I'm in process of doing a 350 swap and priming the engine after assembly. First time building an engine. But I'm getting this sound when priming that sounds to me like a pump grinding noise and not sure if its normal. Seems strange to me. I'd rather not get the engine into vehicle and then have an issue later so want to resolve now.

I've actually already swapped in a new M55 pump, and got the same noise. Its a brand new GM oil pan. I believe I have the pickup to pan clearance OK. I looked in there with an endoscope through the drain hole and did not see any interferences or pickup contact. Its much louder when there is oil in the pan, no oil in pan and its there but quieter. The pressure seems normal. I do have one of those oil pump driveshafts with the all metal collar instead of the plastic collar. Don't know what else it could be or what to check next (if it is not normal). Ignore the drill noise but like at 20 seconds when zoom into the pan can really hear what I'm referring to.

Please check out the video and appreciate any advice.

 

I don't hear anything thru the video but the drill. Do you have the valve covers off and verified oil coming out of each and every hole while rotating engine every so often? If so, sounds ok or maybe try another vid with a quieter drill? Sry

 

Yes I did check and I was getting oil through at each hole at the rockers.

Here another video. I guess I could drop the pan and turn the pump and try to locate it that way. Again, assuming its not normal though.

 

Hmm, it's hard to isolate the noise without being in the room I think. Do you get any resistance / grindy noise when you turn it with a screwdriver or speed wrench?

 

That's what mine sounded like when I primed it. It's mostly drill noise. Maybe I'm missing something in the audio but my drill got pretty warm and made a bit of noise.

 

Alright I'm still baffled with this and project stalled until can resolve.

Here's a video with a blanket over the drill, so the noise in the video is what I'm referring to. It cant be normal?

No idea what this would be or where to start checking next..

With no oil the noise is not there - but when oil is added its quite loud.

 

I've listened to them all and do not hear anything abnormal, I would prime it right before you are ready to turn it over, then fire it up. If you are hearing something we don't, then by all means investigate it, but from what I hear in these videos sounds totally normal on primes I have done. Just make sure you have oil coming out where it is supposed to, and not anywhere it isn't and you should be fine.

 

Thanks for sharing this video.

 

I believe I may have finally solved it. After more tries with same results broke down and bought a shark tooth pump to see if it would improve. In the box has instructions that the cover should be torqued to 80-106 in-lbs. Well immediately I thought I must have over torqued mine before. No videos or anywhere had mentioned the torque on the pump cover and somehow it had not even crossed my mind. So I put this one in after torquing properly and its much much quieter. Still a bit of noise if you put your head next to the pan, but overall fairly quiet.

Unrelated question, my engine was upside down on the stand for a while now during troubleshooting, and I just noticed that its clear that oil seeped past my intake gaskets. Even into the thermostat port. So I guess now I'll be replacing those I had not used RTV except on the china wall. I supposed I should though now when replacing? Or is this something that could be expected if the engine is upside down?

 

The oil likely went past the rings and entered into the intake ports. Find the cylinder with the valves closed and check those ports. I bet they are dry.