I have an AEIO-360A1E. TTAE is 680 since new. It has a hartzell constant speed prop and govenor. The prop and govenor were overhauled about 5 years ago. It has a US Gauge 3 1/8" mechanical oil pressure/oil temperature gauge (the kind that are no longer available, but commonly found in Super Cubs.)
During cruise at various power settings, the oil pressure needle fluxuates rapidly between about 75 and 85psi - almost (but not quite) so fast that I can barely see the needle. Then, periodically (but continuously) it will also drop momentarily down to the bottom of the green arc, and then bounce right back up, resuming the 75-85 psi fluxuation. It does not do this at idle. Oil is continuously run at 6 quarts, and it has not even used a quart in the last 8-10 hours. If I run at higher or lower power settings, it does the same thing- just at a slightly higher oil pressure. Same thing for lower power settings.
It has a Christen inverted oil system that is standard on the AEIO engines. There are no oil leaks - engine is dry.
Some have told me it is instrumentation, and that I should replace the gauge.
Thoughts or recommendations before I start tearing into it?
During cruise at various power settings, the oil pressure needle fluxuates rapidly between about 75 and 85psi - almost (but not quite) so fast that I can barely see the needle. Then, periodically (but continuously) it will also drop momentarily down to the bottom of the green arc, and then bounce right back up, resuming the 75-85 psi fluxuation. It does not do this at idle. Oil is continuously run at 6 quarts, and it has not even used a quart in the last 8-10 hours. If I run at higher or lower power settings, it does the same thing- just at a slightly higher oil pressure. Same thing for lower power settings.
It has a Christen inverted oil system that is standard on the AEIO engines. There are no oil leaks - engine is dry.
Some have told me it is instrumentation, and that I should replace the gauge.
Thoughts or recommendations before I start tearing into it?