gearbox removal?

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kennatt
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Re: gearbox removal?

Post by kennatt »

i(t has a release bearing noise too! ie rumbles when clutch pedal is released but quiet when pressed altho i didnt think
the carbon thrust bearing would do that?mark t4 )

It dosn't,the noise will be the first motion shaft bearing.
Phil-1954
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Gearbox Renewal

Post by Phil-1954 »

All,
I have a re-con box, and someone, a retired mechanic, is going to change the gearbox & clutch for me, following loss of syncro on 2nd gear, and with a couple of long journeys coming up, I'm playing safe.
It is a 1967 1098cc model, but currently I'm unable to get under and check through the procedure myself. My neighbour (who's not the one doing the job) is adamant, having done several himself, that you need to remove the box by taking the floor out or pull out engine & box together conventionally, as the cross-member of the gearbox does not remove from the body.
Here on this forum though, it generally seems the gearbox cross-member does unbolt on a ribbed 1098, allowing the floor to stay in situ. So for a 1967 1098cc model, is removal from under the car feasible (he has a lift) and is the post from the archives shown below still accurate to my model?
simmitc wrote: Fri Aug 08, 2014 6:51 pm I think that 45 minutes is optimistic for the average owner. Yes, in a workshop with all tools to hand, four post lift, and everything working, and an assistant to hand, it might be achievable. For the average owner working on the ground with minimal tools it's going to be a lot longer:
Disconnect battery.
Drain gearbox oil.
Jack up rear of car, place on stands, remove prop shaft - at least one bolt really tight.
Lower rear of car.
Remove gear stick gaiter and stick.
Depending on preferences, remove gearbox cover and therefore seats.
Raise front of car and place on stands (optionally, do this first and then also raise rear of car, but it depends on what stands one has available).
Disconnect engine steady bar to allow engine to tip downwards.
Remove starter motor.
Disconnect clutch linkage.
Support box and engine
Remove gearbox cross-member - at least one bolt probably seized, so definitely need to remove gearbox cover to get to cage nuts. worst case, remove master cylinder to gain access for repair.
Remove all bolts holding bell housing to engine back plate - top two may be difficult to reach. Fine if you have an open ended ratchet, otherwise may require many small movements of spanner.
Lower engine and box.
Slide box back, taking care to not break the top of the bell housing by catching it on the steering rack, and also to not hang the box on the input shaft/clutch. Great care needed, the box is heavy.
Fit new box - a reversal of the above.

OK, that's not precise, but gives an idea of what is needed, and what might happen. I suggest that for the average owner with DIY facilities, you should allow a day and be pleased when you manage 4 hours. I believe that it is important to set the correct expectations, and most owners won't have years of experience to know the short cuts and have the correct tools to hand.
Regards

Phil T
http://www.hvtesla.com
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philthehill
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Re: gearbox removal?

Post by philthehill »

The above method is basically correct - when you remove the gearbox you do have to twist the gearbox as you lower so as to allow the bell housing to clear the rack.

Even if you drain the gearbox expect some oil to come out of the tail housing when the gearbox is lowered. That is why I suggested fitting the front part of an old propshaft into the tail shaft to ensure that you do not get covered in oil.

Personally I would make sure that the gearbox cross member bolts are free before doing anything. There are two either side going into the underside of the chassis legs and two either side going through the floor. Hopefully the mechanic who did the previous gearbox removal/refit smeared the cross member bolts in copper grease so as to make it easier for the next person doing the job.

If any of the bolts mentioned above are seized you need to re-appraise the job and if not sure what to do next come back on here for further advice.

Phil

simmitc
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Re: gearbox removal?

Post by simmitc »

Yes, the cross member is removable on your car (unless someone has welded it in place) and as Phil writes, 4 bolts underneath the car facing upwards. These are hex head. Inside the car are lots of cross head brass screws (some new replacements are slotted) holding down the gearbox cover panel. Either side of the cover are two rows of screws; and in the inner rows, two of those scvrews are longer than the rest and go through the floor into the cross member.
Phil-1954
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Re: gearbox removal?

Post by Phil-1954 »

THanks both of you
Regards

Phil T
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newagetraveller
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Re: gearbox removal?

Post by newagetraveller »

I have a pit in my garage and I could usually do it in an afternoon.
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