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Re: Trans apart, a few questions (longish)

To: Kyle Hagemann <kwhcpa@addler.net>,
Subject: Re: Trans apart, a few questions (longish)
From: jhatfield@cavemen.net (William Hatfield)
Date: Fri, 26 May 2000 12:25:54 -0600
Hello:    Any time a tranny breaks pieces it puts small pieces of metal
in the oil which will contaminate all the bearings in the unit.  It's a
really good idea to replace all of them while you have everything
apart.  Unless cost is a really limiting factor it's best to do a total
rebuild.  It's good insurance against future problems and will save a
lot of work later.     My   $ .02  Bill   66&67spls in N.M.

Kyle Hagemann wrote:

> Hi all-
>
> I've got the five speed out of my '69 2000.  The cause of
> trouble (I lost first and second gears) was obvious - the
> synchro ring BROKE clean thru, jumping up on the inner
> guts of the synchro assembly.
>
> So the need for a new one of those is obvious. :-)
>
> The age-old question of "how do you spot a worn synchro"
> has bitten me as well - second looks 'pretty good', first
> is 'pretty toast', third and fourth look good (points
> are still pointy) and fifth looks brand new.  The trans was
> out and apart about a year ago, don't know exactly what for,
> maybe a fifth gear fix?
>
> Anyway, the other piece that looks like is hatin life is the
> 1-2 shift fork.  As the synchro ring cracked and jumped
> ship, the ring took on sort of an oval shape.  Spinnin round
> and round on its last dying ride home, it spread the fork
> wider.  The 3-4 fork has about 1/16" slop, maybe less.  The
> 1-2 fork has closer to 1/4".  Can it simply be whacked back
> into shape, or should I get a new one?
>
> Finally, there are a few chipped teeth on the mainshaft's
> second gear.  It's hard to describe, but three or four
> of the teeth are chipped on the edge closest to the synchro
> ring.  How big a deal is this?  The chips are only on the
> corners, they aren't complete missing pieces of teeth.
>
> That's the extent of the damage, but I haven't disassembled
> the main-/counter-/tail-shafts yet.  A premature question on
> reassembly - if the trans was shimmed properly, and I don't
> replace any bearings, and I use the same snap rings in the
> same locations, will I need to buy a shim kit for it?
>
> Should I take the whole dern thing apart, and rebuild it
> for real?  Or should I fix the broken/worn parts and button
> it up and get on with my summer?
>
> For the interested, here's the history as I figure it-
> 1) trans disassembled for unknown repairs prior to purchase
> 2) felt real good for a while, then
> 3) second gear synchro gets lazy, requiring double clutching
> 4) 'dog-shift' from 5th to 1st, whack-bang, cracks the synchro
>    ring, tranny feels pretty rough from there on out...
> 5) first and second gear synchros basically quit, double
>    clutching up and down,
> 6) worse, quit using second at all, and poorly double clutch
>    first enough times to chew up the synchro,
> 7) park it, and stop the dieseling with a hurry-up shifting
>    into first gear, B!A!N!G! the synchro ring jumps its track,
>    graduating from cracked to split and unseated.  The trans
>    makes some real nice rubbing, interference type noises,
>    presumably as it widens the 1-2 fork.
>
> Does that seem reasonable?  My only hesitance to embrace this
> story is why #3 happened - why did the second gear synchro get
> lazy?  When did the second gear teeth chip? (#4 maybe, as it
> jumped gears?)
>
> TIA for any input, sorry to be so long winded...
>
> Kyle
> ps- came up with an interesting way to keep track of bits and
> pieces - a big hunk of cardboard and a pen - poke holes in the
> cardboard to hold bolts, nuts, shims, etc, and label 'em with
> the pen.... too easy!
>
>        ____  Kyle Hagemann, Born-Again Grease Monkey From Beyond
>    _.;(____\____    72 240Z, L28/E88/SU, 5sp, all poly - Z Beast
>   |  _ |   |  _'@`, 71 PL521, LZ22, SUs, 2" exh, 4spd - The Hulk
>   `-(#)------(#)-<  69 2000, engine/trans out, making a big mess
> ------------------- 84 Maxima, Tokicos/ST springs, 237K - Mr Max
> http://www.sonic.net/~kyle  http://www.sonic.net/~kyle/cars.html


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