I was thinking the same thing but ran the boat all last year and the presure was pretty steady at 60. That engine was rebuilt and had 20 hours on it when I bought the boat (so I was told anyway)

What was the oil temp? both engines running the same oil temp?? if one is running much higher then other you have something to look into...

A BBC will eat bearings if you cant keep the pressure up at idle 15-30 is normal, I personally would not accept less then 55-65 under way hot or cold...

I run HV pumps with shims I get 80 cold running and idle, once I am warmed up, it has 60-70 running and 35-40 at idle, I learned the hard way you need a good oil pressure on BBC ... I went through hell a few years ago and it was all because I didn't have the right pressures/pumps

I am having the same issues in my 454. Pressure is up around 60 when cold after it warms up it's around 40 when cruising, after coming off a hard run it drops low like down to 10 at idle speeds, goes up to 15-20 in neutral but under a load back to 10 until I give it some rpms then back up. Thought the oil was getting hot so I checked my cooler and it's all good. Does anyone know if these motors have a thermostat for the oil?

Gonna change my oil tonight. I use merc 25w-40 or is it 15w-40. Either way I'm switching and gonna try valvoline racing I think its 20w-50. I was told straight 50 is way to heavy I'll post any changes tomorrow since I'll have the boat out.

Good luck with yours.

minimal 10psi per 1000 rpm.... I woukda not accept less... now also make sure senders and gauges are accurate... put on a mechanical gauge to be sure... you could have senders off too...they are electric...

change the oil and go from there . could simply be oil dilution . did you have a hard time starting engine ect . does the oil smell like fuel ?? alot can happen to oil . if you suspect clearence issues open up youre filter . proof is in the pudding

I had trouble in the spring starting it for the first time but that was I believe a battery issue. It starts fine everytime now.

I'm hoping it's something with the oil. Oh and I do have a mechanical gauge in to verify.

the reason i asked about prob starting , if you have access fuel in the oil it will show low oil pressure. flooding of the engine ect . you need to change the oil and see what happens

Oil was black and not much viscosity to it. Wierd for only being out a half a dozen times. No shavings in the filter either. I'm running it on the third so we'll see how it does when hot.

I spun a main bearing last year, But it only rotated about 3/4 inch on number 2 main. When the motor got hot the pressure would drop sometimes to around ten and my alarm would just beep a couple times, But as soon as you gave it just a little throttle it would jump up to 40 lbs. No metal in filter(cut it apart) changed oil, a little better until it warmed up. This was a stock 330 with around 300 hours on it (stock).

Oil stayed up around 20 after a descent run, and I figure thats pretty good with mid 90 temps all week long. I'm thinking oil is getting in the crankcase some how so its either from the carb or fuel pump.