Ken:
As previously posted by list members, it is probably the clutch
system.
Synchromesh cones act as brakes on the input shaft, matching the
input shaft rotation with that of the selected main shaft gear. At a rest,
when the clutch is engaged the synchro cone will brake the input shaft to a
stop, so that the stationary 1st gear can dog into the input shaft gear.
Slight input shaft drive, due to the clutch not fully disengaging can be
retarded by a good condition synchro cone.
On the later transmission, reverse is the only gear without a
synchromesh cone. This is the one gear that cannot handle any input shaft
rotation. Any clutch disengagement problem will show as an inability to
engage reverse.
Possible problems:
Hydraulic.
Air in the line, or leakage at the cylinder.
Mechanical.
Overly worn clutch pedal, and/or push rod clevis pin hole.
Worn out, or destroyed throw out bearing surface.
Foreign material stuck in the disc surface.
There could also be a combination of the above. Repairing a worn
out pedal or pushrod could give you a bit more life if there is a worn down
throw out bearing. If the hydraulics are working correctly (no leakage).
Check the pedal, master pushrod and slave pushrods. Repair any wear.
(replace, or weld and redrill) It is possible, but not recomended to
lengthen the slave pushrod slightly. This may give you a few more miles to
enjoy the car before pulling the engine to do a clutch job. The
disengagement problem will put extra load and wear on the synchro cones, so
keep this in mind when scheduling the repairs.
Hope this helps
Kelvin.
-----Original Message-----
From: Ken Waringa [mailto:kwaringa@dynsys.com]
Sent: Thursday, March 09, 2000 6:08 AM
To: MG
Subject: No reverse
We got the newly purchased 79 MGB going last night. It shifts and runs in
first gear great, no grinding and very smooth. The problem is that is won't
go into reverse, just grinds. I haven't done any troubleshooting at all
yet. I wondered if anyone had any idea what to look for. Hopefully
something minor, but I have my doubts.
Thanks,
Ken Waringa
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