OD mainshaft.

[bkasl]

mainshaft for a 1725cc 4 syncro transmission.. Brent

 

[robertg]

Brent

Did you ever find a mainshaft for a 1725 OD synchro transmission, I am also looking for one.

Thanks bob

 

[bkasl]

Nothing, even overseas!

 

[Alpine Bob]

I thought someone on the forum was saying they had a dozen or so transmissions, maybe you all will have to resort in buying a whole transmission. Just a thought or my 2 cents worth.

 

[alpine_64]

Finding a full sync OD shaft is almost impossible.. and then you have to hope its not junk.. did that for years with no results. Your best bet is to buy a full OD transmission. Another option is to get a non-sync OD shaft (for some reason they seem more obtainable) and splice it with the non OD full sync shaft. Has been done many times down under.. i decided aginst this route and just went and bought a whole box in the UK and sent it over.

 

[SIVAllan]

I thought someone on the forum was saying they had a dozen or so transmissions, maybe you all will have to resort in buying a whole transmission. Just a thought or my 2 cents worth.

Hey Bob,
Don't you have a fine spline OD unit ??

I have a fine spline syncro gearbox, mebbe we could pair the two and offer them ??

Allan

 

[Alpine Bob]

Allan,
That would be a great idea, but I sold it already. OH WELL!

Hey Bob,
Don't you have a fine spline OD unit ??

I have a fine spline syncro gearbox, mebbe we could pair the two and offer them ??

Allan

 

[Rootes 66]

By far the biggest problem with buying a second hand mainshaft is that it'll likely have damage to the end bearing surface that the 23 rollers sit on that fits into the Primary shaft, I haven't tried this but wouldn't it be possible to get a m/c shop to say take 10 or 20 thou off that dia to clean it up and get some Oversize rollers made to accomerdate,
Pete

 

[puff4]

The proper, and frankly pretty easy, fix for that is to have it turned down and to press a new sleeve on. It's a common machine shop repair and the sleeves are available in nearly every size you could need. Then you just pop in the standard bearing. The cut-down is so minimal that you don't really affect the strength of the shaft to any appreciable degree.

 

[jumpinjan]

It's the rear journel (enters the OD unit) that usually gets screwed-up. They all look like a backyard mechanic took a hammer to the end of the shaft. Probably, to get the shaft out of the rear ball bearing.
Kevin is correct on the repair process. I use hardened drill bushings as the repair sleeve for my damaged shafts. A precision grinding shop, here in Dayton, performs the job for me and they do a great repair job. I have saved many shafts getting them repair in this manner.
(This was a good tip that Tiger-Tom gave me!)
Jan

 

[Jim E]

Just a thought, could Delta Camshaft or Standard Crank spray weld it up and turn it to the stock size? I am guessing they could but would they. When I have had Standard fix a rod journal it usually adds about 40 bucks to the cost, not sure how that would compare to turning and using a sleeve or such. Anyway just a thought.

 

[puff4]

Jim, they probably could spray and turn the unit down, but in heating the shaft, as they would need to do for this process, iits hardness could get fouled up. Plus the new bearing surface would be of questionable hardness, too. However, with the cut-and-sleeve method the work never gets heated, so it retains its original hardness, and of course the pressed-on sleeve is already the proper hardness for a bearing surface. All in all, I think the sleeve method is the cheapest and most reliable fix for a galled needle bearing race. BTW, this also works for an internal (female) race as well (like the one in the input shaft).

 

[RootesRacer]

Anyone have specifics on the cut and sleeve method?

I have an early OD mainshaft the ate its input rollers.

I knew someday I would figure out what needed to be done to salvage it, but didnt know what specifically to ask a machinist to do.

 

[puff4]

I wouldn't worry about the specifics... most good machinists are used to doing this operation, as it's very commonly done... and they should know where to get the sleeves, too. I get mine from Bearing, Belting and Drives here in PA but I'm sure there are other suppliers near you.

 

[RootesRacer]

About what should it cost to do this?

 

[puff4]

I should think no more than $60-80 per repair. Most of what you're paying for is lathe setup time. The whole thing should take little more than 30 minutes for a competent machinist.