Leaking transmission
 

The trans on my pickup has been leaking, it leaked about a 6in diameter pool in a month while I was away.
I decided to look at it, it was coming from the back of the cluster gear shafts I did an oil change to the 600 wt oil, the trans was way quieter ,but still leaked.
So today I pulled it out and stripped it down.
I find there is a .006 gap between the shaft and housing, the shaft is .750 but the housing is .006 larger.
My fix tomorrow is to clock the housing up on the mill, bore it out .080 oversize, then turn up a sleave and press it in ,then bore that to the shaft size.
Will post some pics tomorrow on the job
Lawrie

Re: Leaking transmission
 

Given your size you're probably talking about either the cluster shaft or the reverse idler. I like to turn a "groove" and fit an 0-ring on the shaft - although the parts houses sell a "cover/gasket" that can be used in this area.

Cutting a groove in the lathe I discovered how "hard" the cluster shaft is. Case hardened, perhaps. I finally resorted to doing the groove with a tool-post grinder - not my fave since it puts grit all over the ways of the lathe.


Joe K

Re: Leaking transmission
 

The vendors sell those two shafts with the groove already cut into them

Re: Leaking transmission
 

At that time (20 years ago?) the grooved shafts were not available - and its a logical extension and I considered it far better (likely tighter) than the cover/gasket.

In this case it appears the hole has worn. There is nothing to keep the cluster shaft from turning other than the friction in it's hole. Some rebuilder instructions look to have the shaft "tight" in the hole - so tight it won't drop of its own weight when you hold up the case. Tightening the hole IS probably the best initial solution. I would go on to a positive seal since that's the part that Henry obviously left out.


Joe K

Re: Leaking transmission
 

OK, but we are in the present day and the grooved shafts are available now so why grooves them now?

The cluster shaft and reverse idler shaft should not be turning there is a retainer at the back of the transmission.

https://www.fordbarn.com/forum/attac...8&d=1742995619

Re: Leaking transmission
 

Worthy query. It is well you brought it up. That is the point.


Joe K

Re: Leaking transmission
 

Even my Mitchell Transmission leaked from those sfafts. I installed the "Transmission Seal Kit" to stop the drips. https://www.snydersantiqueauto.com/p...8999&cat=41756

https://www.fordbarn.com/forum/attac...1&d=1742996197

I don't like drips... so dry it is rusting.

https://live.staticflickr.com/7626/2...b2228fbbd2.jpg

Re: Leaking transmission
 

Job finished today,
bored and sleeved the trans housing and then bored the sleave to .7505 inch.(sleave made from old ford axle shaft )
Came out really nice ,
Tomorrow will reinstall the trans,

Re: Leaking transmission
 

Lawrie what about a counter bore and put a small seal on the shafts? Is there enough meat in the case for that? I looked at that on the V8 cases and think it would work.

Re: Leaking transmission
 

Once I have sleeved the bore back to the correct size, there is no need for an o ring.
I have resleaved a couple of my spare V8 boxes and they dont leak after, my 33 has done a pile of miles with one fitted,
There would be enough metal to fit an o ring in, but on. the model a case the bore is only .700 long so it would reduce this by the thickness of the o used.
my sleave was .830 OD ,there would be enough room on the boss of the case for a seal.
Lawrie