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Synchromesh Gone - Options?

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DenverMGB

DenverMGB

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The synchromesh has finally given-up on 2nd and 3rd gears in my '79 B. I guess I can rebuild, replace or install a 5-speed conversion kit - in order of increasing cost/decreasing work I think...

I'm leaning towards the 5-speed conversion as I have help from a neighbour with an engine stand and massive tool-set. Does anyone have any experience of this conversion and the after-effects (drivability, ease of maintenance, etc.)?

Supplimental question ;-) -- what else should I be thinking of replacing when I take the engine & geabox out?

Thanks all!
 
Clutch disc, pressure plate, T/O bearing, pilot bushing, maybe even the rear seal and retaining piece. Of course alot of these depends on the transmission choice you make. When you pull the engine, it also a good time to pull the pan, and take a look at the bearings, of course other exterior related engine items, like motor mounts, oil filter housing o-ring, any rubber piece that age attacks.
 
Hap..

OMG... The 'Just as well do this while I am at it..' syndrome strikes again... :smirk:
 
ronzet said:
OMG... The 'Just as well do this while I am at it..' syndrome strikes again...
Click to expand...

Exactly what I wanted to avoid by posting the question!

I think I'll have to dismantle then inspect and renew anything that looks worn/perished/broken. That'll lengthen the process by a week or so whilst parts arrive. Oh well.


Does no one have any opinions on the main question - to repair, replace or 'upgrade' the gearbox?
 
DenverMG,

I might suggest that finding a rebuild 4 speed/OD unit might be the best of both worlds... Plug right in (basically), only wiring and a drive shaft to modify/change... Gives you good highway performance in OD and MAY cost you a lot less....
 
I'd be for rebuilding it. The later four synchro MGB box was a fairly stout unit. Done once right it should last a long time.
 
Dr. E, I am looking at the same issue with my B, 3rd gear synchros are weak, what is typically replaced in a rebuild, synchros and seals and anything obviously worn I guess?? Anything else?

Thanks, Greg
 
Layshaft and bearings, input and output shaft bearings 'n seals too. You only wanna do this job once a decade. :wink:
 
DrEntropy said:
Layshaft and bearings, input and output shaft bearings 'n seals too. You only wanna do this job once a decade. :wink:
Click to expand...

Decade? With the mileage most owners put on their cars, a rebuilt all synch should last them as long as they own the car (unless they are ham-fisted gear grinders, in which case they'd deserve their fate)
 
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