Ron:
Lots of little bits!
I have had the same condition with a couple of gearboxes - the deposit of
synchro ring material onto the gear cone. You don't want to do anything to
damage even slightly the hardened surface of the cone, if you do, the cone
will eat the new syncro ring very quickly. I am leery of wire brushing the
surface.
What I have done - use nothing coarser than crocus cloth, peferably with the
piece spinning in a lathe ( I borrowed the use of a brake lathe) - hold the
cloth fairly gently on the spinning cone until the surface is clean. I
normally would not have worried about this, but I was upgrading to the
sintered bronze rings from the original brass, and wasn't sure if the
deposits would adversely affect the new material. I did all 3 cones,
including 4th, which is integral with the input shaft. (which is where I
had the most material deposited for some reason).
It is normal in a Healey gearbox to have more wear on the 2nd gear sychro
ring - it's smaller than 3 and 4, and of course, it gets much more use. One
simply has to smile at the logic of that engineering!
Another matter to consider: I have heard that some of the current synchro
rings are 'just a little off', and that some people have had problems with
the rings not working properly. Since it's so much fun re and re-ing a
Healey gearbox/OD unit, it may be worth having a knowledgeable machinist or
gearbox specialist (who has a feel for the older style gearboxes) hand lap
the rings to the cones to insure that the thing works right the first time.
At the very least, get some advice on this from a pro.
Let us know how you make out.
Earl Kagna
Victoria, B.C.
BT7 tri-carb
BJ8
----- Original Message -----
From: "Ron Fine Esq." <ronfineesq@earthlink.net>
To: <Healeys@autox.team.net>
Sent: Thursday, May 20, 2004 8:47 PM
Subject: Synchro Ring replacement
Well, I have successfully completed the disassembly of my transmission. All
the gears look good except for one chipped tooth on the large end gear of
the
Laygear. I don't see any other damage to the other gears and the
transmission
was running well before the disassembly so I'm going to keep the existing
laygear but replace the shaft and bearings. From all appearances the tooth
has been chipped for a long time without a problem. The third and forth
gear
selector shaft was badly bent and it will be replaced. I am also replacing
all the small detent springs and roller bearings. The Synchros were worn,
one
more then the others and I have ordered new ones (the expensive ones). Now
for my question: The old synchros seem to have left some of themselves on
the
mating surface of the gears. There is a thin layer of gold colored metal on
the cone shaped part of the gear that the synchros run against. Is this
transfer normal? Should I attempt to remove it before installing the new
synchros? Wire brushing should do the job or should I leave it in place?
Any
help is always appreciated.
Thanks,
Ron
61BN7
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