Outer Limits 4x4 Board

Hey,

My 2001 Mk Triton 2.8 N/A Diesel has just eaten another oil pressure switch. This is the 3rd one since I bought it in late 2003. Any ideas on why this keeps happeneing?. Its not a big job nor expense to put a new one in, but when the switch lets go, oil goes everywhere through the engine bay so a detail of the engine bay is required which takes longer than replacing the switch.

So just wondering if others have this issue, and what goes into making the pressure switches fail. And is there anything that I need to do or check to stop this happeneing again in the future.

Thanks

Adding to all this.

I went to an aftermarket supplier like auto one, and got a new switch from them. Saved $50 from genuine mitsubishi part, as if I remember correctly the last one I bought from Mitsu was $60.

20mins later, wallet $50 heaver, and all is good again. Would still be interested if anyone has ideas on why they keep going though.

Thanks

At a guess:

The Mitsubishi oil pumps I've seen (all two of them) have an over-pressure bypass - once pressure reaches a certain pressure, a spring-loaded plunger opens and allows oil to bypass the oil filter, keeping the pressure down. On my Galant, this plunger would stick while the engine was cold, and oil pressure would hit 90psi or more. Once it opened, pressure never got above 60psi.

If the 2.8 has a similar mechanism, and yours is jammed, your switches may be failing due to excess pressure.

Can you (temporarily or otherwise) install an oil pressure gauge?

Good luck,

Scott

I guess I could, although apart from the current hassle every 12-18 months, will it be of any benifit.

Am I doing damage at while the engine is cold if the switch is jammed open. Or is it just losing a tiny bit of oil? (seems alot of oil, but I guess as it would be coming out at pressure it is probably not much at all)

Too much oil pressure could be bad. We had a falcon with a jammed relief valve and it kept blowing the oil filter apart. This was very messy. I would remove the sender and pop an oil pressure guage in there to see what pressure it runs.

Just thought I'd mention that i've done an oil pressure switch in mine, after a day in the dunes. Yes, very messy.
Maybe I should start counting....

Just digging this topic up again as I have blown another oil pressure switch. Has anyone found out anything further on this problem?