Horse Newbie 7,302 #1 Posted May 6, 2023 Ut-oh !… trouble maybe ? Hey guys I washed my 520H and now the oil light on the dash is flashing.😡 Do you think it could be from water getting around/ on the oil pressure switch ? IMG_2317.MOV 1 Share this post Link to post Share on other sites
Horse Newbie 7,302 #2 Posted May 6, 2023 Went back to the 520H, turned on the key… oil light blinking. Cranked it, oil light went out… Guess it’s okay… no strange or different noise heard. 2 Share this post Link to post Share on other sites
kpinnc 14,206 #3 Posted May 6, 2023 (edited) I've seen a couple 520s do that, even when full of oil and obviously making good pressure. Glad yours stopped when it dried out. I'm sure if you had an oil pressure problem, you'd know by now for sure. I'm not 100% sure for the 520, but most pressure senders just open when pressure gets above a certain point. The rest of the time they ground the circuit. On Vanguards, they go to the magneto so they kill the engine if the pressure drops. Edited May 6, 2023 by kpinnc 1 1 Share this post Link to post Share on other sites
Horse Newbie 7,302 #4 Posted May 6, 2023 Can’t remember too well, but I couldn’t find a OEM pressure switch when I first got the 520H… So I had to get (I think) a switch with 3 or 4 terminal posts, one went to ground even though the switch grounded through its body, one went to the dash light /warning light panel, and the other went to the hour meter. I think the hour meter only runs when there is oil pressure/ engine running. That way if you leave the key on it doesn’t run up your hour meter. Sound right ? 2 Share this post Link to post Share on other sites
kpinnc 14,206 #5 Posted May 6, 2023 1 hour ago, Horse Newbie said: Sound right ? Uh, probably. And for sure if you say so! My 520 has been butchered electrically. All the guages work, but I have no idea how. 2 Share this post Link to post Share on other sites
Bill D 2,200 #6 Posted May 6, 2023 3 hours ago, Horse Newbie said: Can’t remember too well, but I couldn’t find a OEM pressure switch when I first got the 520H… So I had to get (I think) a switch with 3 or 4 terminal posts, one went to ground even though the switch grounded through its body, one went to the dash light /warning light panel, and the other went to the hour meter. I think the hour meter only runs when there is oil pressure/ engine running. That way if you leave the key on it doesn’t run up your hour meter. Sound right ? Sounds right. Pressure switch body is ground. When the engine is off or there is no oil pressure the ground circuit is completed making the light blink. When the engine is running and there is oil pressure the ground circuit is completed making the hour meter run. Water probably shorted out the pressure switch making the light blink. 1 Share this post Link to post Share on other sites
Horse Newbie 7,302 #7 Posted May 6, 2023 7 hours ago, Bill D said: Sounds right. Pressure switch body is ground. When the engine is off or there is no oil pressure the ground circuit is completed making the light blink. When the engine is running and there is oil pressure the ground circuit is completed making the hour meter run. Water probably shorted out the pressure switch making the light blink. @Bill D, So if all is running well and the oil pressure drops while operating, then the light would also blink to alert operator to shut it down, correct ? 1 Share this post Link to post Share on other sites
Bill D 2,200 #8 Posted May 6, 2023 2 hours ago, Horse Newbie said: @Bill D, So if all is running well and the oil pressure drops while operating, then the light would also blink to alert operator to shut it down, correct ? Correct 1 Share this post Link to post Share on other sites
