Oil pressure

[Upper Mike]

Hi all, I have a 1999 Maxum 2800 with twin 4.3 mercs. Recently my oil pressure gauge has been reading high (just under 80) when running at higher rpms. No issue when running at lower rpms. Now the alarm has started to go off as well. Has anyone had a similar issue that can share how to troubleshoot? Thanks

[mmwjr]

In the Mercruiser manual for your engine there is a chart that tells you what the resistance should be for the oil pressure sender at several rpm. The manual can be found under Documents of this site.

Next you can use a manual oil pressure gauge to verify the pressure. Worst case is the pressure relief valve is sticking on the oil pump.

[Upper Mike]

Thanks appreciate the advice.