Drivetrain Locked Up
 

I pulled my Model A into the garage and the drivetrain locked up. The car will not move forward or backwards no matter what gear the transmission is in. I can start the engine with the clutch pushed in but when I engage the clutch the engine stalls.


What is the best way to analyze/repair this situation?


Thanks.


Bill Lee/Virginia Peninsula

Re: Drivetrain Locked Up
 

Was there a sound when you stopped?

Has the rear end or transmission been acting up or making any warning sounds lately?

Regards
Bill

Re: Drivetrain Locked Up
 

Sounds like you either broke something in the tranny or rear end that jammed the gears.


Mike

Re: Drivetrain Locked Up
 

I broke a 2 piece universal joint at the rivet.
I felt the vibration before stopping, when I started to drive forward from a dead stop the torque rotated the joint half on the remaining rivet. This locked up the entire drivetrain. I thought I dropped a gear locking the trans or sheared something in the spider gears. This was a frustrating but cheaper alternative, hope you find a similar easy fix.

Re: Drivetrain Locked Up
 

Trans stuck in two gears?

Re: Drivetrain Locked Up
 

What happened just before or as it locked up ?

I guess I'd start by jacking the rear and turning the wheels, then removing the transmitter top.

Re: Drivetrain Locked Up
 

I had the drive train on a 31 Coupe. I pulled the rear end and found a broken U joint, put in a new one and reassembled. Problem was still there. I pulled the rear end again and pulled one trumpet off. The end of the drive shaft and the nut had broken off and was jammed between the ring gear and pinion. After rebuilding the rear end the problem was solved. I should have looked deeper the first disassembly.

Re: Drivetrain Locked Up
 

Bill
I would do a couple preliminary checks to help pinpoint what’s going on.
Pull the floorboard and pull the 6 bolts that hold the transmission shift tower into the top of the trans. Make sure there isn’t a shift fork issue and the trans isn’t in two gears at one time. Be aware, never , I mean never start the car with the trans top off as you will coat the headliner and interior with lube.

If all that looks good I would then next see if either rear wheel will rotate with it off the ground. Try both sides. If one turns and not the other pull the rear hub on the stuck side.
If all is well then I would just plan on pulling the rear axle back to check the u joint and then driveshaft condition. You will find quickly if you have a u joint and or rear axle issue.

If there is someone in a local model a group that is rear axle savoy it might be good to recruit them. I’ve done lots of rear axles but I’m in the Midwest. Brent terry is eastern Tennessee and he’s aprofessuonal shop if you don’t feel inclined to tackle it. If you have les Andrews shop manuals they would be advantageous if you wish to tackle it.

U- joints, gears, bearings fail so it is a matter of methodical elimination to pinpoint.
Hope that helped.
Larry Shepard

Re: Drivetrain Locked Up
 

Talk nice to it?

Re: Drivetrain Locked Up
 

Does car have Borg Warner overdrive?

Re: Drivetrain Locked Up
 

Good thought Benson. If he went to reverse and didn’t have OD locked out that would toast the overdrive planetaries. He didn’t advise of that and few run them but you never know.

Re: Drivetrain Locked Up
 

The first thing I'd do is move the shift lever around to make sure the 1-R shift fork is in the neutral position, then do the same for the 2-3 shift fork. If both forks feel like they are in the middle (neutral) position, and it's still locked, then I'd remove the tranny cover.


Remember, the shift shafts stick forward into the bellhousing in first gear and third gear, so the cover won't lift straight up in that position.

Re: Drivetrain Locked Up
 

It is probably simple as a stuck starter drive . Put the gear shift in third gear and try and rock the car backwards . If you hear a click the starter will have unlocked . In worse cases the starter will have to be removed to un lock .

Re: Drivetrain Locked Up
 

Disregard my above post #13 . If the engine will start and run , its not a stuck starter drive . Sorry .

Re: Drivetrain Locked Up
 

Have you eliminated the brakes? In other words does it roll with the clutch pushed down? Just asking.....had an e-brake problem that stopped my forward motion.

Re: Drivetrain Locked Up
 

I had the same thing when I first bought my 29 Tudor. It would roll back, but not forward. The E brake lining was held in place by only 1 rivet, and the drum had a bad bend.