High oil pressure

[Paul Bellefontaine]

Hi all. I have a QSB 5.9 in a 2006 Mainship 400 trawler with 2600 hours. Oil and filters are changed regularly. Pressure normally reads 52 to 54 psi at my normal cruising range but the some days for no apparent reason shows 74 to 78 psi.
Q1? What is the cause and repair?
Q2? Any harm risked by the high oil pressure? My owners manual says it should be regulated at 50 psi.

Thanks Paul

Topic

[Rob Schepis]

Filter is good. Did you set up the mechanical gauge?

[Paul Bellefontaine]

Filter correct? If not electrical?

Hi Rob.
1) Can I assume from your answer that the LF3894 is the correct filter??
2) I had the high oil pressure again and as an experiment I shut down the engine and restarted which lowerd the pressure to the usual mid 50,s. That would seem to rule out electrical. What would be the most common mechanical cause? Bad springs in the regulating mechanism? The filter bypass system?
Thanks for any help you can give. Paul

[Rob Schepis]

Gotcha. As said above time, for that mechanical gauge: https://www.sbmar.com/product/smx-mechanical-oil-pressure-gauge-kit/

[Paul Bellefontaine]

Thanks

Thanks Rob and fireisland. Yes it did it before last change. Filter is LF 3894. Engine is a 380. Your thoughts are appreciated. I have another issue that I am saving for a separate post. Paul

[Fireisland1]

I would put a mechanical gauge on the engine to verify readings. Mine is 49psi @2000 rpm hot.

[Rob Schepis]

Did this ever happen with the prior oil filter?
What exact filter are you using?

[Author]

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