Oil Pressure
 

We have a 2000 Checkmate 259 Convincor powered by a stock 454MAG. The boat has logged 189 hours. This year I have noticed the oil pressure gauge find itself in the L speckled paint side of the gauge at idle after a hard run. Is this something to be concerned about? When the engine is cold oil pressure is strong at idle. The only time the oil pressure drops is after running the boat for an extended period of time at or above 4000RPM and then idling. Could the oil in the boat be the wrong viscosity? Oil level is good and clean. Any thoughts would be appreciated.

Re: Oil Pressure
 

Several things are happening. Your oil is getting hot and thin, and possibly foaming. After a long run your oil will get a little air entrained and will show lower on the gauge. Probably why it hasn't appeared in past years is because your engine bearings have a little more clearance than before. As long as you have decent oil pressure while at speed, this shouldn't be a problem. Do you have an oil temp gauge too?

Re: Oil Pressure
 

what oil are you running ???????

Re: Oil Pressure
 

10psi for every 1000rpm is ok!(when warm)

Re: Oil Pressure
 

I am not sure. We have a marine mechanic winterize the boat once a year. I will ask him.

Re: Oil Pressure
 

Our oil pressure gauge has L to the left and H to the right with speckled paint close to the L. No numbers on the gauge at all. Maybe I should buy better gauges.

Re: Oil Pressure
 

No oil temp gauge. Thanks for the insight.

Re: Oil Pressure
 

also kind of sounds like someone may have installed a multi visc oil... if so .. change to a straight weight.

Don

Re: Oil Pressure
 

I have noticed the same on my boat, 454 running the merc multi viscosity mercruser oil. I don't think merc sells a straight weight, at least i haven't seen it.

Re: Oil Pressure
 

ALL of my boats have done this after a long, hard run. If it didn't do it before they may have used a lighter weight oil when they winterized.

Re: Oil Pressure
 

he speaks the truth, I have seen many mech ( notice I didnt say techs, yes there is a differance ) use 15-40 and it will do just what you are saying


use either 25 40 merc oil or SAE 30 OR 40 straight weight dont be alarmed if it says diesel oil

and check the filters if he used frams change them to merc or wix


oh and if he did put any thing in other then stated above find someone that knows what they are doing to work on your boat

Re: Oil Pressure
 

joe,
whats wrong with fram filters?

Re: Oil Pressure
 

mostly low flow rates which is everything along with the micron rating stucks ( they are ok for cars that run 1500 rpms all day but when was the last time your boat cruised at 1500 rpm) with the Wix filters they are about the best production filter ( merc filters are made by Wix ) they cost alittle more but you tell me .......

peace of mind..........priceless

Re: Oil Pressure
 

thanks