Mechanical Oil Pressure 1fz-fe (1 Viewer)

[OffGridOverland]

So I have the Toyota lazy oil gauge.

This has only been a issue since I had the headgasket redone.

At the time they replaced:
Timing chain
Guides
Tensioner
Resealed the oil pump
Front main seal

Toyota OEM headgasket
ARP headstuds

Before my oil gauge was always middle and just always was happy.
I installed a Autometer oil pressure gauge. And well the results are showing low oil pressure.

I read some say the lazy oem gauge is normal. But since I am running both gauges now at the same place. Two different sending units. They seem to match the results.
I'm now concerned about this.

@ idle


@2500 rpm


When cold it runs higher pressure at start up. I've seen 45-50psi

I am running Shell 15/40 oil. All my previous vehicles love it. I've had the oil changed 3 times now.
So I'm at a loss on what to do here. I do not drive it and I'm $1700 in the hole for the repairs.

Anyone have any ideas?

 

[baldilocks]

What sort of pressure would you like to see? I'm no 1FZ expert but I have read that in general your good with 10psi per 1000rpm. You are inside these parameters.

 

[OffGridOverland]

I'm under that at idle. And per my manual. I'm low across the range. Worse when it's above 75° outside.

I haven't built a 1fz yet. But I've built a lot of other motors.
We always run higher oil pressure.
Course the clearance are different.

 

[Kernal]

What year is your FZJ80?

 

[OffGridOverland]

It's a 97, and I forgot to mention I did check and retorque the pulley bolt To 309lb

 

[baldilocks]

I am very interested in this thread and wish I had more experience with this. if the shop removed the head it's possible they deemed it necessary to change the oil as a precautionary measure and put lighter weight oil in like the book calls for. BTW I run a 15/40 myself.

 

[FloridaFJ80]

It seems to be about right.. I wouldnt worry..

 

[inkpot]

What year is your FZJ80?

And how many miles?

 

[OffGridOverland]

I have 197k

 

[VuickB6]

I know I'm a little late to the party but I found this while doing some searching on oil pressure. One thing you should do is switch to an electric oil pressure gauge. Running a line full of hot pressurized oil in to the cab is never a good idea.

 

[OffGridOverland]

This is what happened a few thousand miles later. I am building the motor now. Not going to go with a stock OEM oil pump. I'm going to mod mine for more PSI.
This was the mains 4 thru 7

 

[NW Wheeler]

Really sorry to see that, now you have me wondering about my oil pressure. I am interested seeing a picture of the stock oil pressure gauge at various pressures compared with a gauge that has numbered graduations or a digital readout. Or is the stock gauge accurate enough to say the first mark is XX?

 

[Rifleman]

By looking at those bearings and the low oil pressure your reporting i would say one of two things happened. Number one, a failure of the oil pump to provide sufficient oil pressure due to excess clearance between the fixed and driven oil pump rotors or end plate caused by wear. Number two, a piece of crap got stuck between the oil pump relief valve and it's seat, causing the relief valve to stick part way open, allowing oil to bypass the pump, thus causing the pump to provide insufficient oil pressure to the bearings. In both these cases you would still have oil pressure, just not enough pressure to protect your bearings from making metal to metal contact.

 

[NW Wheeler]

Oil pressure gauge seemed to be reading lower than in the past, leaving on a 3000 mile trip to the CruiserFest, couldn't stand it any longer, bought a test kit at HF. 182,549 miles.

Tested oil pressure. Engine Temperature: 185˚. Adaptor: 1/8” 28 BSPT elbow. Very happy with the results , new oil pressure sending unit on the way.
FSM Specs warm: Idle: 4.3+, 3000 RPM: 36 - 71 PSI .
RPM PSI
600 17
1000 35
1500 40
2000 55
2500 62
3000 67

 

[cybrstar]

I just had to ask because now I’m seeing the same symptoms in my LC. Did the same as OP headgasket, timing chain, guides resealed oil pump, ect. Before the rebuild had great oil pressure, after rebuild oil pressure took a dump. I did check and replaced the oil pressure valve and the oil filter with no luck. I’m thinking it’s having to do with removing and resealing the timing chain cover. Maybe hairline gap? Any other suggestions?