Oil Pump Replacement 67 3000

[R&M]

I would like to replace the stock pump with a new high output pump while the engine is still in the car. Is there anything I should be careful of when doing this? Any input would be helpful.

Thanks

R&M

 

[Dave Russell]

I think that a stock pump in good condition has more than enough flow capacity for a stock engine which is in good condition, Unless you have a race engine with purposely increased bearing clearances & the need for more bearing flow for bearing cooling, nothing will be gained.A high output pump is just a band aid for more serious internal engine clearance problems.

The only advantage of a high flow pump in a stock engine is to compensate for increased bearing leakages caused by excessive bearing clearances.

The down side is that much more oil ir run through the pressure relief bypass valve which just causes more heating & areation of the oil. It also puts more strain on the pump drive mechanicals, & comsumes more horsepower. If you increase the bypass setting to increase oil pressure it increases internal oil control problems with increased leakage & possible oil ring flooding.

If this band aid seems like the way to go, "do it"
D

 

[ThomP]

Somewhere out there on the web is an article on this subject. I was surprised by the results of the tests between the two Big Healey oil pumps and the high volume unit. The old style Healey pump and the high volume unit require 10 to 12 HP to operate at over 4000 RPMs while the later Healey pump only consumed 6-7 HP. The pressure differences were minimal (I think about 8 PSI) and the volume difference was most interesting with the old Healey unit moving 1/3 less oil than the later Healey unit. The high volume unit moved another 10% to the later Healey unit.

The conclusion was that a fresh, late model pump was the best bang for the buck.

 

[R&M]

Gentelmen

Thanks for your input on the high output oil pumps. Reason for my question was I had the engine rebuilt but oil pressure hot at idle is still only 10 pounds. I am looking at the loss in pressure possibly due to worn rocker arm assembly and will have that rebuilt. If that still does not solve the problem I will pull the oil pan to check bearing clearance with plastigauge and oil pump for wear. Just need to know if I should look out for anything if I change the oil pump with the engine still in the car.