oil pump turning torque?

tortuga · #1 (**permalink**) 07-30-2020, 07:41 AM

after getting my new heads on and valve train all setup, i thought it would be a good idea to run some (new changed fresh) oil through the valve train...I couldn't get an SAE deep socket (didn't have the right one) to fit the oil pump drive, so i found a metric one that fit close, not wanting to screw up the dive i just put a speed wrench on it and turned by hand.

VERY surprised how hard it was to spin the oil pump? I did get oil up through the lifters and through the rockers, but man lots of torque required?

Is this normal?

bobcowan · #2 (**permalink**) 07-30-2020, 08:28 AM

Yes, that is pretty normal. If you use a drill motor, you have to use a 1/2. It's worse if you're using a really thick oil, like 15W-50.

tortuga · #3 (**permalink**) 07-30-2020, 09:12 AM

Thanks Bob!

cycleguy55 · #4 (**permalink**) 07-30-2020, 11:26 AM

Quote:

Originally Posted by tortuga

after getting my new heads on and valve train all setup, i thought it would be a good idea to run some (new changed fresh) oil through the valve train...I couldn't get an SAE deep socket (didn't have the right one) to fit the oil pump drive, so i found a metric one that fit close, not wanting to screw up the dive i just put a speed wrench on it and turned by hand.

VERY surprised how hard it was to spin the oil pump? I did get oil up through the lifters and through the rockers, but man lots of torque required?

Is this normal?

Like Bob said, it's normal calls for a 1/2" drive drill. The first time I did it the drill and pump ran for a while before building pressure, then WHAM, hold on tight to the drill. That was a Melling high volume pump on a 460, with 5W30 oil. It typically runs 80 PSI on a cold start fast idle and around 25-30 PSI on a hot idle, so bearing clearances are moderately tight.

olddog · #5 (**permalink**) 07-30-2020, 09:42 PM

.... and now you know why the manufacturers are going to lighter oil. Less power used to turn the oil pump means better fuel mileage. Other reasons too, but this is one of them.

Michael C Henry · #6 (**permalink**) 07-31-2020, 05:19 PM

When I bought my car one direction from previous owner to not get carried away with rpms until oil temp shows a minimum of 140°. I sheared the distributer drive gear pin once.