Clutch/Tranny Noise

[Nismo37]

Hey Guys,

I just drove 240Z home 600 miles last weekend and she ran like a top. Now that I've gotten to know the car a little bit more I've noticed that clutch slips a little in 1st gear when starting from a stop. In the past couple of days there is a loud chatter/bang that comes from the transmission or clutch when I'm idling. The noise mostly goes away when I depress the clutch or get the RPM's up a fair amount. Any ideas?

[Mikes Z car]

Meridian, Idaho ???!!?? That is less than 15 miles from me. I'd rather not guess on your noise though.

Do you idle with the clutch pedal depressed or do you idle by putting the transmission in neutral and leaving the clutch pedal alone?

Does the noise repeat at regular intervals like something is spinning and hitting somethng else?

Edited May 25, 2014 by Mikes Z car

[Nismo37]

I typically idle in neutral and leave the clutch pedal alone. The noise does repeat at regular intervals and it sounds like it's hitting something. It just recently started making the noise.

[Nismo37]

By the way. Since you're close by. Are you a member of the ZCCI (Z Car Club of Idaho)? Do they get together at all anymore?

[Mikes Z car]

I am not a member of any local clubs. I looked into them a few years ago though it seemed they were inactive. I am not aware that any of them get together any more.

What year is your car?

[Nismo37]

It's an early 1971. Build date of 11/70. I've tried getting involved but I've also found them to be pretty inactive.

[Mikes Z car]

I keep hoping someone will see your thread and share something with you on the likely source of your noise but I would say a likely culprit would be the throwout bearing. If the noise continues I would think pulling the transmission would be in order. I did that on the 71 240Z (build date 8/71) I had 30 years ago not that that means I could do it again without help. When I did it I left the engine in the car. The throwout bearing looks like a small metal doughnut with bearings so one face can turn while the other remains stationary though I am having trouble visualizing a failure mode that would cause what you are hearing. Maybe the bolts have worked loose on the clutch itself?

Edited May 25, 2014 by Mikes Z car

[bartsscooterservice]

Hey Guys,

I just drove 240Z home 600 miles last weekend and she ran like a top. Now that I've gotten to know the car a little bit more I've noticed that clutch slips a little in 1st gear when starting from a stop. In the past couple of days there is a loud chatter/bang that comes from the transmission or clutch when I'm idling. The noise mostly goes away when I depress the clutch or get the RPM's up a fair amount. Any ideas?

It's old...you have to take off the transmission to find the problem.

[Pop's Z]

If you are slipping in 1st you might as well bite the bullet and replace the pressure plate, clutch disc, pilot bearing, and the throw-out bearing. As long as you're at it replace the front seal on the tranny, too. I've done the trans both ways and IMHO it's a bit easier to take the engine/trans out as a unit especially when lining up the trans shaft with the flywheel. Oh and have the face of the flywheel machined smooth. Do it all at once and don't worry about it again. Just my 2 cents as I've been there, done that...no t-shirt, though.

Cheers, Mike

[siteunseen]

If it goes away when you push in the clutch it's the throw out bearing. I agree with above, do it all and don't worry again.

[Diseazd]

If you are slipping in 1st you might as well bite the bullet and replace the pressure plate' date=' clutch disc, pilot bearing, and the throw-out bearing. As long as you're at it replace the front seal on the tranny, too. I've done the trans both ways and IMHO it's a bit easier to take the engine/trans out as a unit especially when lining up the trans shaft with the flywheel. Oh and have the face of the flywheel machined smooth. Do it all at once and don't worry about it again. Just my 2 cents as I've been there, done that...no t-shirt, though.

Cheers, Mike[/quote']

.......and the crank seal and the slave cylinder.

[Zed Head]

The noise mostly goes away when I depress the clutch or get the RPM's up a fair amount. Any ideas?

A common noise for the Nissan transmissions is the countershaft bearing. When you disengage the engine from the transmission by pressing the clutch pedal, the bearing stops spinning. The banging could be a bearing with some balls missing. You might want to get in there before it fails completely. It's under the transmission front cover so you'll be able to get to it easily once the transmission is out.