Duramax7man7 505 #1 Posted June 27, 2017 So through my endeavors, I'm considering replacing the least useful gauge on one of my 520h tractors with an oil pressure gauge. What would you consider the least useful gauge? The Vacuum gauge or should I keep them all and add the oil pressure gauge somewhere else? Thanks. 2 Share this post Link to post Share on other sites
Achto 26,545 #2 Posted June 27, 2017 If I was going to ditch one gauge, it would be the vacuum gauge. 2 Share this post Link to post Share on other sites
cleat 4,947 #3 Posted June 27, 2017 I will second that one. Vacuum gauge serves me no real purpose and just vibrates around at idle. I was also thinking about an oil pressure gauge. Any idea what the Onan's run at ? 1 Share this post Link to post Share on other sites
Duramax7man7 505 #4 Posted June 28, 2017 If memory serves me correctly, my 1970 P2215 Onan is rated for 35psi warm @ 1800rpms. But it has rod bearings and an adjustable OP screw and nut that holds the bypass valve and spring in. So not sure if those factors would change the situation. Share this post Link to post Share on other sites