Re: Yanmar Oil Pressure Pegged
What weight oil? If it is too heavy (viscous) the pressure will build up in the manner you are seeing until the oil heats up.
If the weight is right I think it's more likely your pressure sender is "off" than the relief valve is at fault.
"It's not what you know that's important...it's what you do with what you know." -H.G. Rickover