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pajir
Pavel Jiricek

(2 posts)

Registered:
06/04/2009 07:25AM

Main British Car:
LT77 gearbox - can't select 2nd gear when cold
Posted by: pajir
Date: June 04, 2009 08:10AM

Hello, we recently put together a new MGB Roadster V8 conversion.
There is Rover V8 engine and LT77 gearbox.
Nearly everything seems to be fine, but there is problem with 2nd gear.
After a cold start I can't select 2nd gear.
If I drive for a while and the engine and gearbox get warmer, it improves.
The selection of 2nd gear is not excellent when warm, but would say it's acceptable.

Could anybody advise me what could be wrong?

Note: We bought the gearbox as a newly refurbished one and there are
some new parts inside, but of course I don't know the quality of the work.


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: LT77 gearbox - can't select 2nd gear when cold
Posted by: NixVegaGT
Date: June 04, 2009 09:13AM

Does this gearbox suffer from the same intermediate shaft bearing retainer flex that the T5 does? In the T5 that can be a symptom of the preload being gone.

The more likely issue is the sync is worn out. There is a little clutch that times the gears and it's not working when it's cool because of wear. Maybe they missed that one in the rebuild. Or the part was crap. Maybe whoever did the rebuild couldn't get the stack off of that sync and figured it'd be fine. How old is the rebuild?


pajir
Pavel Jiricek

(2 posts)

Registered:
06/04/2009 07:25AM

Main British Car:
Re: LT77 gearbox - can't select 2nd gear when cold
Posted by: pajir
Date: June 04, 2009 09:34AM

I bought the gearbox last year but don't have any idea how long it was in the storage after the rebuild.
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castlesid
Kevin Jackson
Sidcup UK
(361 posts)

Registered:
11/18/2007 10:38AM

Main British Car:
1975 MGB GT Rover V8 4.35L

Re: LT77 gearbox - can't select 2nd gear when cold
Posted by: castlesid
Date: June 05, 2009 04:41AM

Pavel,

Not an unusual problem with the LT77 mine is a bit baulky on the 1st to 2nd change until warmed up, and it has all new synchros and bearings.

Do you know what lubricant was used, if gear oil instead of ATF was used that will make it worse,

Kevin


NixVegaGT
Nicolas Wiederhold
Minneapolis, MN
(659 posts)

Registered:
10/16/2007 05:30AM

Main British Car:
'73 Vega GT 4.9L Rover/Buick Stroker

authors avatar
Re: LT77 gearbox - can't select 2nd gear when cold
Posted by: NixVegaGT
Date: June 05, 2009 11:29AM

WHOA~! Good point, Kevin. I totally gapped on that. Pavel, I'm betting they used gear oil instead of ATF. Swap this out asap if it is. It will result in burning out the syncs. The symptom you are having is definitely something that happens when gear oil is used instead.

Good thinking, Kevin.


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