At 10:29 PM 7/12/99 +0000, Eric Erickson wrote:
>.... gearbox if, on hard decelleration or accelleration .... just decided
to 'let go' of second gear. That is, it simply spits the gear stick back
into neutral with a rather disturbing THUNK.
>My trusted MG guru people .... will have to start dismantling it at $45
p/h... I was wondering if anyone might offer the suggestion which might
shorten their search ....
Things that make it pop out of gear will require disassembly for repair,
regardless. Parts that affect the syncros and the engagement teeth where
the sliding ring mates with the gear are well hidden on the mainshaft
assembly until it gets taken apart.
I had an MGA popping out of gear, either 2nd or 3rd gear under power or on
overrun, when the thrust washer came loose from the front of the mainshaft
allowing end float of the parts on the shaft. This problem may be a little
more obvious in 2nd gear because there's a little more torque involved
there than with 3rd gear.
If the multitude of small teeth inside of the sliding ring or on the mating
side of the gear get substantially worn, that would cause the symptoms you
describe. This would probably require replacement of both the sliding ring
and the gear.
If you have a loose bolt holding one of the levers or the shifting fork on
one of the selector rods, it is possible that the sliding hub is not
achieving full travel and not completing full engagement of that ring of
small teeth on the side of the gear, which could also cause the same symptoms.
For a good primer of the workings of an MG 4-speed gearbox and things to
look for when it goes awry, reference this URL on the net:
This was written primarily for the MGA gearbox, but much of it is also
common to workings of the MGB gearbox.
1958 MGA with an attitude