Petes75Vette

Ok, so you folks have been TREMENDOUS help with me slowly fixing the Vette. I've fixed one issue after another either through searching here or posting threads.

I'm down to 2 noise issues I need help figuring out.

- The first is coming from my engine bay, near the belts. It seems to be a tisk, tisk, tisk, slapping noise. It's especially noticable at idle. When you give it some gas, the noise settles down/goes away.

I'm thinking it could be a loose belt that's "slapping", but...when the car is off, all the belts seem nice and tight. This problem has been going on since I bought the car in February. Any thoughts?

- The second problem is a new problem that arrived after driving the car this past Sunday (drove it only very little). There seems to be a weird, loud wobble noise from the right rearish side of the car. At first I thought it was a flat tire, but after inspecting the tire and all parts in and under the rear of the car, everything looks totally fine.

I had someone stand outside and watch/listen as I drove by on the street. Everything looks to be fine, except there is definitely a noise. The wobble seems faster and lounder as you speed up, and then slows/is less noisy as you slow down. Where should I start to look??

Any help is again MUCH appreciated.

Peterbuilt

The rear: Does your parking break work?
Or do you have stock chrome trim on the wheels, sometimes they make noise.

toddalin

Do you have headers? The tisk, tisk, tisk could be a leak at the header gasket. This is especially prevelent on the #1 cylinder if you have a header-mount alternator because the bolt typically doesn't go in as far due to the mount.

Petes75Vette

Forgot to mention. It's a 1975 automatic.

The parking brake does not work. The wheels are not stock.

The parking brake has not worked since I got the car as far as I can tell, but to be honest I don't know if I remember noticing if it worked or not. The noise just started Sunday.

Petes75Vette

Yes, Hooker headers. The noise is very much by the alternator. Is this something that can be fixed, or do I just live with it (assuming that's the issue)?

PeteZO6

Try removing the alternator belt and start the engine. Noise goes away, it's the belt or the alternator, or alt. pulley. Or try removing other belts that you may have, and retest.

Have you jacked the rr wheel off the ground and then, holding the tire at 12 and 6 o'clock, try rocking the wheel in and out. Then do the same at 6 and 9 o'clock. Any looseness would mean the wheel bearing is shot.


Pete

Petes75Vette

I have tried the test pulling on the wheel...no movement at all. Very solid.

toddalin

Try tightening the header bolts, especially those on the cylinder that holds the alternator mount, and see if it goes away or lessens. This is real common.

I've used longer bolts in these positions but I ground them a bit shorter because you don't want them to bottom out in their holes. Also, if the bolts are too long and bottomed out, it can cause the tisk, tisk, tisk and tightening can make it worse.

You can buy "locking header bolts" to alleviate the problem of retightening them every now and then.

blue427

your timing chain could be worn,it'll slap the cover at an idle and the noise will go away as engine rpm's increase.

Petes75Vette

Thanks for the tips folks. Keep em' coming!!

For the rear wheel noise...do these pics show anything out of place/worn that I'm missing?

Petes75Vette

UPDATE:

Still no wobble in the tires. So I think the bearing is ok. I was looking for differences between the left and right wheels as the sound seems to be coming from the right, hoping find the difference and that be my issue.

I've found that with the car on stands and in Netural, I can spin the left tire no problem, round and round. The right tire (the side with noise) however, only goes about 1 rotation around and gets stuck. It won't go forward anymore. I can spin it backwards again about 1 rotation and it gets stuck again. Could this be an issue with the parking brake in back maybe? Haven't been able yet to figure out whats keeping the car in the small rotation.

However, maybe whatever it is, is what's causing the wobble sound. Obviously with the car in drive its able to make it around due to the force, but when it gets past the sticking point...maybe that's the noise occurring.

69 Chevy

In my experience it's better to elevate the rear by placing the jack stands under the outer part of the leaf spring. The half shaft U joints might be binding with the suspension hanging down like in your pic.

Could the E-brake cable be rubbing on those wide tires? I have mine pulled away with coil springs.

Petes75Vette

Thank you for the tip.