# Generac 4000EXL



## Curious_George (Nov 2, 2012)

Hi All,
Just wanted to stop by and give some cross reference information. I know the Generac 70185 oil filter has been crossed to various automotive filters... I used an STP S4967 which is a very common filter and worked perfect. Same threads and gasket mating surface. It is slightly longer (10mm maybe), but on the 4000EXL this is not a problem. I suspect on most generators that use this filter, the extra 10mm will not be a problem.

My low oil pressure switch was also not working and leaking. When I attempted to start the engine, it would run for about 10 seconds then stop. Disconnecting the 2 yellow wires bypassed the switch and the engine remained running. This seems to be a common problem with these switches. 

Not wanting to order a switch and have to wait, I noticed how similar the Generac OP switch looked to the OP switch in my 1987 Suzuki Samurai. Both switches are grounded with no pressure. With 4~9PSI both switches open and break ground. The 1/8" threads are the same too. I used some pipe tape (PTFE tape) on the threads before threading the new OP switch into the oil adapter / appliance. Autozone has part number PS123 for $8.99. 

The only small difference is the Generac OP switch has a screw stud for the wire connection, the PS123 has a flat male spade. This was not an issue for me as I have a crimper and an assortment of crimp-on connectors. In this case, a blue female insulated spade was put on the yellow wires and connected to the new OP switch (PS123). 

There you have it, common parts to fix your generator and it won't cost you 10 times what it should. 

Nick


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## Apple211 (Jan 29, 2015)

thank you for the info.


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## Desy 20 (Oct 12, 2017)

Useful information! Thanks you!


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