rmaynard 15,631 #1 Posted January 14, 2015 While hunting for the causes of oil leaks on the 416-H, I stumbled upon multiple references on other forums to the fact that the oil pressure switch can leak. Not at the threads, but from the body. Checking the price of a new Onan switch, I am now looking for alternate pressure switches. Does anyone have a suggestion for a cheaper switch? Mine is 2-pole with an internal ground and NC and NO spade terminals. The info on the switch is: Hobbs Corporation Springfield, Il. The numbers stamped on the case are: 80425 5 5 9611 I have tried crossing those numbers with no success. Hobbs was purchased by Honeywell, and when I search the Honeywell site I come up empty. Share this post Link to post Share on other sites
sorekiwi 761 #2 Posted January 14, 2015 On my 520 I just used a generic single terminal switch from the local autoparts store. Sorry, no part #. It cost about $6. I dont remember what I did with the wiring, it was pretty simple. My switch is NC until the engine has oil pressure, and switches to Open at about 8 psi Share this post Link to post Share on other sites
rmaynard 15,631 #3 Posted January 15, 2015 (edited) I have found a PS-122 switch that I think may work. It has 3 terminals. One terminal is common and would need to be connected to ground, One is normally closed which would be connected to the dash light. It opens at 2-7 psi, turning off the light, and the third is normally open. It connects to the hour meter and closes when 2.5-12 psi is reached. That keeps the hour meter from running unless the engine is running. It's only about $5.00. I will only used it if I determine that my original pressure switch is leaking. By the way, Honeywell did get back to me. They have a replacement for the Hobbs switch. The part number is 76582-00700070-01. "NC" opens at 7 psi, and "NO" closes at 7 psi. Trouble is, the price is more than a new Onan switch. Go figure. Edited January 15, 2015 by rmaynard Share this post Link to post Share on other sites
boomers_influence 106 #4 Posted January 15, 2015 bob the problem with the PS-122 switch, in my opinion is TOO MUCH variation as to when it opens and or closes, on each end of the spec. BUT, in the long run it most likely better than NO switch at all. thank you. boomer Share this post Link to post Share on other sites
6bg6ga 272 #5 Posted April 12, 2017 Maybe there is another way to skin a cat. Plumb in a oil pressure gauge along with the pressure switch. You could operate your idiot light as well as a low pressure buzzer and your hour meter or simply have the hour meter run in conjunction with the run position on the ignition switch. 1 Share this post Link to post Share on other sites
