I noticed on my last trip in the Gen I Montero, my oil pressure guage stayed at the first line I believe it just says "2" at the first line then "4" then "6" as the oil pressure goes up.

Is that normal? I would have thought on a long trip or higher RPM's that it would change or at least come up to about the middle of the guage, does this mean I have low oil pressure? I have new valve guide seals and not burning a drop of oil.

another thought, I'm running 31 Mud tires. I was able to easily maintain 75-80 MPH but RPM's were pushing 4000. Maybe these Montero's are geared lower than I thought, what is the gear ratio on the Gen I's?

Just curious, thanks dudes.

Stock oil gauge are very inaccurate and very slow responding.
After years of disatifaction and worry I undertook a very overengineered and heavy duty aftermarket( Autometer)mechanical oil gauge installation. With suggestions from folks on here to improve responce and accuracy , I now have no doubt were the pressure is at all times on my 3.0 SOHC.
20/50w castrol
ice cold idle: 80 - 100 psi.
hot idle : 15 to 20 psi.
under load on flat highway at 3000 rph in 5th: 50-60 psi.

Mine runs at near 6 at 50 mph. Best indicator is the dip stick.

Original pump on my 3.0 Raider 175k

80PSI Cold Idle
30PSI Hot Idle


Brand new Melling oil pump on my rebuilt 3.0 Montero

90PSI Cold idle
35-40PSI hot idle

I have the 2.6 with factory gauge. hot idle is around 3 and hwy speed is 4-6. For gears, stock is 4.62:1 for the gen1's.

The 2.6 engines typicly have very high oil pressure compared to the V6. The 2.6 pump runs at twice engine speed and in a high capacity pump. 110+ PSI cold and 80 PSI hot at highway speeds is normal on the 2.6.

The V6 does not need as high a pressure to live.

Kevin

Yes the 3.0 does run low, appearantly by design. Specs on All Data, FSM , etc. allow normals like around 15psi. Seemed too low to me but that's what's written.
My pump is a Melling , too,,,at least the gears are. The gears have around 45k on them , the body must be at 75k.

warm engine Idling oil pressure isn't too critical, as long as there is some pressure there you should be okay. my old 2.6 would hit 150psi on a cold start and when warm would idle around 50psi. Originally I only had a 0-100psi Automeater gauge and as soon as I installed it I wrapped it and wrecked it haha

If you get 150 psi on a 2.6 most likely your pressure relief valve is bad or someone shimmed it. It's designed to open at 110-120 PSI.

Kevin

Im curious if some people that are having the reading at 2 to 3 are reading the top numbers that are in orange? That is kg/cm, not the lbs/in which is the bottom numbers? I cant remember cold start lbs but my engine has alot of miles on it and I get 27lbs at hot idle and 45lbs at 55mph. And I need to change the oil... <img src="/forums/images/graemlins/rolleyes.gif" alt="" />