Here's a little history. I blew a motor last year. I rebuilt both motors. They are Gen V 502's. Put them back in went out for a run and blew the port motor. Spun two rod bearings and heated all the mains. I did not have an oil temp gauge at the time but I figured the problems was caused for extrem oil temp. As the oil and allt the bearings were very burnt.
Here's what I did to try and resolve it. 1 rebuilt motor new crank and rods from GM. rods and main clearances are at .0025 to .0030. I installed 30lb bypasses in both motors. Installed Oil temp gauges. Sender in pan and one at remote filter.
I first ran the motor on a stand out of the boat with a regular filter on it. Oil pressure was 75lbs and would climb to 80 on a good rev. Oil temp was around 180. Once the motor was broke in, I put on the remote cooler and filter assembly. Pressure dropped to 60 and oil temps to 170 at both the pan and remote filter. I was not running water throught the cooler.
Now here's the crazy part. I put the motor in the boat changed oil to 40wt break in oil was 30wt. The remote oil and filter assembly was not removed since the break in run. I started the motor and I only had 40lbs oil pressure. I switched the filter thinking maybe I had a bad filter. Same thing 40lbs oil. After running the motor for a short bit to get the oil temps up the oil in the remote cooler was cold while I had 180 temp at the pan. the oil in the filter was cold also I mean cold like the motor was not running. Seems all of the sudded no oil was going through the cooler or filter.
The other motor had 180 at both filter and pan. Both motors have the same cooler setup and the lines are all ran the same. I checked the path of water and oil and its all fine. There are no kinked hoses. I ran mineral spirits and blew air through all oil lines and and coolers before I put them on and everything flowed fine.
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