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Knocking in transmission

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SMGoose

SMGoose

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When I first got my TR4 a couple months back, it grinded into 2nd and 3rd. I immediately changed the gearbox fluid; it needed it pretty bad and some metal shavings clunked into the drain pan. With the hypoid gear oil, it shifted better but still had problems downshifting into 2nd.

Now, while settling my misfiring issue, something must have jarred loose in there. I heard a few loud bangs from under the car and now, at idle in neutral, there's a steady knocking that stops when I push in the clutch. Is it rebuild time? Bearing broken loose? I fear the worst here.
 
Not sure, but it might just be the clutch.

At any rate, and not to make light of it, I couldn't help but remember these guys:

 
My guess, and its only a guess, is that the keeper on the layshaft is broken and the layshaft is slapping around in ways that are not good. Have to pull the tranny and remove the tailpiece to find out. The keeper is a square metal tab, # 129938, that fits into a slot at the rear of the layshaft. If it breaks, the layshaft can slip towards the tail of the tranny and may move far enough to misalign various bits. I found a broken keeper when I rebuilt my TR4A tranny. If that was my car, I'd not drive it and pull the transmission.
 
The first two posters both show signs of serious issues although I am not qualified to give a diagnosis on either.
However, those were big shavings that would clunk in a drain pan. Teeth off gears? Loud bangs? I agree don't drive it, gearbox probably gonna need to come out.
 
Interesting, I don't recall seeing the video before. But as with so many other groups, their "studio" version sounds better:
https://www.snic-braaapp.org/UAT/media/Tappetstry/Spinal Tappets - Losing My Transmission.mp3

Unfortunately, SMGoose, it sounds like it is definitely closer to dying entirely. I'd guess multiple broken teeth on the countershaft or perhaps the input shaft. You can keep driving if you want, but it will only get worse from here.

Wish I had the photo of "Uncle Jack"s OD transmission spread all over the pavement (which ironically enough was brought to us by the same club that did "Losing My Transmission") to insert here, but I don't. Does anyone else have a copy?

DSCF0038.jpg
 
Haha thanks, Mickey. That'll give me some entertainment while I'm tearing out my gearbox.
I kinda figured it would have to be taken apart. Any links to helpful guides or manuals? Good, affordable parts suppliers? I've never done transmission work before.
Looks like this calls for a few more drinks tonight! Especially before I tell my fiancée!
 
TR3driver said:
Close enough. Thanks, Mickey! I see in the next month's newsletter where they think that possibly one of the Torrington thrust bearings (which TRs don't have) came apart and a bearing roller locked the layshaft.
Click to expand...

You're welcome.

For those who are interested, John Macartney, who made the trip, wrote a book chronicling his journey. In the book Joe Pawlak and crew (who were charged with the restoration of the Stag) tell the whole story about the tranny mishap. John also writes a good deal about Post Traumatic Stress Disorder, which was the cause that benefited from the event. Great reading!

More here:

https://www.standard-triumph-books.co.uk/
 
Thanks again, fellas. I honored you all through drink last night. Looks like my hopes of getting this car squared away before the semester started back up have officially been dashed (I'm in grad school). I don't know when I'll be able to get to it but I'll let you all know how it goes.
 
Hey - best wishes in grad school! What's your subject area?

By the way, did the car show any transmission problems or noises when you made your pre-purchase inspection?

Tom
 
If a gearbox is in good order, it is not terribly hard or expensive to refresh it. Unfortunately, it sounds like you will be looking for at least a couple new gears and bearings...that gets pricey. You may want to look around to price a decent used box to reduce the time and cost.

JMHO
 
Hey Tom,
Thanks for the well wishes. I'm getting a PhD in French, studying Cajuns/Louisiana French.

Suffice it to say, it's become pretty apparent that I got a raw deal on this car and the purchase has become a sore point and a blow to my pride. I drove the car in a very small town with 20 mph limit and a lot of stop signs. I should have took it on the highway, but I was unfamiliar with the surroundings. Shifts were slow and I was probably too careful with the car. It only grinded once going into second, but I blamed that on myself at the time.

At any rate, I feel pretty naive about it all in hindsight. On the bright side, even with all the repairs I've done, I still haven't hit my initial budget. I fully expected to have to do work on the car, just not so much so soon! I've lost enough sleep over it and am just looking forward to that day I'll actually get to enjoy it. Guess I'll be more prepared for the next purchase ;)
 
SMGoose said:
Hey Tom,
Thanks for the well wishes. I'm getting a PhD in French, studying Cajuns/Louisiana French.
Click to expand...

Well, if you need any research on Cajun food, I'm your guy! Product of Shreveport and New Orleans.


:cheers:
 
Scott - tu as bon copain mechanique? Si tu trouves une boite vitesses, peut-etre qu'il t'aiderait. La bataille n'est pas perdue!

And for the rest of us ... you have a good mechanic friend? If you find a gearbox, maybe he could help install it. The battle isn't lost!

Soit de bon courage!
Tom
 
Don't worry Scott...buying a 50 year old car is very different from what mainstream buyers do. You got a beauty, and if it still runs at that age you are ahead of the game! I personally don't think you were taken. It's all part of the game, and worth it once you hit the highway on a nice spring day with a vintage Triumph!
 
TR3driver said:
I agree. In addition, you could consider just dropping it in "as is" and working on a rebuild later.

This one might be a good candidate
https://www.ebay.com/itm/Triumph-TR...722&pid=100011&prg=1005&rk=2&sd=271135351980&
Click to expand...

You guys may be right. I just worry about getting duped again.

Mickey,
I thought with a name like Richaud, you might be from my neck of the woods! I'm a Cajun from Lake Charles and lived 6 years in New Orleans while at Tulane.

Je me sends vraiment chez moi ici, merci, Tom! Malheureusement, pas de potes mécaniques :/
No mechanic friends, unfortunately. Sort of on my own with this one and not a whole lot of workspace. Might have to make some new friends quick!
 
Scott - there are likely some TR owners in your area. Might be available to help. I know you're still working on the engine problem. Adding gearbox headaches to the mix can be overwhelming if you've never been there.

Tom
 
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