SharkSkin

Be sure to rinse down the cooling fans with a good quality prop wash -- I'm sure Stan can tell you where to get it. Check the fetzer valve WYAIT.

dr bob

Ron, more funny noises from the list than from your car. Count yourself lucky!

perrys4

^^ isn't that always the case? lol

SharkSkin

Any update?

perrys4

Started the car yesterday and no noise. Didn't take long though for me to start hearing it, well before it got to temp. I am taking it to see Greg Wednesday to figure it out.

dr bob

Ron--

While under my car for the rear wheel bearing replace, I had the rear muffler off and the center section loose in the rear. During reinstall, I decided to bang on the pipes a bit to see if I could find the source of a weird 1200RPM twangy rattle I have. Sure enough, a smack with the rawhide mallet was enough to cause the rattle. Turned out to be a broken crossbrace between the two catalyst cans. Tiny crack in it, and would rattle when the engine is cold. Pulled on it a bit to add some clearance clarence, and it's good to go until I can get it to a muffler place to get it rewelded I guess. Or replace the cats.

Age, mileage, stresses and strains of normal use will cause things to adjust themselves, fracture from thermal or mechanical fatigue (really the same thing...), and sometimes just plain wear out. On the way they can make some funny noises. Don't be afraid to put the car up high on four stands, and run it while you roll around underneath with the stethoscope. Make sure the garage door is open though.

For those playing along at home, it was over 80º today. Got the garage warmed up good, washed the skylights on the house and the other upstairs windows. Like an early spring!

perrys4

Dropped by Precision today and had Greg and his trusty sidekick take a look at my car for this knocking noise. I could tell right away by Gregs expression this was something odd, something not unusual for my car.

Greg put it on the lift and it was hard to tell where the noise was coming from. By scoping it it seemed to be loudest at the rear of the torque tube, but greg said the knocking noise I am getting is not the typical noise heard when the bearings fail. They made sure all connections were tight and checked everythig over really well.

Consensus was to let it go unit something more definitive happens, Knocking can be heard from loudly with the window down and it changes, sometimes quiet or non-existant or very noisy. It's another mystery with the Perry car, lol. Maybe Greg will chime in and fill in any details I have missed. When I find out what it is I will update this thread again. Thanks for all of the input.

Jim bailey - 928 International

The cast iron weight (vibration absorber) inside the tube MIGHT have shifted and moved out of the rubber band mounts. When they slide rear ward they can hit the input shaft to the trans.

GregBBRD

Could be. It is certainly not a "normal" failure mode thing...I've never heard anything like it....and I'm going to guess that I've been under more than the "normal" guy. There's no doubt that it is in the very back of the torque tube area and it is a solid mechanical clunking noise. Not a rattle, not a vibration. This is a clunk

Ron....go out and hit the brakes really hard and see if the noise changes. Perhaps the vibration absorber is loose and you can move it back forward.

Rob Edwards

If the weight has broken out of its mounts could you take a big *** magnet and slide the weight back and forth? Not that it would cure anything but at least you'd know. Or maybe you can poke it/move it with a coat hanger thru the rear pinch bolt hole?

perrys4

Thats how you said to fix low oil level issue, LOL!! Honestly, I am not sure if you are serious or not. It was really quiet by the time I got home. Thanks again Greg.

SharkSkin

Did you check the pinch bolt? If not, that's a possiblity, it could be thunking around back there. Also the flexplate bolts. I'd be surprised if Greg didn't give them a look, since they are so easy to check.

I thought the iron weight was between the middle and rear bearing carriers. Wouldn't it just push the rear bearing up against the pinch collar?

Mrmerlin

yes the damper will hammer the bearing supports on either side of it, it is most noticeable when coming to a fast stop you will just come to a stop and feel a slight thud from the driveline

Jim bailey - 928 International

The automatic has the weight at the rear , the 5 speed has it between the middle and rear bearing carrier if it has one at all ...

SharkSkin

Thanks for clarifying, Jim.