transmission apart

LopezCarguy

LopezCarguy

Senior Member
Now what?? How do I tell if parts are serviceable or need replacement..after cleaning bearing they seem smooth spin with air and sound good..gears look good... not wear to point ..I will take pictures next outing to shop.. I would like to have a good trans..and not have to take it out again...Dick
 
Do you see any contact wear patterns on the gears? I don't know about your specific transmission but there should be thrust bearings with definite clearance limits.

I plan to get the Van Pelt book on transmission rebuilding before I start my project. The book claims to provide the sort of detail you may be looking for.
 
Go to the web site Bob C above has provided. There are several articles that should help you. I suggest you replace all five bearings. There is a Bratton's part list. The front and rear ball bearings are foreign made, but of good quality. They are sealed on both sides. I remove the seal on the inboard sides so the lube will reach the elements. Be sure and orient the oil baffles carefully. The assembly of the transmission is not difficult, but be careful, Henry laid some traps for the unwary.

If the nose on the input shaft is worn, but the rest is serviceable you can send it out for repair as it is cheaper than replacing it. Contact Jim's Automotive Services (a Model A repair shop) in Costa Mesa, CA. Jim Nichols owner, 714-546-2969.

Tom Endy
 
what made you take it apart? was it noisy? jumping out of gear?

Tom E is the high authority on diffs and trannies. If he says it, it is
 
LopezCarguy said:
...after cleaning bearing they seem smooth spin with air and sound good..
Click to expand...

Damn Dude. That's a good way to lose some fingers. Spinning an un-lubed bearing with air may be fun but WHEN it seizes your going to be in a world of HURT!! :eek::eek:

If nothing else you could damage the bearings.
 
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I knew an old mechanic that lost an eye when spinning a bearing with air when the worn bearing exploded . I wouldn't do it .
 
If the transmission isn't jumping out of any gears and there is no obvious damage, I replace all of the bearings plus the cluster gear and reverse idler shafts and have never had any problem. Les Andrews has a lot of ideas that many take for gospel . I have never had a problem reusing the main input shaft if ithe transmission wasn't jumping out of gear. Some measure the end of the shaft where it enters the pilot bearing and if it is the least bit out of the specs that Les lists they either throw it away or replace it entirely. If the nose of the shaft is way out of specs, an under size pilot bearing can be used or it can be turned down and sleeved with a bushing. I've never had a problem with the input shaft if it wasn't jumping out of high gear .. If the gear on the input shaft mates good with the second and high sliding gear, this is what I go by when using used untested gears. It is an aquired feel that I learned as a teen ager that I can't explain. A person can spend a lot of money unnessarily on new gears. The model A isn't a Rolls Royce and the crash box transmission will never be as silent as a modern car . My main concern has always been that the transmission didn't jump out of any gears . The original diamond gears are very robust and will usually last a life time if the bearings and bearing shafts are not allowed to become worn so that the gears drop out of alignment .
 
when you consider the cost in time to pull, rebuild and replace the trans, replacing all the bearings is cheap insurance that you will not have to repeat the job as long as you don't cut corners somewhere else.

Post some sharp pics of the gear faces so we can see if they're good.

Also, inspect inside the pilot bearing bore of the drive gear to see if the hard facing is still good. Likewise, check the main shaft pilot bearing shaft hard facing too. The gears should slide slowly down a lubed main shaft of their own weight when the shaft is inverted. If they drop fast, they will not hold in place when you drive. The flywheel pilot bearing should be a smooth slip fit with no wobbles. If that pilot is worn more than .002 it needs repair. A good shaft measures .668.
 
I do not have my transmission apart yet, nor am I likely to in the near future, but I have a problem shifting from 1st to 2nd on occasion. I am well versed in double de-clutching having used the technique for some 50 years since learning to drive in a 1927 Austin Seven back in the day.

I know many disagree but I tend to double de-clutch up and down the gears as this is what I was taught, right or wrong. I do this even on our more modern collector cars with fully synchromesh transmissions, not only does it sound good, but done properly reduces the wear on the synchromesh rings.

The problem usually manifests itself if I hang onto 1st gear for a longer than usual period such as crossing an uphill intersection over an eight lane road close to home. I have tried a single de-clutch and a double de-clutch in this kind of situation. Neither seem to provide an answer. I can usually select 2nd gear when the car comes almost down to walking pace. If I shift up early, the shift is usually faultless.

Although somewhat embarrassing in rush hour, the problem is not about to make me tear the transmission apart tomorrow as there are no other nasty symptoms.

Any suggestions?

Ian
 
One of my A's sounded like a broken down threshing machine when I bought it. The only bad part was the small roller bearing that fits between the input and output shafts, so that's the only part I replaced. All the rest of the original parts looked NOS. That's the first picture.

The second picture is a good spare ****** I put together from all good original parts. I painted the inside with Rustoleum red oxide primer.

The third picture shows pitted grears. This is the cutaway at the Model A museum at the Gilmore museum in Hickory Corners, Michigan.
 

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replace the bearings thats part of freshening it up on the bench.. buy the parts tom E has mentioned on his tutorial
 
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