FIRST page of that thread! absolutely immense!!

It is a fantastic build thread, the guy is off his head and the attention to detail just breathtaking. Wait until you get to the engine rebuild pages....

[DavidB]

That's a pain - I've always had trouble getting gearboxes back on the engine, but not the other way round.