Hello Everyone! Last October, I bought a fully rebuilt transmission for my 1949 Chevy business coupe (Chevs of the Forties $ 750 plus core) because the old one made so much racket in 3rd gear I couldn't stand it. I had to wait a while to get someone to install it (and also replace the clutch, pressure plate, throw-out bearing, u-joint, transmission mount, and drive shaft bearings) since I wanted to fix all the possible problems at one time. A local Chevy dealer did all the installation work in March. I picked up the car to drive home and at the first stoplight, it died and was towed home. I just this week got a new battery, starter, solenoid, and voltage regulator. It now starts fine but on the road it still makes the exact same racket in third gear. I checked the 90 weight oil and it has the transmission has the prescribed 1 1/2 pints in it. I am not sure if Chevs of the Forties sold me a lemon or ?. The sound is a loud clickety-clack noise but only in 3rd gear (stops when depressing clutch) and unfortunately is exactly the noise problem I was trying to solve and now is just the same as before with a rebuilt transmission. Feeling somewhat stupid after spending all this money, before I contact Chevs of the Forties and the Chevy dealer was wondering if anyone else has had this or a similar experience. Just as info, the original 216 was replaced with a 54 235 about 10 years ago and it still sounds and runs great (except in 3rd gear, of course). Could there be anything else wrong? Any ideas?
What is confusing me is that the noise is only in 3rd gear (direct drive). I would think that if it was the flywheel or clutch or u-joint it would happen in all gears.
I have no idea whether this applies to your issue but I put a new shift knob on my 38 to replace the original knob that was splitting. The new knob was a custom creation by a fellow on stovebolt.com and had a metal insert in the center. A very attractive knob. As it turns out the metal insert acted as a speaker and magnified all vibrations coming from the transmission. It sounded like my transmission was falling apart. I removed the pretty knob and replaced it with a hard rubber reproduction knob that mimics the original and all is well. If you've recently replaced your knob maybe it's the same issue???
VCCA Member 43216 Save a life, adopt a senior shelter pet. 1938 HB Business Coupe 1953 210 Sedan
Owing to the noise (Clicky-Clack) going away when the clutch is depressed, then it seems the clutch release bearing may be out of adjustment, riding loosely on the clutch cover's spring and doing the clacking, Only thing is that doesn't explain is it not doing so in first, reverse or second gears. Hmmm. You present an interesting mystory here.
May because the car is not in first or second long enough for you to notice the clack, it really is the clutch release bearing. I suggest you check the adjustment of the clutch pedal to see if the bearing is fully released as you drive along in drive gear.
Have you checked to see if your mother-in-law is not hidden under a blanket in the back seat? They are known to be annoying and, yes, some do make a clickity-clacking noise.
I hope that when you find the source of the annoying noise, you will let us know what in the world it was. You have us all scratching our heads "out here in radio land."
Best,
Charlie
BTW: Having made many costly mistakes by jumping to conclusions from a distance and enlisting someone whose opinion I respect, I would say you knee jerked (as I have from time to time) and spent a heap of money and still have the problem. There may be a lesson here. Not ragging you, but just saying. You know.
Perhaps the most difficult part of troubleshooting is defining the conditions that create problem.
I like Charlie’s idea that perhaps the condition exists in 1st and 2nd. You don’t hear it because you are only in those gears a short time and typically are accelerating. That loads the drive train in one direction.
As a test, drive the car for extended time in each gear. Accelerate, hold a steady speed, let off, and then re-accelerate. You ought be surprised what you hear.
I would try Rustys suggestion and if that fails to identify the problem I would next put the car up on stands and disconnect at the ujoint and then run thru the gears. In first and second the power is transmitted thru the counter shaft with no inline pressure at the mainshaft. In third the power is direct thru and it is possible the source of the noise is from the rear .