[93LT1Bird]

Hi everybody, what does "Cam Static Noise" mean? I had a mechanic whose working on engine for us that said he heard some static noise from cam with a stethoscope. The engine is not out of any generation bird, but i didn't really know where to post.

Thanks for the help,
Gary

[Knightfire83]

Never heard of that reference before, but to me that would mean a noise that does not change.

A common lifter tick comes to mind....

Which in itself is kinda strange, because a noise with the camshaft should change with engine speed,
or at least the repetition of it.
This mechanic trustworthy? I could be completely wrong, but sounds like maybe he is trying to use unfamiliar references to confuse the cu$tomer. :waitasec:
Either that or he's really good at what he does. Trying to diagnose internal engine problems with a stethoscope is an art in itself.

Strange indeed..... Perhaps someone else has more insight.

Now I'm going to use my digital computational machine to read more electronically encoded information.

[93LT1Bird]

Well this situation was about my wife's jeep liberty, it overheated because water pump and fan assembly went out at same time. She ended up driving it home instead of pulling over and it blew a head gasket and warped the heads. We still had warranty covered on jeep, but never dealt with any warranty company. I wanted to just get rid of jeep cause i was stressed with all problems we've had but she and her dad insisted on using warranty. To make a long story short, warranty company in very, very, very, small print says "owners are responsible if overheats" so they are only covering certain parts on jeep. Mechanic is someone who we don't know, and has small business just down from road from us he was eager to help us and didn't have problem with the warranty company even though other business turn us down. Well he had heads shaved at machine shop, replaced all gaskets, and was testing engine for leaks. He tells us that he "heard static noise from cam with the stethoscope " and rather than messing up engine down the road in say 6 months, he wanted to have it fixed by having the cam "polished". I have never heard of cam being polished just heads ported and polished and that's to cut down resistance, right??

The mechanic is stressed with warranty company cause they are really nitpicking everything, i get the feeling he just wants the jeep out of his bay but insists that he wants this job done right. We have the total bill from before having to have cam sent to machine shop, and we asked him if price is going to change and how long before we get jeep back, but he is very careful about what he says. I understand it take some time to do this job, but we've been burned before by another mechanic and are just worried about this one too.

[Knightfire83]

I'm not Dr. Engine, but I haven't heard of polishing a camshaft prior to your post. I have been searching the net formulating an opinion. Now, polishing a crankshaft is common. The process is much like when you polish a paint job. It leaves the bearing contact surface of the shaft incredibly smooth, giving the area where the thin film of oil resides a excellent surface to ride on,extending the life of the bearings.

I imagine this has to be an overhead cam engine, for the cam to be an issue after overheating.

It all would depend on just how much if any the heads actually warped. On a good head the cam is mounted into the head, all the cam journals would be straight and inline with one another. If the head has warped, you could flatten out the head mating surface to the block with resurfacing. However the cam journals would still be warped and out of line with one another. This would require them to be align-bored to be perfectly lined up.

To do the job 100% correctly, the cam journals would have to be align-bored, cam polished or replaced, and new bearings installed.

What I'm not understanding is that if there is "static noise" coming from the camshaft that just polishing the camshaft would solve, wouldn't there be damage to the bearings or alignment issues to be causing the noise?

I would ask for a quote on exactly how much more money it would be for him to do what he wants to do. This is a good sized job. It could be that he didn't make enough off the warranty and is looking for profit or to break even.
Also I would ask if the cam journals were align-bored when the head was resurfaced or if he plans to replace the cam bearings.

What he wants to do certainly couldn't hurt the engine, all depends on how much $$ you are willing to spend. For a daily driver and not a high dollar performance engine, I would be tempted to run it as is.

What is really needed here is the opinion of someone who is a machinist or has experience rebuilding newer engines. But since no one else is posting this is my $0.02 of the situation.

[juggernaut]

He's scamming your insurance company. Polishing ANY part in the rotating assembly is mainly for tight tolerance, high horsepower engines. I'm a mechanic with 5 years of school and 8 years of training/experience, and I don't even know how exactly you would check a cam for "static noise". If there was a problem with any mating surface on the cam, I would imagine the lifters, valves, and timing chain would make way more noise, rendering any other noise inaudible. I don't really know what else to make of this.. So there's my opinion.

[93LT1Bird]

Formula4Disaster, on 06 February 2012 - 06:05 PM, said:

I just googled camshaft static noise and automotive camshaft static noise and I came up with a big ole goose egg.

thanks guys,

i had done a search but came up with almost nothing that i understood and wanted to get some expert advice. Well we have the bill of what work was done before this and the mechanic did not contact us about this issue before doing the work, so i told him that the bill that we have is what we are responsible for and no more. If he and machine shop failed to complete there work then they needed to hash that out between them and not try to pass the buck onto us. We are covering our bases with a lawyer friend that has dealt with situations like this. I will have to keep you guys updated with what goes on. This is why i hate dealing with mechanics, most of them seem to want to get over on you and end up giving decent mechanics a bad name.

thanks
Gary