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Gear train noise - Magard - 06-01-2019
I been having a slight noise in front end of engine. Almost sounds like a belt maybe but I’m thinking it might oil pump. It’s coming from the bottom of engine somewhere around the balancer.
Seems a little worse when compressor is engaged hard to tell. I been reading on past posts about oil pump not being shimmed properly. Could a pump gear rattle a little even if it’s under pressure pumping oil? Also when you open the fill tube when running you can’t hear anything unusual coming from the fill tube. It’s a 2250 that I just In framed about 30k miles ago. I guess I’m pulling the pan tomorrow.
RE: Gear train noise - Waterloo - 06-01-2019
I don't know if there are any scissor gears in there, I had one on my Injector cam that was ready to blow apart. There are tensioner springs with bolts that were loose and warn. I could never hear them though, but they had rubbed through over half of the spring retaining bolts. It was a disaster waiting to happen. We replaced with a solid gear, which was ridiculous $$$$ I want to say close to $500. I know in my 871 there is another scissor gear in that lower housing down towards the damper.
The oil pump, if I remember correctly, did not have that much if any play in the gearing, certainly not enough to be heard. I can't think of anything else down there. Unless, like your thinking a bad shim on the pump. I left mine stock.
RE: Gear train noise - Rawze - 06-01-2019
if it is a medium pitch sounding sort of steady gear whine that goes up and down in pitch with engine rpm, almost always, it is the oil pump going out. - I can hear that distinct sound from across a parking lot at the truck stops on every truck that has a weak or failing oil pump, it is very common.
The point where you replace it, is when it is just about half as loud( or louder ) than the engine at 100 feet away or so.
RE: Gear train noise - Magard - 06-01-2019
The truck has a gear wine. It has always had that. This is more of a rattling sound... I’m gonna pull the fan belt and then run it a minute and see if I still hear it.
RE: Gear train noise - rrod - 06-01-2019
(06-01-2019 )Magard Wrote: The truck has a gear wine. It has always had that.I’m curious if you know why is that.
RE: Gear train noise - Magard - 06-01-2019
More like a moaning ringing sound. I thought it was pretty normal. Just inframed it didn’t see anything abnormal. I had a 570 isx. Pre emissions. It made that same sound but even more pronounced. Rawze tells me it’s probably not the oil pump from the description. I’m gonna change oil and cut open filter. Will see.