The Stovebolt Site Forums The Shop Area Engine Shop 235 squeek at low rpm

Was running the engine at idle, and I noticed a squeak at low rpm. I went and check the oil pressure and it read 0, so i shut it off hoping i didnt damage anything.

Is it safe to assume I need to replace the oil pump?

TIA

You can use a big screw driver or a hose to your ear like a stethoscope to locate the source of the squeak. Most common squeak for me has been the water pump, if so give her a shot of WD and see if it disappears. Best of luck.

i removed the belt to check and see if it was the water pump. Sound did not change.

Didnt want to run it any longer than that.

I agree with JiMerit's water pump speculation (fan belt, even, depending on the sound of the "squeak").

I'd be careful running the engine.
The 0 oil pressure is big a concern.
I'd disconnect the oil-pressure gauge sender-line at the block, and crank the engine (or, VERY briefly run the engine) to see if oil spurts out the block.
This does not assure oil flow throughout the block, but it says the oil pump is at least minimally OK.

Maybe someone has a safe "quick-check" oil-flow suggestion?

Has the engine had good oil pressure up to now?
I recently worked on a 235 that broke the spring in the relief valve in the oil pump, resulting in 0 oil pressure.

Here's my personal experience with squeaks at low rpm: they can become squeals rather quickly with your engine's symptoms. Been there...

I am an advocate of only turning the engine over by hand once the belt is found out to not be the culprit squeak maker.

Brad

Yeah it has had pressure up til now.

Also, the squeak goes away if i rev to a higher RPM

Did the Dizzy come out for any reason? Easy to miss the oil pump drive when it goes back in. A non-destructive test for 0 oil pressure, Pull the distributor(dizzy for short) and drive the pump with a drill. Adapters are at most FLAPS. Have some one watch the pressure gauge in the cab. If the drill makes pressure, then the pump is working. You will be able to feel the pump load the drill, that means it is working as well. If no pressure and no load..pull the pan and get close and personal with the pump and bottom end. If the pump is working. Then find out why it is not turning when the engine is running. There are reasons for no oil pressure. Some are mostly bad..and some are simple. Test the pump first. Only turn the engine by hand until you find the problem.

Forgot to add: Look at the drive gear on the dizzy. Should be pinned to the shaft. The cam gear can be seen with the Dizzy out. Shine a light into the hole and look. The cam drives the Dizzy. The dizzy drives the pump.

Steve, so how would the motor run if the gear was slipping?

zero oil pressure is a serious thing.Don't start the engine!!. Test the oil pump as Steve H suggests.Take the valve cover off so you can see if oil is coming to the head,while spinning the pump.