This behavior appears to be normal. My '86 did this with a C223-T. I was running Amsoil Marine Diesel 15x40 in it.

I had the stock electric oil pressure guage in it, and replaced the sender. The guage read a little higher, but the behavior was about the same. According to Jerry Lemond, who has forgotten more about Troopers than I will ever know, this kind of behavior says it is normal behavior.

I don't like it either, but since these engines are known for being very long lived it must not be too much of a problem.


AP