T-20 Leaking

[nate52]

I have a t-20 in my 1973 attex and had pulled it out of my machine chained the fluid in it and put it back into my machine. After letting it sit while working on everything else on it trying to get my restoration on the machine completed, the tranny had leaked out nearly the entire quart of fluid it holds into the bottom of my hull over about a period of a month. It was leaking from the plungers and so I called RI and bought 2 new gaskets for the case and also bought 8 plunger o-rings which was suggested. After tearing into the tranny and having it all apart on the bench now ready to put back together i have noticed that there are only one o-ring per plunger in my transmission or 4 total for all 4 plungers. Is this common for older models of the t-20?
Also was glade I took on the task of doing this myself because I now know how simple the setup in these transmissions are and am pretty sure I could put this thing back together in my sleep.

[Uncle Vin]

Yes, the single o-ring is common. You could upgrade to dual o-ring plungers. At least consider it for the bottom plungers.

[racerone3]

you can have a local machine shop cut a second set of o-ring groves in the plungers rather than having to buy new ones

[nate52]

how much are the new ones and how much of a necessity is the second o-ring on the bottom plungers?

[jeffery9076]

mine did the same thing i did not know about the double o ring plungers. DON TOLD ME USE THE DOUBLE O RING ON THE BOTTOM ONLY THE TOP WILL NOT LEAK. it pis??? me off but but i advise you it will only get worse and it is to hard to detrmine how much fluid you lost

[nate52]

so are you still having problems with the double o-ring plunger? or did you not use them and are now having problems because you only have the single o-ring plunger in your machine? Either way my plungers will all have new o-rings on them.

[jeffery9076]

No i still never fixed mine still the single i just top the fluid off but it makes a mess with the leak. If i had time to i would tear it down and fix what the tranny fluid messed up but i have to finish the wifes thunderchief first. I beleive someone posted recently about putting a breather on there top tranny plug and his quit leaking thought maybe the heat affects it.

[racerone3]

No i still never fixed mine still the single i just top the fluid off but it makes a mess with the leak. If i had time to i would tear it down and fix what the tranny fluid messed up but i have to finish the wifes thunderchief first. I beleive someone posted recently about putting a breather on there top tranny plug and his quit leaking thought maybe the heat affects it.

the top plug SHOULD be vented, if not you risk blowing one of the seals in the trany when heat and pressure build up inside. if an o ring is torn it will leak no matter what you do. i would go with the double o rings... if one tears you still have the other to fall back on.

[nate52]

alright thanks for everyone's input. I priced new double o-ring plungers from RI today and am now going to check with my local machine shop whom I have already done some business with for other parts on my machine. I am definitely going to go with the double o-ring's on the bottoms plungers though, and I have already checked my top plug to make sure it is unplugged when I changed the fluids on the tranny on it the first time.