Transmission squeak/grinding noise

[Spades]

I have been collecting parts to swap out my naps z20 four speed for a 240sx five speed, and I think I may need to start the project sooner than later. I thought I had a rattle from my exhaust at first because I had an intermittent rattle/squeak/grinding sound, but when I went to investigate, the noise wasn't from the exhaust, it was from the clutch area of the transmission.

 

I drove the car for a few more days and the noise became worse and worse, and since I was laid off a few months ago, I parked the car until I could investigate further. Now I may have finally found work and have my tax refund, so I have the money to begin repairs, and will need to have a working car again. Before I begin ripping out the transmission, I wanted to get some opinions on if I am barking up the right tree, my experience with transmissions is limited.

 

The noise is there if the clutch is in or out, but is worse in neutral idling and in cold weather. I am guessing that is a main shaft bearing or throw out bearing. I think the throw out bearing noise goes away when the clutch is pressed or released though, but again, my knowledge here is limited.

 

I just want to make sure I am barking up the right tree and that this noise is transmission related. Thanks in advance for the help!

[Bullet_theory]

I have been collecting parts to swap out my naps z20 four speed for a 240sx five speed, and I think I may need to start the project sooner than later. I thought I had a rattle from my exhaust at first because I had an intermittent rattle/squeak/grinding sound, but when I went to investigate, the noise wasn't from the exhaust, it was from the clutch area of the transmission.

 

I drove the car for a few more days and the noise became worse and worse, and since I was laid off a few months ago, I parked the car until I could investigate further. Now I may have finally found work and have my tax refund, so I have the money to begin repairs, and will need to have a working car again. Before I begin ripping out the transmission, I wanted to get some opinions on if I am barking up the right tree, my experience with transmissions is limited.

 

The noise is there if the clutch is in or out, but is worse in neutral idling and in cold weather. I am guessing that is a main shaft bearing or throw out bearing. I think the throw out bearing noise goes away when the clutch is pressed or released though, but again, my knowledge here is limited.

 

I just want to make sure I am barking up the right tree and that this noise is transmission related. Thanks in advance for the help!

 

ok what vehicle, with an 4 speed and a napz?.... that kindof make a bit of diff.... and ...please check the oil... make sure it has some... i say this because my neighbor just started his car up and it made a whirrrrrrrrRrrrrRrrrrRRrring noise.. no oil... but yes the throwout bearing isnt a constant sound... and i know on my l20 my motor would grind time from time because the starter bolts loosened up over the years ... check everything else out... think of it as a process of elimination, we cant hear it... but we can walk you thru it.... and datzenmike is like the king of the trans.. so im sure hell stop by soon

 

Edit: i just had something pop into mind, does it seem like the clutch has a really small throw out/engaging spot? like less then an inch? http://community.ratsun.net/topic/30161-another-clutchtrans-issue-after-motor-swap/

[datzenmike]

Hmm the throw out isn't spinning then the clutch is out, peddle up. (or shouldn't be)

 

I'd check the oil level first. If low I'd drain and inspect it. The drain plug may have a magnet on it that will collect ferrous metal. If you find metal flakes (or worse) then something has gone wrong inside. If it looks fine and you plan to drive it, refill and see if it's quieter. If it's full, changing the oil probably won't do much. Continue with the 5 speed swap.

 

The F4W63 uses small needle bearings front and back to support the counter gear. The main shaft has needle bearings in the back and a ball bearing in the front. Noise idling in neutral could be the front mainshaft ball bearing or one or both counter bearings. If it cooked it's cooked and you are swapping anyway.

[Spades]

I think I will continue collecting parts and put the 5 speed together, I just need to have the flywheel I picked up from a wrecking yard inspected and surfaced or buy a new flywheel, and buy a slave cylinder for it. I am assuming I will have to shorten the driveshaft, but I have the money to do that now, so I will just keep forging ahead with the swap.

 

I just wanted to make sure this sound was transmission related, and from my limited transmission experience, it is the sound of a input/main shaft bearing going out, because every other noise I know of gets worse or better when you engage or disengage the clutch(throw out or pilot bearing, ect).