In a message dated 1/25/99 5:26:17 PM, autox@earthlink.net writes:
<< SNIP
the transmission now likes to sneak out of second gear into neutral
SNIP
THE QUESTION -
1) Why? What is (beginning) to fail? Why for her (and in mild
street driving), and not under more severe conditions? Is this
anything that can be fixed without a full rebuild?>>
We have had the same problem in street use. The most likely cause is a worn
"bulk ring". These are used in the later cars rather than synchronizing
cones. The gear and bulk ring have ribbed surfaces, or surfaces with lots of
very small splines, if you prefer. With use, the tops of the spline start
smoothing off and then will no longer hold. Second gear always seems to go
first followed by third gear. The other culprit seems to be a worn layshaft.
We have no clue as to why. Our gear box came out of a wrecked car which may be
the source of some of our problems. We replaced all bulk rings at about 35K
miles and it was fine until about 50K miles when the problem recurred. The
bulk rings and gears did not appear to be worn and several unproductive
efforts at replacing other parts did not solve the problem. Later we got a
rebuild kit from VB which included a new layshaft, bearings and some other
misc. parts. All of the problems went away after this rebuild. We currently
have about 6K miles on this rebuild.
<< SNIP
2) Just how complicated are these transmissions? I have rebuilt
engines for Sprites, MGB's, 914's, Dodge slant sixes,
318-361-383-426 V-8's, and rebuilt (1960-1970) Dodge three speed
gearboxes. Are these complicated little suckers, or within the
capabilities of someone fairly mechanically inclined (and no
special tools)?
Is there a specific book available for purchase outlining a
step-by-step rebuild?>>
You need to be able to measure end play on the layshaft so that correct
thickness shims can be installed. A dial indicator is most helpful for this.
End caps also need to be shimmed. We would not recommend taking the gear box
apart without a book. Mostly because the English love to use small ball
bearings and springs to index sliding parts. While sliding a couple of pieces
apart three springs and ball bearings will project themselves to the far
corners of your work area and very successfully hide. The surprise is likely
to cause you to drop the parts you were holding, causing them to fall into the
dirt on the floor, and now you have no idea how they were indexed!!
Otherwise it is not that hard to rebuild the gear box. We use the factory
shop manual but the list may know of other books. We will be glad to copy the
gear box section from the shop manual and mail it to you if you would like.
Good Luck
Bob and Annice
1960 Sprite (Mk IV in disguise)
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