Diagnosing valve train noise

[Jacquiles]

My 86 944 has been making some valve train noise for a while. I removed the cam tower a while ago and found two lifters that could be depressed when out of the car, so I replaced them with some used ones that were in good shape.

Only thing is it seems like the noise is still present. I just cleaned out my garage and I’m getting ready to do some diagnosing. I just wanted to see what I should look for as far as common valve train problems. It’s audible at all times but is more noticeable at specific rpm’s. May not be anything but I want to make sure.

I was going to upload a video, but the compression of the file makes it very hard to hear the sound

[Tom]

Try uploading it to Youtube and posting a link. I think you can upload an mp3 file too? If not, change the extension to pdf to trick the system... Is it the common lifter ticking sound, or something else? Sometimes changing weather and oil viscosity and cause ticking that comes and goes... Did you take a close look at the cam shaft for any damage there? If it is one or two lifters, you can usually home in on the loud ones with a mechanics stethoscope.

[Jacquiles]

Try uploading it to Youtube and posting a link. I think you can upload an mp3 file too? If not, change the extension to pdf to trick the system... Is it the common lifter ticking sound, or something else? Sometimes changing weather and oil viscosity and cause ticking that comes and goes... Did you take a close look at the cam shaft for any damage there? If it is one or two lifters, you can usually home in on the loud ones with a mechanics stethoscope.

Hey Tom, uploading to YouTube worked much better. Its hard to hear, but it’s a rhythmic clacking that can be heard best when I raise the rpm and hold it there.



I’m not sure if this is a common sound. I can hear it when I’m driving and I have the windows down. Especially if there is an object to the side of my car where the sound bounces off and makes it easier for me to hear inside the car.

I did not see any damage on the camshaft last time I had it apart when I replace two of the lifters. It a pretty substantial clacking sound. Not really a small tick. Sounds like the camshaft is slapping a lifter instead just a little tick

[blueline]

@Jacquiles

The YouTube video you posted is set to private.

[Jacquiles]

@Jacquiles

The YouTube video you posted is set to private.

Oof, try it now, I set it to public

[Tom]

Hmmm.... at least on my phone and computer, neither of which have great speakers, I can't hear anything out of the ordinary. Your balance shaft is a tad on the tight side. I don't hear any traditional lifter noise. Can you hear what you are concerned about in this video, as posted on youtube? Sometimes exhaust leaks and or belt slap can sounds like valve train noise...?

[walfreyydo]

Yeah I dont hear much of concern either. Second that the balance shaft belt is a tad tight (thats the slight whine sound that goes up in pitch with engine speed).

[Jacquiles]

Hmmm.... at least on my phone and computer, neither of which have great speakers, I can't hear anything out of the ordinary. Your balance shaft is a tad on the tight side. I don't hear any traditional lifter noise. Can you hear what you are concerned about in this video, as posted on youtube? Sometimes exhaust leaks and or belt slap can sounds like valve train noise...?

Yea I can hear it through the video, but it’s still hard to hear over video because the balance shaft whine is kinda loud. I’ll upload another video with the balance shaft belt off when I get done with work later this afternoon.

I also may be crazy, and it’s a normal sound, I just don’t want to break anything

[PSU_Crash]

Jacquiles I can hear it. Kind of a rhythmic clack clack .... clack clack .... Although I don't know what that might be.
Also just learned that apparently my balance belt is also a bit tight

[Jacquiles]

Hey I got the balance shaft belt and all the other belts other than timing removed and it’s much easier to hear.

This could be totally normal but I feel like there is an extra clacky sound. I just re watched the video, and when I hold it at a steady elevated rpm, you can hear it come and go. It sorta of fades in and then back out. If you were to set a metronome to it, you can hear it on the first and 3rd beat(out of 4). Kinda happens half of the time

If you go to the time mark 0:40, you can hear it very clearly at 0:44.