Re: [alfa] Is this transmission toast?

[bearbvd@xxxxxxxxxxxxxx (Greg Hermann)]

At 11:59 PM 6/21/04, Kevin Trent wrote:

What happened is that one of the bronze bushes between one of the gears and
the main shaft tried to sieze to the main shaft due to lack of oil. Thus
the noise and the feeling of 'drag'. (If it had fully seized, the tranny
would have been essentially trying to be in two gears at once--fifth, which
you had engaged, and the one that was trying to seize, and thus locked
solid, unable to turn at all.)

It is most likely that it was either first or second gear that tried to
seize to the mainshaft, as these have the greatest speed differential
relative to the main shaft when in fifth gear.

There is a LOT of heat involved when this happens. It wouldn't be too
surprising if both the main shaft (pretty likely) and the gear involved
(less likely) are toast.

The strength of the main shaft is likely compromised due to softening from
the heat.

Fill it with oil and baby it for as long as you must, but plan on
rebuilding it with some parts needed pretty soon.

Where was it leaking ??

Greg

>This past Sunday I drove my '73 spider to a bike race 190 miles away.  I
>got a late start and had to drive fast (got there in 2.5 hours) and with
>two bikes on the trunk and the top town, it was pretty noisy on the
>interstate at 80. This drive was early, at 7am and the temperatures were
>cool and the car ran fine.  But in the heat of late afternoon on the return
>trip the car began to make an unholy sound from the transmission - the
>sound of a screeching bearing going bad.  I nursed the car back home, with
>the trans having the bearing screech come and go as I drove the on the
>interstate and adjusting speed to eliminate or minimize the transmission
>sound.  At times smoke would emit from the shift boot, and if the screech
>got real bad (it came and went with varying degrees of severity), I could
>feel the car slow as if I had pulled on the emergency brake.
>
>But I made the 190 miles home.  The trans felt hot, but nothing I could
>really point to as abnormal and it didn't stink of hot burned oil.  Tonight
>I drained the trans oil and only got about a half quart to come out.  I did
>not see any obvious amount of metal in the oil. The magnetic drain plug did
>not have an unusual amount of metal on it, but  I stuck my finger into the
>drain and wiped it around (it felt "gritty"), and when I wiped off there
>was obviously metal flakes from this bottom sludge.  Unfortunately, I was
>unable to drain the trans when it was hot, so I'm not sure if metal residue
>just settled in the bottom of the trans rather than draining out with the oil.
>
>SO it appears that I drove the car too far and too long and too hard with
>too little transmission oil, and a bearing has gone bad.  What to do?
>
>My initial thought is to refill the transmission with 30 or 40 (or?) weight
>oil and do a little test driving to ascertain (a) if the proper amount of
>oil will eliminate the bearing noise and (b) if this thin oil will wash out
>the metal residue from the transmission.  If the noise is eliminated, I'll
>drain the thin oil and replace with proper gear lube and just drive it.
>
>Or is this just wishful thinking, and the transmission has been ruined, and
>I might as well just replace or rebuild it?
>
>Opinions or experiences with such situations?
>
>thanks, //kct, Powell, TN
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