: noise from my 500



circlewfarmsinc
09-07-04, 04:32 PM
Hey guys,

I've had my car for a couple months now and I have a noise coming from the engine that seems to be getting louder. The car has digital gages and the oil pressure gage was not functioning when I bought the car. I installed a mechanical gage this weekend and have 40-45 psi oil pressure at idle with the engine at 200 degrees. So it does not appear to have an oil pressure problem. I do not know the specs on any of the internal engine parts, but the engine has a loping idle. It seems non stock, but not too radical. The noise is like someone tapping a tin can down inside the engine. When we first noticed the noise it seemed to only do it when it is cold, but lately I hear it all the time, even when the engine is hot. I removed the valve covers and the noise was somewhat less, but I cannot tell the the rocker arms are hitting anything. The rocker arms appear to be stock. I did notice that there is not much oil coming from the pushrods at idle. My dad says it does not sound like a rod knocking to him, and the car is still very snappy. Is there anything else that I should check? Dad says he has seen loose pulleys make this noise before, so I took the alt belt off and loosened the ps belt but it did not make any difference. The crank pulley is tight. While looking around the engine I have noticed that the crank pulley is very close to the water pump. I could get a piece of paper between them, but there is not much more clearance than that. This engine has what appears to be a big cast iron pulley on the crank. Any suggestions will be appreciated.

Thanks,
Dwayne

JTraik
09-07-04, 08:38 PM
Lifter tick or no? That belt should be pretty close to the pump, i know what your talking about. What year is the car?

lux hauler
09-07-04, 10:11 PM
Leaking exhaust manifold.....?

JTraik
09-07-04, 10:46 PM
Ehh... an exhaust tick wouldnt be intermittent like that though.

circlewfarmsinc
09-08-04, 11:09 AM
This engine is in a 53 Studebaker... I do have a slight exhaust leak, but I don't think it is the same sound? I guess I will try and fix that and see...
When the engine is first started cold there is a little lifter tick, but it goes away fairly quickly and the monkey beating the tin can is still there! It will take me a few days to get the exhaust fixed and I'll post the results. This engine has only 900 miles on it since a complete rebuild, is the lifter tick something I will have to live with on a Cadillac at cold start, or has something been assembled wrong? I've read on several other post about people haveing lifters ticking, but oil pressure seems to be the only concern and I have checked that? Thanks for your help!

Dwayne

circlewfarmsinc
09-24-04, 11:10 PM
Okay! Do I have something interesting to tell! I fixed the exhaust leak (previous owner installed wrong collector gaskets). Earlier I had noticed the noise stopped with the pass side valve cover removed (remember this)...
So I ordered up a set of bulldog covers thinking that maybe the short cheap chrome covers we hitting a rocker arm with the higher lift cam. I got the bulldogs on this afternoon, hit the starter and the ticking had become knocking (very loud). So I said to myself, self, that has to be a rocker arm hitting the thicker aluminum covers. But there was no tell tell marks inside the covers. I removed the covers and fired the engine, no noise. Smooth and quiet. I reinstalled the driver side cover and fired the engine, smooth and quiet. I reinstalled the pass side without tightening the bolts and cranked the engine, smooth and quiet. I moved the cover around as much as it would let me with the bolts started and I could not make it tick, but I noticed that there was a lot of suction on the cover. As soon as the corner bolts were tightened the tick would return. I removed the cover twice to grind away at the inside corners for clearance, but the tick returned as soon as the bolts were tightened. I was wondering about the high suction on the cover as I have never seen such, so I removed the vacuum line from the PCV valve. And guess what, the ticking went away? At the same time, I was using a new billett specialties breather and PCV valve. I removed the breather from the pass cover and hooked the PCV back and the noise did not return. The breather had about four small maybe 1/16 holes for air in a baffle, so I drilled a 3/8" hole thru the baffle and reinstalled. The noise was gone. Can anyone explain this? How did the high suction make the ticking sound? I am using a port at the bottom front of the Edelbrock 700 cfm carb for the PCV. Is the carb too small, causing this high vacuum? The previous owner said it is a 700? Surely one of you experienced Cadillac guys have encounted this before, or is my engine just a SOB...