Oil Pressure Varience

[Thomv]

Should I be concerned that both of my motors are running different oil pressures while underway? My port motor is running 50 PSI while my starboard motor is running 42 PSI at 3,000 RPM. At idle both are about 38 PSI.

 

[achris]

Re: Oil Pressure Varience

Variations in the gauges and the senders could account for that... They are an indicator, not an absolute. If you need to know the EXACT pressure, you need to fit a calibrated mechanical instrument. At the appropriate price ....

Chris.......

Something like this -> http://www.alliedelec.com/search/productdetail.aspx?SKU=70238862

 

[Alumarine]

Re: Oil Pressure Varience

You could also swap the sender leads to the gauges to see if the readings are now reversed or not.
That would tell you if it's a gauge/sender isssue.

 

[Thomv]

Re: Oil Pressure Varience

You could also swap the sender leads to the gauges to see if the readings are now reversed or not.
That would tell you if it's a gauge/sender isssue.

Will give that a shot.
Thanks

 

[Levithan]

Re: Oil Pressure Varience

10psi per 1000rpm minimum is the general rule.
It could be senders or, one engine is a little looser than the other.
Those numbers sound fine though.

 

[Robert D]

Re: Oil Pressure Varience

10psi per 1000rpm minimum is the general rule.
It could be senders or, one engine is a little looser than the other.
Those numbers sound fine though.

Couldn't agree more. Even if the numbers are accurate, they are fine. A cheap way to check, get a mechanical oil pressure gauge and whatever adapter you need, to screw it in and verify the real pressure. Do it on both engines to double check, if the issue bothers you. I bought a glycerin filled pressure gauge, and have it mounted on my remote oil filter mount....just so I have 'real' oil pressure data. Something like this: New 3 1 2" Pressure Gauge 0 200 PSI 1 4" NPT Liquid Glycerin Filled | eBay or like this one that goes to 60 psi, which is what I have: Ashcroft 8923 Glycerine Filled Pressure Gauge 0 to 60PSI 1 4" NPT | eBay

 

[Thomv]

Re: Oil Pressure Varience

Last night I did have time to reverse both gauges. Over the weekend I will start both engines and see if the variance transfers into the opposite gauge.

 

[gm280]

Re: Oil Pressure Varience

With everyting stated above you could also have varients in the oil in each engine, even from the same manufacturer. Viscosity will change the older the oil is as well. But like also stated before the general rule of thumb is 10PSI per 1000RPMs is fine... Also check to see if one engine is running just a little cooler then the other. But I wouldn't worry the least bit if it were mine...