The Stovebolt Site Forums The Shop Area Driveline 1941 Chev Truck Shifting Issues

Hello all,

My brother and I are resurrecting a 1941 Chevrolet 1/2 ton, with a rebuilt 235 (not 216) new clutch, and stock original 4 speed non-synchro transmission. With the engine idling at roughly 600 rpm, we are experiencing lots of gear clashing and crunching when shifting into either first or second with the clutch pedal pressed in. We have not been able to engage a gear, or at least we're reluctant to muscle into gear with all the clashing we're experiencing.

We have pretty much confirmed it's not an issue with the clutch, it's new and when the pedal is depressed there is clearance between the clutch face and flywheel. When the pedal is released the clutch contacts the flywheel.

When the transmission was out, we did a visual inspection of the gears with the top cover off and all gears appeared to be in good shape with no visible tooth chips, etc. We did not tear down the transmission, but mostly cleaned it out and replaced fluid. It seemed to be spinning without any binding or weirdness, so we didn't disassemble it. We think we had the shifter and cover installed correctly, as it seemed to shift through all 4 forward speeds and reverse.

Is it possible to install the shifter and cover incorrectly, so that it seems to be shifting gears correctly while the engine is not running, but shifting is not correct when the engine is running?

Is it likely we moved gears in the case to check out their condition, but they were never removed or disassembled by my brother or myself.. Is it possible the gears have to be in a certain arrangment when the cover/shifter goes back on? We believe we had the shifter forks in the correct position on the mainshaft.

Any suggestion or experience anyone has with this time of transmission would be appreciated. We really hope that we don't have to take this heavy piece of pig iron out again. Thanks...

How is the pilot bushing/bearing in the flywheel? If that's binding up the result will be the same as the clutch disc dragging.

Thanks for replying Kevin. We replaced the pilot bushing, and I have had experience in setting bronze pilot bushings, so I don't think the problem is there.

If it grinds when putting it in gear, that means the gears are still turning.
Not a transmission problem, but a clutch problem.
How much free play do you have on your clutch pedal?

You may want to try starting it in gear, with the back end off the ground.
You can then put the brakes on and see then if the clutch will disengage at all.
You may have the disc in backwards.

Ditto on the backwards disc. The springs in the hub of the disc stick out further on one side than the other, and if they are installed with the springs toward the flywheel they will drag on the flywheel to crankshaft bolt heads and cause the disc to keep spinning even with the clutch pedal depressed. Hold the clutch pedal down, put the trans into gear, and then start the engine. If the springs are dragging, they will make grinding noise as they touch the bolt heads. The thicker portion of the disc hub is supposed to protrude into the pressure plate- - - -not face the flywheel. Most replacement discs have either a paper label or a stamping that says "flywheel side".
Jerry

I will check the possibility of a backwards disk, but I don't think that's the problem. I have installed a good number of clutch disks, and pretty much know which way they go and always check any labels/instructions attached to parts. The possiblity of disk drag is a good thing to check. however. I did adjust the "eye hook" bolt so that the pedal has about 3/4" to 1 inch free travel, like the book says, but it could be dragging enough to cause engagement issues when the pedal is depressed. Thanks for the suggestions.

It was clutch drag.

New clutch, new pressure plate, new throwout bearing, new pilot bushing, not adjusted enough!

It turned out that the eye bolt that had to be adjusted with the nut all the way in. Now it engages properly.

Weird about the hardware. It's a shouldered eyebolt, original GM issue. Did GM just go to a hardware store to pick up some of its "specialized" parts way back then? I can see closing up the inner aperture of the eyebolt hole would take up some of the free play in the clutch pedal. The shop manual spec of 3/4" to 1" freeplay is excessive, at least in this case. There is still freeplay in the clutch pedal (just not as much) but enough so that the throwout bearing is not spinning when the clutch pedal is off.

I thank those who responded to my post.....Charles Evans

I think you will find that after a little use, you will be able to get adjust it to factory specs. Some of the high spots on the new disc need to be worn down.

When I replaced the clutch in mine, I had to tighten the eye and bush the other linkage ends in order to take up the wear, I have to have the peddle ALMOST at the floor to disengage but that's what the shop manual calls for.