Engine/Transmission (1998.5 - 2002) Why oil pressure change?

[PBayer]

I sold my 2001 auto and got a 02 w/6 speed. No love for the auto even w/DTT or any other trans company up grade. JMO. Upon stripping my 01, when I removed the amsoil remote by-pass filter setup and put on a napa gold filter. Same oil in engine. With the amsoil filters the oil pressure crusing was 40 psi and with the napa gold 55ish psi. Noticable difference on the dash gauge. Any logical reason why?

THX Paul

 

[Car_nut57]

Sounds like you were not getting full flow through the Amsoil filter.

 

[Whitmore]

Greg

Maybe the NAPA filter has a bigger micron allowing for less DP across the filter, I would try a Fleetgaurd on your next change and see what it does... ... ... Kevin

 

[illflem]

Originally posted by Dave - Diesel Power Products

Sounds like you were not getting full flow through the Amsoil filter.

Seems to me it would be the opposite. The bypass was "robbing" the oil system of pressure by dumping down the sump rather than adding to system pressure. A bypass system could almost be considered a controlled leak.

 

[McDowra]

illflem you have a interesting point. If your correct then a bypass system causes the motor to see less oil pressure and volume. Can that be right?



Tim

 

[illflem]

Tim, lower oil pressure can be the outcome if the bypass flow isn't somehow limited. That's why most bypass systems have restrictors to keep the flow down.

 

[PBayer]

I just disassembled the bypass unit. It contained a spring and a plunger. The plunger isnt solid. It his a 1/4 hole in it. I would think it should be solid so not to let the oil bypass unless the primary filter is at max operating capacity.

 

[BarryG]

If I remember correctly that is a common outcome of the dual bypass system. Don't know about the single bypass types out there. Don't know why it does it either. I can say that I don't like it but do put up with it. The Amsoil dual bypass only allows like 5 or 10 % of the oil flow into the bypass filter at any given time. I do not know if it has some type of safety mechanism or not regarding the capacity of the full flow. You have added 3 or 4 feet of hose, an additional filter, and I think a larger full flow filter. Could it be that the oil pump just can't create that type of pressure with that extra amount of space and volume at the rpms it is running. Just thinking out loud there.

 

[Ron Bissett]

PSI ?

Napa more restriction =higher PSI , reason Pumps make flow restriction makes Pressure . as to by pass Cummins has a spec on that orifice and max amount of oil per hour . Hope this helps , Ron Bissett in LOUISVILLE KY