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Tranny rebuild success!

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Jerry

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My wife and I just finished rebuilding our side shift transmission. We watched the video on Youtube a few times and decided to go for it. There were a few missing hints but we figured it out. The Transmission is not sitting with new gears, new layshaft, new syncros, new needle bearings, new thrust washers and everything sealed up tight. Now on to the Overdrive! By the way, having a second set of hands on the transmission was very useful. It would have been a lot easier without needle bearings. I sure wish I could have used caged bearings.

Any hints on an OD?

Jerry
BN4
BJ8
 
Jerry said:
... There were a few missing hints but we figured it out. ...
Click to expand...

You make me curious ;-)

Hans
 
Hi Jerry,

can I throw a few things at you that I learned from doing my rebuild twice?

Where did you get the synchro cones from- Many of the replacement ones are not well made and don't work. Even the expensive (DW) ones still need a fair bit of fettling to get them right. If the mating surface in the cone is not perfectly matched to the gear then it won't have any baulking action = grinding gears. Have a look in the archive, I posted some pics of the problem.

Did you check that the hard plastic pad is in the bellhousing cavity where the selector shafts stick forward? If it isn't there the 3-4 hub will fall apart as the shaft moves too far forward without the spacer.

Did you look very closely at the inside of the lay gear at the back? Normally the hardening goes through at the very end (back end) and the solution is to have 1st gear cut off the laygear and a new one welded on. Various sellers have them for exchange on Ebay but it is better to have yours rebuilt as the gears do bed-in to each other.

For the OD- firstly take lots of photos of the stripdown. Read the Buckeye Triumph website article about getting the OD pressure to the correct level, there are three steps and it is quite important. You can spin up the trans with an electric drill and check the pressure comes up to 390psi on a gauge. Saves a lot of time pulling it out again.

One thing that isn't immediately obvious is that the bore tube that holds the accumulator spring comes out and reveals a whole load more gunk trapped in behind it. I used external snap ring pliers wrapped in a large rag to grip the inside of the tube to free it. Replace all the orings and solvent wash/compressed air dry until no more crud comes out. Also put thread sealant on the tail shaft nut, it leaks oil down the thread otherwise. Other than that the OD is mostly just bearings and seals.

Andy.
 
Hans,

the video did not explain how to get the shaft into the layshaft after all the other gears are in place. With Needle bearings, this is tough!

I also found lots of grim and metal bits lodged in the side plugs. I took these out to clean.

Andy,
Thanks for the hints. I bought my parts from AH Spares and DW. I did read your hints, I hope I did them right for the syncros. By the way, the pictures in your previous posts don't show up any more. I did save them to my computer though. Thanks for the comments to seal the leaks. I did make sure the rubber pad is in place in the bell housing. I learned that the hard way prior to putting the bell housing back on.
I am curious as to who you get to reweld your layshafts, in the US??

Jerry
 
Thanks to you both for the additional information

Hans
 
Hi

This is timely. I've got the gearbox out at the moment, with the engine now in the final stage of rebuild, and to reseal underneath, engine bay etc.

Question is what size is the plastic spacer in the bellhousing? I didn't see one but found a small, obviously home made lozenge shaped bit of hard plastic about 1/16" thick on the garage floor. Could this have been someone elses home mae piece.

I would be grateful for a photo or description of this so I can make one - the other has disappeared.

Secondly, where do I find the video or info regarding gearbox wear/repair mentioned above. I know nothing about gearboxes but I found a "shim" approximately 3 1/2" outside diameter hanging loose off the input shaft -?leftover by a previous "rebuilder". I get approximately 065" up and down movement and 035" sideways movement at the end of the input shaft, but no "in/out" play. Movement can easily be seen in the ball bearings of the driveshaft bearing. I've not attempted to remove any parts or loosen the nut/lockwasher.

Should there be such movement here or are these parts worn?

PS. I've looked around the site and on you tube without success.
 
https://www.youtube.com/watch?v=mUThETcnZ2k
There are three videos that you should watch all done by the same guy. One on OD and two on the transmission. Very useful.
OR=- put in "Austin Healey transmission" into the Youtube search and you should find them also.

I am not at home right now but I can take a picture of the rubber piece when I get home. My memory says it was 1/8 inch think but I should check first.

Jerry
 
Thanks Jerry

I watched the vids, a cool Swede, and the problem of the bearing plates is solved (blush!)- now to find the missing bits. I see the plastic pad and will cut a piece of stiff mouse mat or similar to fit.

I wonder if this chap got an answer to his input shaft problem. Similar to mine but mine is nowhere near as bad - probably normal in comparison.



https://www.youtube.com/watch?v=Dwb5YsiprSs&feature=related

I spent an interesting hour or so flicking through all the other clips.

Some good stuff on You Tube.
 
I saw this video also, but it gave me more questions than answers so I used the others. I think the videos did really help me understand that the transmission is really all mechanical (ignore the overdrive) and parts can be replaced. All you need to do is remember how they went together and measure the tolerances. I was also happy that I only had first gear and the layshaft that were damaged. Beware teaching your daughters or loaning the car to others who don't understand when you say "NO SYNCRO in FIRST GEAR".

There was no issues with the shifting forks that would have resuted in the chewed up first.

Jerry
 
Well if he was realy sucessful it will show up when he runs it.---- :laugh:
 
Just finished the Overdrive. I had to make a shim as The thrust washers plus spacer was too tight. The process of lining up the spines was more difficult this time. Took about 5 trys to get the OD mated to the transmission. But it is nice to have it done.

Jerry
 
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