I have twins so here is my issue. Both motors when first started have 80 psi. When warmed up and running, both have same psi, around 60. When I run hard, come back to no wake speed, one motor drops to around 25 psi. The other motor sits at 50. After a few minutes the low one climbs back up to 50. I know 25 psi is more than enough at idle. Question is, they used to run identical pressures. Gauges and senders all check out fine. Oil cooler is clear of any water restrictions.No real way to check oil side of cooler. Multiple oil filters have been tried. What might be happening ?? What am I missing ??? These are Gen 5 motors with 125 hours. The problem started at 85 hours.

Smitty

Smitty, did you check with a mechanical gauge just to be sure? i had the exact same issue before, freaked me out a little. I put a mechanical gauge on it, and the one showing 25psi on the dash, was actually around 45psi at idle on the mechanical.

Bad cooler? It sounds like the cooler is in some way restricted.

could be several things.1 oil might be getting a little hotter on one engine.2 one engine might have a little larger clearance,s than the other.3 one may idle a little slower than the other,or like joe said,could be a sending unit issue.electric gauges are not as accurate as a mechanical gauge.imo,you have nothing to worry about.

get an infrared gun and shoot the oil filters, that will ley you know if you have comparable temps

I will try the temp gun and see if a mechanical gauge will show the same. Problem is I swapped senders and no difference. I am thinking cooler issue. Maybe remove it and have it boiled out ?? How do you get them clean other wise ? And no motor failures to plug it up with metal. Or maybe swap them from other motor ???

Want there a filter issue previously discussed that did this? fram?

Something to do with oil Tstats? or bypass valves?

Sounds like the one could be getting airiated?sp pressure returns when settles out, maybe try a half qt less then add a qt to see if there is any change. Easy test and only costs you a qt of oil.

At least the pressure comes back, lol, so many other boats not so lucky.

Is it the same condition even immediately after an oil change? Try to shoot the oil pan temps as well. Luckily it seems to be just an annoying anomaly.