Hey guys,

hoping someone has a stock oil pump laying around and can pull the pump spring out and give me a measurement. I believe I am running a HP spring and I want to reduce to a stock oil spring. I'd like to verify my spring is HP. My spring measures about 2.135" long. Let me know if you need anymore measurements.

thanks

Was pretty sure I saw the length listed in the FSM and found that it is. At the end of the oil pump section in the Engine Lubrication chapter. 52.5 mm free length, Page EL-4.

Are the HP springs longer or do they have a different wind or wire thickness?

Are the HP springs longer or do they have a different wind or wire thickness?

Good question?

I'll link this thread just for reference. I don't think it has spring lengths posted, but it's a nice comparison.

The spring still shows as available at Courtesy, if you just want to start over.

SPRING-VAL

15133-21000

Found 'em here (I love this site) - http://www.carpartsmanual.com/datsunS30/DatsunZIndex/Engine240Z260Z/OilPump/tabid/1572/Default.aspx

The 280Z pump parts appear to be out there also.

The 1972 FSM specs the free length at 57 mm (2.24 inch). Opening pressure is 54 to 60 PSI.

The 1973 free length is 52.5 mm (2.067 inch). Opening pressure is 52 to 61 PSI.

1975 is the same as length as 1973. The oil pressure is not specified however.

What is your oil pressure when the engine is cold? If it is close to 60 PSI you have a stock spring.

Leon, nice thread- thanks.

I have someone sending me a stock spring to compare. I believe my spring is thicker winds thus stiffer.

Oil pressure is 60 when warm- at idle!

I have been fighting a leaking rear main and want to look at oil pressures closer. I am going to run a mechanical gauge in parallel with the factory gauge to verify readings

Does the oil pressure ever go higher than 60 PSI? The pressure regulator determines the maximum pressure. If the pressure never goes past 60 you have the correct spring.

The FSM states the oil pressure should be 14 to 17 PSI at idle when the oil is 176 degrees. To have 60 PSI at idle with hot oil suggests a high volume pump, a faulty gauge, or restrictions in the oil passages.

Thanks for the info - I need to put a mechanical gauge on there. I noticed on the video I made that my pressure was at 60 at idle. I am on my second rear main seal and it is still leaking. I have searched and excessive pressure manifests itself sometimes with a leaking rear main. I DO have a high volume pump with HP spring, not sure about an obstruction.

Okay guys, revisiting an old but still lingering issue. I still have a rear main seal issue, but not as bad.

I will cut to the chase, I removed my oil pump to examine the passages and to check everything out. Am I missing something here, there was no ball under the spring. There was a piston type deal under the spring, but no ball anywhere. I have been trying to find a breakdown illustration, but everything I found shows a ball and spring. This is a high volume pump from MSA.

I'd appreciate some insight here.