weird grinding sound...ka24de
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Hackysac300zx
- Posts: 67
- Joined: Fri Aug 02, 2013 10:03 pm
- Car: 93 Nissan 300zx 2+2 N/A (TT motor in the works)
93 Nissan 240sx Vert (restoration in progress)
weird grinding sound...ka24de
Hey all, i recently picked up a 93 vert w/ a ka24de for steal! well after some basic maintenance(oil change, plugs, plug wires, radiator flush, ect.) I noticed a grind...like metal on metal almost like when brake pads wear past the squealers...anyway here is a vid if anybody has some ideas...sounds like its coming from the pulleys possibly???
Re: weird grinding sound...ka24de
Any way you could try to pinpoint a better idea of where the sound is coming from? Some times some vacuum hose in your ear with the other end as a "stethoscope", sort of, can help listen for stuff. You say it's sqeaky? The video kind of makes it sound like a tap/scrub. I think we're missing out on the high frequency sounds.
What does it do when you rev the engine slightly? Take another video if you think it may offer more evidence
I'm not sure how you would touch much of the rotating assembly with what you've done. It sounds like the noise is 1:1 with engine speed - one of the reasons I want to hear the RPMs change some. At 800 RPM idle that would be ~13 revolutions per second, which is what this sounds like. So, one tap/squeak/scrub per revolution. That rules out front pulleys/fans - minus the crank pulley of course.
I had a quick thought of maybe something falling into one of your cylinders while you were changing plugs. Unlikely, but it would have the same kind of rhythm as that noise.
Dust cover maybe? Check around underneath the car and listen for it down there. Try to get a better idea of where the noise is coming from. That will help out a bit
What does it do when you rev the engine slightly? Take another video if you think it may offer more evidence
I'm not sure how you would touch much of the rotating assembly with what you've done. It sounds like the noise is 1:1 with engine speed - one of the reasons I want to hear the RPMs change some. At 800 RPM idle that would be ~13 revolutions per second, which is what this sounds like. So, one tap/squeak/scrub per revolution. That rules out front pulleys/fans - minus the crank pulley of course.
I had a quick thought of maybe something falling into one of your cylinders while you were changing plugs. Unlikely, but it would have the same kind of rhythm as that noise.
Dust cover maybe? Check around underneath the car and listen for it down there. Try to get a better idea of where the noise is coming from. That will help out a bit