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Is a Triumph overdrive tranny all that?

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My neighbour has a lathe with a 10" diameter faceplate. He set up the overdrive on the lathe and drove the input shaft with the jaws on the faceplate. He made a plate to keep the oil in the overdrive from leaking out and none spilled or splashed out. The lathe had enough power to do the test and we could manually "click on" the overdrive by simply pushing down on the lever arm on the right side on the casing. We could hear and see the output shaft change speeds up and down as we "switched" the overdrive on or off
 
Adrio said:
When I repaired my O/D I used a 1/3 HP motor and a belt to drive the output. I used corks to plug all the holes in the forward part of the overdrive and that way I was able to test it before I even attached it to the gear box. It worked great. I tested it the same way once the unit was mated to the gearbox as well, just to make sure.

I have some pictures of this if you are interested let me know.
Click to expand...

I for one would love to see photos of this test.
 
Don Elliott said:
...We could hear and see the output shaft change speeds up and down as we "switched" the overdrive on or off
Click to expand...

That sounds like real fun. Hope you made motor noises as you went back an forth.
 
i want another gear and after reading all the great info here i'm going to look for an a-type to mate with the existing gear box on my irs. so assuming i will probably end up with a blind e-bay purchase of the od whats the worst case somewhere north of an anchor?
 
sail said:
i want another gear and after reading all the great info here i'm going to look for an a-type to mate with the existing gear box on my irs. so assuming i will probably end up with a blind e-bay purchase of the od whats the worst case somewhere north of an anchor?
Click to expand...

There's a guy I've been chatting with offline, who has two A overdrives available. I'm not sure if he's reading the forum: he announced parts on the BCF Parts mailing list a week or so ago.

I have just ordered a J type from New Zealand /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
two things. one is you need the O/D unit as well though you will need a new main shaft.

Second, if my experience is anything to go by, I had a non functioning O/D unit and was able to fix it. Some one in its past had damaged the pump follower that rides on the cam so that it would not pump. Then they removed the cam to boot. I think they had had it apart and did not know about the wire trick used to hold the pump down against the spring until you get the unit presented and almost home against the gear box. Also some of the oil passage ways had been clogged up (which is what I suspect made the previous owner attempt to take it apart.

The worst case it you have most of the bits for a working O/D unit and you will have to hunt down some other parts to make it work. Not an impossible task.

If you go this way try and get the article that use to be on the buckeye Triumphs web site. It was all I needed to figure out my problems.
 
2wrench said:
Julian, I think you outbid me.
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No, that wasn't me /bcforum/images/%%GRAEMLIN_URL%%/blush.gif I made an arrangement with the seller, prior to auction end, that if I bid and someone outbid me, he would sell me one of his units at my original bid price - I think he said he has 12 of them standing by(!). The seller is very accommodating, and answered my (many) questions patiently.
 
I suppose a consideration for me was that I would be wrassling that box into the car all by myself. I was sure I could do it, was also pretty sure I would be stiff and sore for a few days following. Was right on both counts.

Anyway, was worth it to me to be fairly confident that everything would work first time and for a long while to come w/o having to R&R that thing a couple of times. That's why I went with the whole enchilada from John Esposito.

Of course, the bench-testing set-ups noted above sound like fun and could be very helpful is reducing the chance of problems being discovered only after the install.
 
No sweat, Julian. The fellow has a handle on more,
I think. Extended my opportunity to buy as well,
so no problem.

I'm hoping that this is a mod I will be able to do
myself. He says you have to tear into the tranny
to do the upgrade.

Guess we'll be in the soup together, which has seemed
to be the way it's going.

Hope you got your door seal on okay.
 
2wrench said:
No sweat, Julian. The fellow has a handle on more,
I think. Extended my opportunity to buy as well,
so no problem.

I'm hoping that this is a mod I will be able to do
myself. He says you have to tear into the tranny
to do the upgrade.

Guess we'll be in the soup together, which has seemed
to be the way it's going.

Hope you got your door seal on okay.
Click to expand...

I have a feeling that I will tackle this job in the Spring, but I wanted to buy the unit now (a bird in the hand ...).

Doing it in the Spring has the advantage that I can watch and learn from your progress in the meantime Mwahahahaha!

Yes, got the window seals on without any problem.

Today's job: painting the rear panel black and finishing up the fibreglass floor pan repairs I began a couple of days ago.
 
Roit on, Julian, roit on! You are an inspiration.
Think I'll wait till earl summer to put my tranny
together so I can learn from you.

You know what they say: The wise learn from the
(don't say it...) mistakes (auhh, man, I said it), of
others.
 
Guys would $1000.00 for a worn out 1958 parts car with an engine and A type OD be worth the money? It's been garaged for many years. This would mean disassembling the above listed and see what it might require to be used again.

I want the OD for my car but need to decide whether a rebuilt is better then an old one that I can try to rebuild.
Any comments?
 
Just my two cents worth, but you could buy it, swap the tranny with yours and after you are sure the new O/D tranny works sell the whole thing again but without O/D. might be the cheapest way to get O/D, but it will take some sweat equity. It that parts car is local to you then it might cost less in the end then shipping will for some other way to get a parts car.

And in the end some one else will buy the parts car from you and one more LBC will get restored and back on the road.
 
Sounds like a bargain to me. I've done basically that twice now. Paid less, but that was a long time ago.
 
This car has virtually no parts that are good so all that would be usable would be the eng/trans.

By the way I thought I might install the OD on my current non-OD transmission main body. It works great with no noise and is fully synchro.
Can be done, correct?
 
TFR said:
By the way I thought I might install the OD on my current non-OD transmission main body. It works great with no noise and is fully synchro.
Can be done, correct?
Click to expand...
If your current box is 4-synchro; and the OD one is 3-synchro, then you will need a different mainshaft for the swap. Exactly which mainshaft depends on exactly which gears your 4-synchro has. If the gearset is from a post-73 TR6, you may need to either buy a custom mainshaft or convert to an earlier gearset.

May also need some minor modification (with a die grinder) to the adapter plate. ISTR the early plates didn't have clearance for the countershaft end & retainer, but I could be mistaken on that point.

Although within the DIY realm, swapping an OD is not for the faint of heart, as it basically involves a complete teardown of the gearbox (in order to replace the mainshaft). The TR3 workshop manual shows the 3-synchro procedure (which is similar for the 4-synchro box).

Likely you'll also need to do something about the lockout switches, since the later non-OD top covers were usually not drilled & tapped for them. You can either drill & tap your 4-synchro cover, or rebuild the 3-synchro cover using the rails & forks from the 4-synchro.
 
I got the New Zealand Connection O/D as well, 2wrench, I know it is an E-bay no no (but I think they have figured out how to make enough money) but contact him and maybe he can accomodate you, we need to form a support group and work through the install together maybe...
 
Absolutely, Glemon. Holy Toledo! I think what I'm
gonna do with this one is take it to a shop.
I purchased then asked questions (sounds kinda dumb,
doesn't it?) Says a total breakdown is necessary but
I think he supplies a needed mainshaft. This fellow
has some very good comments about doing business with
him. I'm always a bit suspicious of those comments,
though. Are they, like, his brother; wife; son-in-law?

Anyway, please do advise me as soon as your unit arrives,
I am excited to see what you find. I think Julian also
bought one as well.
 
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