Can anyone tell me where the oil pump pressure relief valve is on the 1fz engine?
Oil pump relief valve (1 Viewer)
- Thread starter Cruisermudpig
- Start date
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Here's a photo looking up from below: it's under large hex plug
closest to the alternator belts facing up in the photo:
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Another discussion:
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Welcome to MUD!!!
closest to the alternator belts facing up in the photo:
Here's a discussion:
oil pressure and destruction
Hello and goodday: I found my problem and why my I lost oil pressure. I have never replace a oil pressure relief spring in my long years rebuilding engines and will now do it until I can get a spring tester. I have for a long time seen my pressure drop when I hit 3500-3800 and with my old...
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Oil pump for 1FZ-FE
Hi guys! I have a problem with my 1FZ-FE 4.5L it has stage 4 cams with big valves, 100mm pistons, custom long tube headers and custom air filter intake. Boarding and polish for cylinder head, intake manifold and 90mm throttle body. also Haltech Platinum Sport 1000. my problem is that the oil...
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Welcome to MUD!!!
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- Thread starter
- #3
So the one I've circled?Here's a photo looking up from below: it's under large hex plug
closest to the alternator belts facing up in the photo:
View attachment 2389031
Here's a discussion:
oil pressure and destruction
Hello and goodday: I found my problem and why my I lost oil pressure. I have never replace a oil pressure relief spring in my long years rebuilding engines and will now do it until I can get a spring tester. I have for a long time seen my pressure drop when I hit 3500-3800 and with my old...
Another discussion:
Oil pump for 1FZ-FE
Hi guys! I have a problem with my 1FZ-FE 4.5L it has stage 4 cams with big valves, 100mm pistons, custom long tube headers and custom air filter intake. Boarding and polish for cylinder head, intake manifold and 90mm throttle body. also Haltech Platinum Sport 1000. my problem is that the oil...
Welcome to MUD!!!
- Thread starter
- #5
Thanks heaps
It appears he has multiple leaks. The relief valve is not typically one of them.
Yep the main actually looks pretty dry but yes could be anything, dist. O-ring, oil pump cover… Was just wondering if they ever leak.
So I'm going to revive this old thread a little...
What about the second oil pressure relief valve on the oil cooler on the other side of the block?
Are these two valves identical in terms of the parts (spring, valve piston, washer, etc)?
Can either one of these valves cause a low oil pressure problem on a 1FZ-FE engine?
The reason I ask is that last year I had a shop do a head gasket job, in the process I asked them to remove and clean the oil cooler. Ever since the head job I have had low oil pressure, like it hits around 30 psi when the oil is cold, but once warmed up never exceeds about 7psi (tested with an external mechanical gauge attached with a 'T' at the regular oil pressure sensor location. So, I am now curious if some gunk as a result of messing with the oil cooler might have gotten into one of the relief valves and cause it to become stuck open and not build pressure.
IF those numbers are at 'idle' you don't have anything to be concerned about.
It's been nearly a year since the shop did the head gasket, and wasn't until about 5 months after the head job that I noticed the low oil on a long hot drive through CA Central Valley. This is not a daily driver vehicle, except for a quick drive every other week or so to keep things working.
I typically run Valvoline Advanced Full Synthetic 5W-30 oil and Fram Ultra Synthetic XG3614 oil filter. The shop replaced the oil after the head job with some unknown synthetic blend and no name filter; which I figured was fine to flush out any debris introduced by the work they did. Upon noticing the low oil pressure I pulled into the next town and had the oil changed, and bumped it to 10W-30 synthetic blend and new no name filter...
I have not brought the issue of low oil pressure up with the shop as I wasn't particularly pleased with the quality of work they did on the head gasket anyway and would just as soon not go back to them again.
Prior to the head gasket going the only symptoms were rough idle on startup until hot, and eventually overheating mildly, at which time I also could see some bubbles appearing in the radiator; not a lot, just a good sized bloop every 30 seconds or so. I didn't bother with testing the coolant for exhaust gas contamination. No water contamination of the oil was apparent at all.
RPM wise I'm getting around 4psi at idle of around 800 RPM and maybe 7psi at 2500-3000 RPM...
Interesting question... No reason it shouldn't be, aside from using it to crank the to TDC there's no reason it would have been touched or loosened for the head job, but I have never checked it. Why would the crank bolt affect oil pressure though?
Lots of documented problems with wix filters and lots of no name filters are made by wix.
Maybe throw an oem filter on the rig and see if it makes a difference.
Maybe throw an oem filter on the rig and see if it makes a difference.
Friction only is what runs your pump. So IF the crank bolt is loose....it could be the cause of the low oil pressure. But if you have 7 psi at anything off of idle...something is amiss alright. Mine is 55-60 psi at 2500 rpm.
Ditto all the above: toss the no-name filter immediately, install a Toyota filter. Might not be the cause but a few people have had their engines ruined by crap filters.
Has the crank bolt/harmonic balancer ever been removed (ie: to fix an oil pump cover leak )??
Has the crank bolt/harmonic balancer ever been removed (ie: to fix an oil pump cover leak )??
Yes, the balancer was clearly moved once upon a time by one of the previous owners, only evident by the replacement screws on the oil pump cover that are now Allen heads in lieu of the original JIS screws... And the fact that the oil pump cover is very clean... But the oil pump is driven internally, how can the harmonic balancer possibly affect oil pump operation?
I have ordered some Toyota 90915-YZZD3 filters as well as all of the parts to rebuild the oil pump and oil cooler relief valves. Hopefully all of that will resolve the low pressure. I'll start with the filter and report back with results / changes.
As mentioned above by flintknapper, the large 30mm crank bolt that holds the harmonic balancer on also "squeezes" a gear behind it (in line on the crankshaft) that is not keyed, and that gear drives the oil pump gear. So if your harmonic balancer bolt is not torqued correctly (to ~305 ftlbs) then the gear behind it might slip and if that happens you can lose oil pressure.
If you're still driving the vehicle maybe switch to a higher viscosity oil for now to see if it helps. Many people use 10/15W-40 if the outside temp is not too low for it.
If you're still driving the vehicle maybe switch to a higher viscosity oil for now to see if it helps. Many people use 10/15W-40 if the outside temp is not too low for it.
