Why I'm I losing oil pressure? 502 new engine
 

Heres the deal.

Block, Crank and Rods 80hrs since new. and oil pump.

Just installed complete new bearings top to bottom.

New srp pistons and rings.

3" x 18" oil. Cooler and -12 oil fittings and lines.

Ran the engine 1.5hrs total time. 45 mins idle and 45 running no more than 4000k max. Most at 3500.

Ran 15 mins 3800 rpms. Backed off throttle and pressure went to 0

Idle. Cold 45
Idle warm 40

Cruise. 25-35
3800 had 40.

Running wix racing filter. Royal Purple 20-50 syn.

Engine temp 150-160
Oil temp never went over 195

Cut open the filter. Light silver dust. Seems light standard break in.

It does/ did have 11psi relief valve. Ordered 30 psi today.

Thanks OSO

fixx
 

just for ****s try another brand's filter..had a issue on a dirt track engine last weekend and we went from wix to a fram and picked up 30 psi of pressure..

is it HV pump? if not it's not going to have much more then 45-50 and that is scary to me, but a lot of them run ok with that if the clearances are ok, but oil temps tell you everything..... so keep an eye on em..

are you able to change that relief valve in the boat ?? i thought you had to thread a bolt and slap hammer them out, then press back in to install ??

Hiperf2000
Yes I changed it in the boat. Didn't improve the pressure.

Turns out the sender was getting oil behind the diaphragm and maxed the pressure at 40 psi. after a 20 min 3800 run. The sender was full behind the diaphragm. Then at idle, it's showed 0.

New sending unit 60 at idle cold. 55 warm.
2500rpms over 70psi.

Yea for me