Something let go in the tranny

[Will N]

Was out for a ride on a beautiful afternoon yesterday. It was running beautifully- until it wasn't. Coming down a bit of a hill, I stepped on the brake to slow down. It was then that something let loose, and it sounded like rocks in a cloths dryer! It wouldn't go into neutral when I stepped halfway down on the hi/lo pedal, nor when I pulled the brake half way back. It wouldn't go into low gear when I pushed the pedal in all the way. Like I said, there was something being thrown around in there, as the gears were making a grinding, knocking noise. Had to roll into a driveway, and shut the engine off in order to stop it, because as I mentioned, it wouldn't go into neutral. The external linkage is working corrrectly from what I can see. Ended up on a flatbed back to my house.

I haven't had the chance to open it to survey the damage yet. What are your best guesses on what I'm going to find when I open it up?

[redmodelt]

Open it up and find out.

[CharlieB]

Locked in gear? Doesn't sound like a rear end/drive line problem. Start with the trans inspection cover. Jack up a rear wheel you if can't turn it with the hand crank. I don't think it's further past the u-joint. Something in the trans from what you describe.

[Will N]

Well, took the inspection cover off, and nothing seems to be amiss. I was expecting maybe a broken clutch spring or clutch arm, or broken band spring, but no! No broken teeth on the triple gears, although it sure sounded like those gears were stripping teeth while I was trying to find a place to pull over yesterday. The clutch is seaming to operate correctly; it is releasing the rear wheels/brake drum from the rest of the transmission when the clutch pedal is depressed. I can crank the engine over while it's in neutral without any resistance or grinding. If I jack up a rear tire, I can spin the tire and the brake drum rotates without any binding or grinding. With one tire up of the floor, and the clutch engaged, I can crank the engine over and the rear wheel spins. I'm at a loss.

While it was being hoist up onto the flat bed, I had the brake lever in neutral, and you could hear snapping or knocking as whatever was binding up in there let go and then bound up again. But when we rolled it off the flatbed into the garage, it made no noises.

[jackdaron]

I vote for a triple gear shaft sheared.

[Will N]

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At first glance, the triple gears seem to be revolving correctly as I cranked the engine over. But I'll take a closer look. I'll bring each gear to the top one at a time, and check if there is any movement on the shaft. Thanks.

[ljbohlen]

Check the U Joint also. You may have sheared a pin or split the joint....
Doesn't sound like rear end because you can turn it without slippage as noted above.

Good luck.
Larry

[Will N]

Jack, I pried on all three triple gears, and they are firmly attached to the flywheel shafts.

Larry, could the U Joint have caused it to seem like it was locked in gear?

Thanks.

[yachtsmanbill]

You've got a cracked pinion gear / broken drive shaft at the nut end. The drive shaft Hyatt bearing may be the culprit too... ws

[Steve Jelf]

Bill is probably on the right track there. Because of the way sound travels in a T, folks often think they have a transmission or engine problem when the trouble is really in the rear end.

[Will N]

Bill, the car continued to move under the engine power. And now, if I jack up a rear wheel and spin it, the brake drum rotates. Would these things happen with a broken drive shaft or cracked pinion gear?

[yachtsmanbill]

Certainly! Its a "drag" connection at this point. Just enough. Run it up and down the drive way until it becomes a catastrophic failure. The rear end will need to come out, so anything south of he U joint will become evident. You need to do that to inspect for thrust washer failure anyways. Save the motor job for last, unless a fractured trans drum is evident. It could even be a broken crank to flywheel fracture. Most noisy trans issues are rear end related tho... ws

[Will N]

Bill, Thanks for your advice and expertise! I guess I could have mistaken the fact that it wouldn't stop when I stepped on the brake or reverse pedal, nor did it seem to go into low range when I stepped on the clutch, for it being stuck in high gear, when really, it was just rolling on it's own momentum with there being no firm connection between the tranny and rear end.

I know what I'm doing this off season!

[redmodelt]

could be something like this;
http://www.mtfca.com/discus/messages...tml?1378803229

[Will N]

I had someone come over and step on the brake pedal, with the tranny in neutral. I tried turning the one wheel I jacked up, and I could not turn the wheel while the brake was on. I'm thinking that this indicates that the driveshaft is not broken. But when we let the brake off, there was something binding, as the wheel would not initially turn, but after wiggling it back and forth, it began to turn, and we heard a knocking noise. Sounded like it might have been coming from around the Ujoint. I'll be pulling the rear end as soon as I have some time.

[Tom RSA]

This happened to my 1914 last year. Stepped on the brake, followed by horrific grinding and knocking sounds.The car would not stop or engage low or top gear, reverse had no effect and ran for 300 meters before stopping! I could then start the engine in neutral without any noise until a gear was selected and the noise returned. I suspected differential problems, but discovered the problem when I removed the hogs head.

[Will N]

Tom, What was it that you found when you removed the hogshead?

[yachtsmanbill]

The rivets failed that attach the pressure plate to the clutch spring/#4 main bearing guide.

[Tom RSA]

Yes, the rivets had failed. It was not apparent until I removed the hogshead. The whole assembly simply fell back into place under the spring pressure and the support of the 4th bearing guide when nothing was rotating.

[Buster]

I had a very similar thing happen to me in my '25 Hack. It ended up being a magnet that had come loose. Time to pull the engine.