still having oil pressure issues with 85 toyota truck 22r. have no oil pressure at start up and idle, you can increase rpm to appx 1500 and oil pressure will come up and maintain. had a cracked front cover so i replaced it and installed new oil pump for issue. also replaced rod and main bearings due to minor wear. checking oil pressure at engine oil port where sender screws in with a manual guage. changed engine oil to 20-50 castrol. Nothing i have done has made any difference to engine, desperate for any ideas.
1985 oil pressure problem
- Thread starter kr1969
- Start date
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Well it sounds like every part in the system has been either replaced or checked...so how confident are you in your guage giving you an accurate reading.
The only other thing I can think of is cloged oil passages, but I doubt that since you took the bottom end apart. You sure your pump is ok...?
The only other thing I can think of is cloged oil passages, but I doubt that since you took the bottom end apart. You sure your pump is ok...?
- Thread starter
- #7
confident because the idiot light also stayus on when i have it installed and have tryed three different oil pumps, two being melling pumps and one being asian. oh yeh also tryed another oil pressure tester. please come up with something i havent tryed
Did you install the bearings yourself?
does the truck have the dummy oil light, or the sr5 gauge?
if i read correctly, you mentioned that a light stays on continuously when you have your mechanical gauge connected right? so i assume you have the light only. not the sr5 gauge.
so it cant be a bad dash gauge.....
and that would let you know that the oil pressure warning light circuit is functioning correctly....
and it is still showing no pressure at idle with the mechanical gauge you are screwing into the stock port on the side of the block correct?
did you use a new gasket where the pickup tube connects to the bottom of the block and torque correctly? you could be leaking inside the pan at this connection a small amount and the oil pump cannot create enough suction at idle to overcome that leak.
then at higher rpm, the leak is overcome and pressure comes up. that is one possible problem.
and since you said its starting to rattle again, you are porbably going to have to go back in for crank bearings again. you can check the gasket then.
also, do you have any plastigauge readings for the bearing clearances for the bearings you pulled out the first time? what about the new ones you installed. standard bearings off the shelf may actually be too loose if your engine is pretty worn. I always check with plastigauge even when putting in new ones to make sure you have the right clearance for oil.. the fsm will tell you what to look for, but i want to say .0025" gap when torqued...IIRC
...edit: also, please tell me you didnt use the liquid form in place gasket for the oil pickup tube?...could have sucked a chunk of overhanging gasket goop into the oil pump...oil pump will have chewed it up into tiny pieces sending it scattered across your lubrication circuit
if i read correctly, you mentioned that a light stays on continuously when you have your mechanical gauge connected right? so i assume you have the light only. not the sr5 gauge.
so it cant be a bad dash gauge.....
and that would let you know that the oil pressure warning light circuit is functioning correctly....and it is still showing no pressure at idle with the mechanical gauge you are screwing into the stock port on the side of the block correct?
did you use a new gasket where the pickup tube connects to the bottom of the block and torque correctly? you could be leaking inside the pan at this connection a small amount and the oil pump cannot create enough suction at idle to overcome that leak.
then at higher rpm, the leak is overcome and pressure comes up. that is one possible problem.
and since you said its starting to rattle again, you are porbably going to have to go back in for crank bearings again. you can check the gasket then.
also, do you have any plastigauge readings for the bearing clearances for the bearings you pulled out the first time? what about the new ones you installed. standard bearings off the shelf may actually be too loose if your engine is pretty worn. I always check with plastigauge even when putting in new ones to make sure you have the right clearance for oil.. the fsm will tell you what to look for, but i want to say .0025" gap when torqued...IIRC
...edit: also, please tell me you didnt use the liquid form in place gasket for the oil pickup tube?...could have sucked a chunk of overhanging gasket goop into the oil pump...oil pump will have chewed it up into tiny pieces sending it scattered across your lubrication circuit
Last edited:
- Thread starter
- #14
did a little in depth research with owner of truck and come to find out this engine was put in appx 3 years ago. Since then 4 cams have gone flat along with rocker arms going bad. This tells me that there has been a oiling issue from this engine from day one three years ago. Other than that I did not do a plasti guage reading and did use a new gasket on pick up tube. My thinking is a air leak on the suction side of the oil pump, however I am unable to confirm that theory because every thing seems to be sealed up. Looking at the possibility now that there is a internal engine issue with this engine.
What about a missing oil galley plug, IIRC there are oil plugs internal to the engine, if one of these are loose or missing that would account for low oil pressure. Someone correct me if I'm wrong but I think there are some on the lower end on or near the crank saddle, perhaps the wrong term, I trying to describe what the crank sits in....perhaps a galley plug, of there are any, on the head. If the engine was rebuilt about three years ago what extent was taken to clean and rebuild the engine, some people will remove the internal plugs, some will not.
Good luck
Good luck
These are the oil plugs I was referring to, these if loose would cause major oil pressure issues.
x2
looks like if you want to save this engine....its coming apart for an investigation
looks like if you want to save this engine....its coming apart for an investigation