The Stovebolt Site Forums The Shop Area Driveline JH-1126 Transmission Guide Pins

Going to change the TO bearing on '54 3100 with 4 Speed transmission. What is the thread size of the J-1126 Guide pins? Plan on getting a bolt longe enough to slide transmission back on to get to TO Bearing. If necessary, I can remove a bolt out and make a pin. wanted to have it available when I pull the bolts out. thanks for any help.
frank

To make the pins, I cut the heads off two 1/2" NC bolts. One pin is 2 1/4" long and the other is 3 1/2" long.

Thanks. That will help.
Frank

I probably should ask one more question. Can I change the Pilot Bering by just sliding the Transmission aft on the guide pins. I do not need to lower and remove the rear axle. question is because of the closed drive shaft. Have a lot more experience with Model A and to remove the transmission you either remove the engine or drop and roll back the rearend. Thanks again for the help
frank

You won't be able to change the pilot bearing by just sliding the transmission back on guide pins (unless they're REALLY LONG! )
You'll need to use a slide hammer to pull the old pilot bearing out of the crankshaft, and the transmission will be in the way of that. You can remove the transmission by disconnecting the u-joint, and pivoting the torque tube up out of the way, and then pull the transmission back and out. It'll have to come back at least 8 inches or so (the length of the input shaft in front of the transmission case.) Then the clutch pressure plate will have to be removed. That will give you enough room to either use a slide hammer or the hydraulic method to remove the pilot bearing. The latter consists of stuffing the cavity of the pilot bearing full of bread, or grease, and driving a close fitting shaft into the pilot bearing. The hydraulic pressure will push the bushing out.

I apologize. i switched from the throw out bearing to the pilot bearing in the last reply. i think the throwout bearing is the problem not the pilot bearing. Can the throw out bearing be changed by sliding the transmission aft on the guide pins? Sorry i misled you.
Frank

Changing the throwout bearing is easier than the pilot bearing, but you'll still need to get the transmission nearly all the way out of the bellhousing. The pressure plate wouldn't have to be unbolted.
Also, the guide pins can't be that long because parts of the transmission case are in the way. Long guide pins wouldn't be able to be inserted in the bolt holes and threaded into the bellhousing.

There's an easy way to remove the pilot bushing. Just screw a 5/8" threading tap into the bushing after removing the transmission and clutch. When the tap bottoms out in the counterbore in the crankshaft, keep turning it. The bushing will walk out of the crankshaft as it follows the threads on the tap. Getting the new bushing installed can be somewhat of a challenge if the trans isn't completely removed, however.
Jerry

I probably should give you "the rest of the story".

I bought the truck assuming the previous owner was on the level with me. Had been Painted and seats recovered, both professional jobs. very nice. None of the mechanical work had been done. I started i got it running just to see where i was. Rebuild brakes completely, Rebuilt the front end and some other small mechanical things. Started to drive it and found issues in the engine. Transmission seemed to be ok. Took the engine to get it rebuilt and found it had a cracked block. Engine rebuilder put a "clutch Kit" in which I assumed was a throw out bearing and pilot bearing. After about 2000 miles started to notice a growl when clutch pedal is in. No noise when clutch is out. From that I have assumed it was the throw out bearing. when I first posted I by mistake said TO bearing, but in a later post i sail pilot bearing by mistake. that got everyone confused.

I wondered if the throw out bearing could be changed by the comment about the length of the guide pins.

Sounds like i need to plan on removing the transmission completely. I was hoping i could just move it aft for enough to change the throw out bearing.

What do you think of my thought about it being the throw-out bearing that is causing the growling? thanks for your help and suggestions.
Frank

Frank - I think for all intended purposes that your topic really belongs in the Driveline forum as it's not really engine related, so it's been moved to the correct forum for further discussion and help.

As to your question about replacing the existing throwout (TO) bearing, I'd suggest you disconnect and raise/brace your torque tube and pull the transmission back as suggested by klhansen above. You should have it fully supported, secured to a transmission jack or suspended using a hoist to prevent accidentally dropping it on yourself when trying to pull out the TO bearing. Safety First!

Thanks for the info.