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General TR What to do in a "a" type Latest

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Got_All_4

Got_All_4

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What to do in a "a" type up-date

Well I decided to use the A type tranny in my Tr3A and it looks like the gear box is in top shape. The car it came out of is a 69 TR6 and the tranny must have come out of a bone yard because of the 1970 Triumph overdrive markings in the bell housing. The car was driven into a local body shop in 1982 for a paint job and the owner never came back. That's how I got it.

After sitting all those year the seals got to be dried out and whatever oil is inside there's got to be varnish and what ever inside. So my question is what should I do to update it with new seals and gaskets. Plus what ever you guys suggest and where to get everything from. I have a local Triumph tech to guide me. Plus he just did one so his skills/memory has been updated.
 
Re: What to do in a "a" type up-date

If you're going to open it up to change seals anyway, I would probably have a look at the countershaft bearings and thrust washers. They're a known weak spot, and may be in the process of failing even if the gearbox was working "fine" before. Ditto for the thrust washers in the OD (especially the little one trapped inside the planet gear assembly).

But if you're feeling lucky, just change the oil and check the OD operating pressure.
 
Re: What to do in a "a" type up-date

The only luck I have is bad luck. Any suggestion where to get the parts? like I said I've never done a overdrive.
 
Re: What to do in a "a" type up-date

Each of the big three vendors carry, some, but not all, of the OD parts. The funny thing is they each have different parts too from each other. The durable parts are pretty regular on EBay.
 
Re: What to do in a "a" type up-date

For what it's worth, I bought a used TR4A overdrive a few years ago that had sat many years. I drained it then bench tested with a drill and found it wouldn't engage/disengage smoothly. I flushed with ATF and ran it through bench test cycles and it clean right up. Fill it with gear oil and it worked just fine. Only seal changed was the rear output shaft seal.
 
Re: What to do in a "a" type up-date

If they don't have it, another place to try is https://www.overdrive-repairs.co.uk/
Best to contact them, as they frequently have parts not listed on the web site.
 
Re: What to do in a "a" type up-date

John rebuilt my OD gearbox this Fall for me (super nice guy). As you see from his website, his webmaster (and friend) passed away this summer and he was hosting John's site. The webmaster's wife shut down the webserver and poof, gone was quantumechanics.com. The last time I spoke to him he was rebuilding his website in his "free" time. Although his site is down, his business is thriving.....call him at 203-463-8299 or I think his email still work (john@quantumechanics.com)
 
Re: What to do in a "a" type up-date

Thanks for the info. I've read posts here where some ordered rebuild kits and everything was thrown into a bag and not labeled. For someone who never did this before that could be a nightmare. Too bad about Johns friend. I'm horrible on this computer stuff and that would shut me down if that would happen to me.
I was tempted to do what Randy did but I need this to last. Getting too old to R&R a tranny/engine/rear end in a few hours and rebuild. What use to take a day now takes weeks or months so that's why this has to be correct going back in.
 
Re: What to do in a "a" type up-date

Not what I was wanting to do but looks like the gear box isn't in the pristine shape I thought it was. I can grab the input shaft and wiggle the shaft up and down and side to side. Have to say the spigot bearing is worn. Hopefully not the shaft. So Randall looks like I'm going to do the counter shaft thrust bearings and anything else I see. Will be taking the overdrive valve body to get sonically cleaned tomorrow. Hopefully this weekend we get to access what needs to be replaced.
 
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