12HT Oil Pressure Problem? (1 Viewer)

[KeepCruzin]

Hey guys. So iv had my 12HT in my FJ60 for about 5k miles now.
My oil level is good (right on the F line)
I fill with Rotella 15-40 every 3k miles.

I recently replaced my oil pressure gauge (not the sending unit, the gauge in the dash)

The gauge is from an FJ60 dash.

The oil pressure seems very low. At idle, it's in the middle of the bottom white bar, and at 2,500 rpm it is only between the first and second white bar.
Thoughts?

Oil pressure at 2,500rpm

Note- there is a very small oil leak from the bell housing (I suspect rear main seal) it's about 2 drops per hour by my estimate

 

[Tapage]

never trust on those factory indicators .. get a good aftermarket oil pressure gauge and you will know for sure your oil pressure ..

 

[traveldud]

I'll be curious what you discover as I have a similar arrangement and similar observation. Fingers crossed no problems.

 

[roma042987]

That's where mine was at when when it started knocking. Had a new sender in mine. I've had about 10 cruisers now and with a new sender I trust the factory gauge. In my experience they aren't as inaccurate as everyone states.

 

[roma042987]

Just reread your post does picture show it at 2500 or at idle?

 

[KeepCruzin]

Just reread your post does picture show it at 2500 or at idle?

2,500 rpm

 

[dousty]

Assuming your sender and gauge are working fine, it's too low. Pull the sender out and hook up a hand held gauge to confirm.


Side note: Are the FJ and HJ dash units the same?

 

[watrob]

ok, your first problem is if it's the synthetic version, get rid of it out of a 30 year old engine? drrrr my rear seal is leaking??????
2h & 12ht engines need a heavy oil, your are running the oil thru a turbo, synth as it gets hot it gets thin?

Rotella is a good oil, but ask the question why do truckers add Lucas, Rotella lacks Zinc dithiophosphate, since it was reformulated, your need high Zinc, you have added a high detergent oil??

Bet my left nut, do an oil change, fill it with mineral 15w40 and the gauge will double? 2H & 12HT need a heavy oil.

How do I know, been running 2H & 12Ht engines for years.

There are numerous threads on here with OP's going to mineral which fixes the problem.

 

[roma042987]

put a new sender in it and recheck. was your engine out of an auto or manual truck?

 

[KeepCruzin]

ok, your first problem is if it's the synthetic version, get rid of it out of a 30 year old engine? drrrr my rear seal is leaking??????
2h & 12ht engines need a heavy oil, your are running the oil thru a turbo, synth as it gets hot it gets thin?

Rotella is a good oil, but ask the question why do truckers add Lucas, Rotella lacks Zinc dithiophosphate, since it was reformulated, your need high Zinc, you have added a high detergent oil??

Bet my left nut, do an oil change, fill it with mineral 15w40 and the gauge will double? 2H & 12HT need a heavy oil.

How do I know, been running 2H & 12Ht engines for years.

There are numerous threads on here with OP's going to mineral which fixes the problem.

Its non synthetic. Iv never run synthetic through my 12HT.
Iv been running either Dello 15-40, or Rotella 15-40. Now that you mention it, my oil pressure was always higher with the rotella, and now with Dello in it that may explain the drop. The pressure is always higher when i leave early in the morning when the oil is more viscus.

I will look into this for sure.

 

[KeepCruzin]

put a new sender in it and recheck. was your engine out of an auto or manual truck?

It came out of a automatic. Its manual now.

 

[roma042987]

It came out of a automatic. Its manual now.

had any problems with the drive belts?

 

[roma042987]

It came out of a automatic. Its manual now.

had any problems with the drive belts?

 

[Oldtoy74]

Factory gauges and the senders tend to some what unreliable with oil pressure, best to get a mechanical gauge and test, my pressure always look to low from a gauge perspective, but check warm idle test and then 2000-2500rpms test, pressure on warm idle in FSM is generally low anyway,

 

[KeepCruzin]

Ok so after a 45 minute drive, the oil pressure gauge is at the 1/3 area of the LOWEST third (if that makes sense it's about 1/9 of the full gauge at 500rpm idle)

 

[KeepCruzin]

Ok so after a 45 minute drive, the oil pressure gauge is at the 1/3 area of the LOWEST third (if that makes sense it's about 1/9 of the full gauge at 500rpm idle)

 

[Oldtoy74]

650rpms standing idle for manual, 750rpms auto just for your ref

 

[KeepCruzin]

That's after an hour of driving at standing idle

 

[dousty]

and the actual pressure reading?

 

[Oldtoy74]

From a guage perspective it's looks normal where the needle sits on idle, get a mechanical guage put your mind to rest