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Re: Gearbox woes

Posted: Wed Mar 13, 2019 11:36 pm
by ndevans
I've started to get the gearbox apart to transfer the innards to the spare bellhousing. So far, I've got the clutch release fork off, and the side cover off, but not started dismantling the gears yet.
There's quite a bit of play on the input shaft from the engine-is this normal? If not, what needs replacing?

Cheers N

Re: Gearbox woes

Posted: Thu Mar 14, 2019 9:44 am
by philthehill
A small amount of play on the first motion shaft is normal as the rear of the first motion shaft is carried in a single row ball bearing. When the nose of the first motion shaft is inserted into the crankshaft tail bearing all the play should be eliminated.

Re: Gearbox woes

Posted: Mon Mar 18, 2019 3:46 pm
by ndevans
Quick question.

One of the locking plungers in my spare bellhousing has rusted in place. I've soaked it in WD40, and will have a go at removing tonight. If that doesn't work, how do I get it out? Can I risk using heat on an aluminium bellhousing?

Cheers N

Re: Gearbox woes

Posted: Mon Mar 18, 2019 5:09 pm
by myoldjalopy
Try skeeting the plunger with 'Plusgas' before thinking about heating it up - Plusgas is much better than WD40 for releasing corroded parts.....

Re: Gearbox woes

Posted: Mon Mar 18, 2019 11:12 pm
by ndevans
A bit of tapping with a slim punch, from both sides of the lock plunger, and on the end, finally worked it free. Took about 1 ½hrs, but I got there. I'd have tried plusgas of that hadn't worked.

Does anyone know what this plastic plug in the upper surface of the bellhousing is for? There's nothing similar on the bellhousing that came out of the car.
IMG_20190318_225345.jpg
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Re: Gearbox woes

Posted: Tue Mar 19, 2019 7:13 am
by philthehill
It is a bodge for some reason or another and should not be there.

Re: Gearbox woes

Posted: Tue Mar 19, 2019 2:24 pm
by Declan_Burns
It looks like some sort of a port to act as a remote oil filler and yes it is a bodge.
Regards
Declan

Re: Gearbox woes

Posted: Tue Mar 19, 2019 2:52 pm
by ndevans
Hmmm thanks all

How best to plug it up? A short bolt with a copper or fibre washer?
I have no idea whether it leaks, and I don't want to find out by peeing oil all over the motorway!

Cheers N

Re: Gearbox woes

Posted: Tue Mar 19, 2019 3:21 pm
by philthehill
Is the insert threaded - if it is just use a suitable bolt and of appropriate length to plug the hole.
If it is not - remove the insert and tap the hole and again use a suitable bolt of appropriate length.
You could even tap the insert and plug as above provided the insert is secure in the gearbox casing.

What ever you do - do it before assembling the gearbox so as any crud generated in plugging the hole can be easily removed.

Re: Gearbox woes

Posted: Tue Mar 19, 2019 4:20 pm
by ndevans
I'm guessing it's not threaded. It seems to be a piece of plastic held in place by what looks like some sort of sealer.
Would a bolt and nut be ok, with suitable washers, or does the hole need to be threaded?

Cheers N

Re: Gearbox woes

Posted: Tue Mar 19, 2019 4:36 pm
by philthehill
If you can fit a nut and bolt through the plastic insert so much the better but make sure that you have adequate clearance between the head of the bolt (on the inside of the box) and the gearbox internals - fit a self locking nut to make sure that it cannot come apart.

Re: Gearbox woes

Posted: Tue Mar 19, 2019 6:41 pm
by les
No doubt the suggestions mentioned will sort things out but I’d have to remove the thing completely and see what I was left with. It looks too much of a mess to leave, in my opinion of course! :D

Re: Gearbox woes

Posted: Tue Mar 19, 2019 11:21 pm
by biomed32uk
I would be the same as Les, it would have to come out and then I would get someone to TIG weld it up. Thats certainly not been done in an engineering manner, whatever it was trying to do.

Re: Gearbox woes

Posted: Wed Mar 20, 2019 8:18 am
by GavinL
if you are feeling brave you could try a low temperature 'welding' system like https://www.alumiweld.com/ . I've used this in the past to weld a cooling fin back onto a C15 cylinder head, and recently to repair the holes in a thermostat housing. Alternatively what about a quality aluminium putty such as Devcon https://www.cromwell.co.uk/shop/materia ... EV7112030X - i think you can get smaller quantities more cheaply.

Re: Gearbox woes

Posted: Thu Mar 21, 2019 8:01 am
by ndevans
Thanks, I might try alumiweld.

Here is the plastic insert:-
IMG_20190319_230607~2.jpg
IMG_20190319_230607~2.jpg (725.88 KiB) Viewed 2505 times
The hole it fits in is slightly over 9mm, and the insert is not a tight fit, it was held in place by sealer.

I have managed to get a 7mm screw cut to length inside the insert, and a nut behind on the inside. I will take it off, put some loctite on the thread, and some blue sealer around it, and it should be fine.

Cheers N

Re: Gearbox woes

Posted: Thu Mar 21, 2019 9:16 am
by StillGotMy1stCar
That looks like the remains of a rear axle breather, most likely fitted as an attempt to stop oil leaks?
Regards John.

Re: Gearbox woes

Posted: Thu Mar 21, 2019 10:14 am
by ndevans
StillGotMy1stCar wrote: Thu Mar 21, 2019 9:16 am That looks like the remains of a rear axle breather, most likely fitted as an attempt to stop oil leaks?
Regards John.
Possibly, but it was plugged up with sealant. I can't imagine it would have stopped oil leaks, I don't think the gearbox is pressurised anyway. And surely it'll leak oil through there? It's not quite on the top, but I don't like the idea of it being open. I don't want to wee oil along the motorway!

Cheers N

Re: Gearbox woes

Posted: Thu Mar 21, 2019 11:38 am
by les
Are you saying you’re putting the insert back?

Re: Gearbox woes

Posted: Thu Mar 21, 2019 11:48 am
by ndevans
Yes, with an M7 screw threaded through it, and a nut on the inside of the box. I will loctite the nut, and use blue hylomar to seal it. I think that should keep it oil tight.
Cheers N

Re: Gearbox woes

Posted: Thu Mar 21, 2019 10:49 pm
by les
You may well be right, however I’d have thrown that insert into the nearest bin! :D