I have an XH XR6 and I'm having problems with very high oil pressure. When I say high I mean high. It's almost off the gauge.

I was running GTX Gas which is 15W/40 which provided high pressure so today I changed to Penrite Gas which is 20W/60. That didn't do anything so I changed it AGAIN to Castrol 10W/30. This is a little better but not much.

As you have probably worked out my car is dual fuel and I mostly run on gas.

What could be casing this? What are the potential dangers? What damage will it do? How do I fix it?

Any advice would be good.

O.k.,: first you need to determine if your guage is giving you the correct info.
This can only be determined by fitting #1:an analogue gauge to the system and making a comparison, or #2: by checking the electrical output of your sensor, or #3: buy installing a new sensor and seeing if there is any change, or #4: by replacing the guage.

If your oil pressure is that massive, the only real damage that may be done is to the hydraulic valve lifters, as such an oil pressure may blow them apart.

As a comparison, I ran a Cleveland with 120 psi pressure at start-up, and consistent 100 psi running for years, with no problems whatso-ever. Whatever you do, do NOT fit a high volume oil pump, as damage can occur to the drive shaft for the pump.

As far as your problem is concerned, I would first check the guage.

you could try running a flush through the eng. they can bought from repcp, etc. this should loosen some crap stuck in the block

if after checking your gauge is giving the correct reading. there is only one thing that can cause high oil pressure. the pressure valve in the pump is stuck closed and can not bleed off.

what ever you do, do not under any cirumstance put engine flush in your engine. you'll do more harm then good

So if the pressure valve in the pump is stuck open, what do I do?

Stuck closed!!!!! If your pressure is high, and assuming the valve is the problem, then the valve is stuck closed.

It means new pump or recon the old one. This is a big job as it usually means dropping the sump which means dropping the K-frame, or lifting the motor!

I will almost guarantee that your problem is your oil pressure sender (on the passenger side, half way up the block about 1/3 of the way towards the back of the block. They are a cheap fix and 90% of the time this is what causes the high pressure reading!

I agree with philladdis, check the sender, guage and hope it's not the relief valve!!!

Given the position of the sender, which would be the best way to attack. From the top of from underheath?

Also how much is a new one, and can you get non-genuine?

the sender is a pain to get at, I would attack it from underneath I think. I also think you can buy a special socket for them too.

I think they are about $20 odd.

DO you mean the socket it about $20 or the sender is $20? Can you buy non genuine, or is this price non genuine?

Definately easier to get to from underneath than from the top...especially with the 6's.

You shouldn't need a special tool at all. I got mine out with an adjustable crescent.... and the replacement was not that much at all. About $80 sounds about right!! (that's original)