MEP-831A High oil pressure

[Scott12254]

Hello everyone just picked up a MEP-831A generator and through some checks found the oil pressure to high. I have replaced the filter and drained and filled with fresh 15-40 oil. I hooked a mechanical pressure gauge to the oil pressure port and it was 160 psi. Do these engines have a pressure relief valve? Aside from tearing the engine down any other suggestions? Thanks

 

[kloppk]

The 831's do run at a high oil pressure.
Mine with the factory break in oil runs at about 130 PSI at startup.

 

[Scott12254]

So nothing to worry about then? I was concerned that it might have a blocked passage so I have not run it for more than a minute. I have found it difficult to find engine specs for the YanmarL70AE engine through Google searches. Does anyone know a place to get those? Thanks to this site I was able to track down the illusive Nason oil pressure switch for the unit

 

[Demoh]

These generators dont have any form of oil pressure relief. The relief is only an orifice. They are known to be almost 200psi on cold startup.

Red arrow is this orifice. Other picture gives you an idea of the size compared to the engine. I think this was an L48, not an L70, but lots of same parts. I took these pictures while visiting my local yanmar expert/dealer picking up parts.