Oil light --HELP

[Burgundy8]

Started a new thread for this as my problem has returned....several weeks ago I noticed that my oil light would flicker/flash every 8 seconds when I am at a traffic light. this got worst to the point where it was happening even in Park every 3-4 seconds. I replaced the oil flight switch, did an engine flush, changed the oil at least 4 times and finally changed the oil pump. While I had the front cover off, I also cleaned and changed the o rings for the relief valves. This morning on my way to work the oil light was back, the engine starts and runs fine with no clatter or engine noise but this light is now driving me crazy. Short of making an adapter to check the oil pressure, can you guys think of anything that might be causing this?

Only other issue I have with the truck is a mis-fire on 5 and 7 and the down stream 02 sensor on bank 1 seem to be acting up, I have new plug wires and sensor to replace this weekend but doubt this has anything to do with my oil light issue.

[Scouse]

At this stage, I would be inclined to fit a gauge to see what pressure you actually have & take it from there.

[TheTree]

Hi

Yes I agree a pressure gauge is what you need now

Steve

[benji]

I have to admit being almost at the same stage Burgundy.
After replacing the oil gears, and changing to a thicker oil with a new pressure switch I'm still getting the oil pressure light come on when it's below 600rpm.
Autobarn have oil filter sandwich plates for $70 - I picked one up the other day but havn't put the guage on yet.

If you decide to go through the oil pressure switch is 1/2" UNF (UNO really).

On mine I'm hoping it's a front cover problem as it was very heavily scored in the pump facing which can cause big problems apparently.


Best of luck!

[p38arover]

Autobarn have oil filter sandwich plates for $70 - I picked one up the other day but havn't put the guage on yet.


Picture please!

[Burgundy8]

Thanks for the replies guys.....Benji, thinking back I did notice some minor wear on the front cover but did not think it significant enough to cause this, guess I was wrong, will start there and see what happens. Might plumb a line for a manual gauge while I am there....ugh.

Thanks again guys, will let you know the outcome.

Mike

[benji]

That makes two of us. Talking to dad last night he was saying that any scoring will have a huge effect on the pump. He had the same problem on an early 3.9 (different pump I know), it turned out that there was some scoring on the bottom plate. After that and some new gears it was perfect. My uncle also had the same problem on his 300tdi (same pump I believe). Again it turned out to be scoring on the pump, though it didn't seem to stave the engine of oil and produced good pressure at revs so he just left it. It went for 100'000's km like that - with no smoke.

Here's the fillet sandwich plate. They're made in Melbourne. They also had oil cooler adapters there, and the sales staff didn't know the difference. .....

[p38arover]

Excellent, Benji. Do you have the part no. for the one you bought? Was it specified by oil filter, e.g., suits Ryco Z9?

[Hoges]

On the front cover of my MY2000 Thor 4.6 is a blanked off access port to the oil gallery. It sits below the pressure switch and is plugged with a hex head screw plug. It takes a M12 ( x 1.5mm) thread. Seems ready made to receive a screw-in electrical sender (with appropriate adapter) for an oil pressure gauge ... I discovered it when needing to prime the oil pump after the top end overhaul 18m ago... do the GEMS engines have a similar front cover... if so may preclude need for sandwich plate?

[Keithy P38]

Personal preference here, if I was to fit a backup gauge, it'd be mechanical rather than electric. Will always work when you want it to.

I run two mechanical gauges in my Torana (oil press and water temp).

Cheers
Keithy

[mechanic2you]

Just a few things that can cause low oil pressure on the 4.6

Camshaft bearings
Worn rocker shafts
oil pressure relief valve seating
All these items are associated usually to high mileage and or poor service history
Hope this sheds some light on your problem

[benji]

Unfortunately no such thread on the gems cover. I wonder if a bosch cover would fit the gems setup....?

I havn't got the packaging anymore, but this might help you.

[PhilipA]

Nobody appears to have suggested replacing the oil pressure switch .
seeing thay are only about $30, this would be the first thing I would do.

it is pretty common for them to fail and have the light come on at normal oil pressure.
I have had it happen twice over many years .
Regards Philip A

[chopper]

He said something about replacing the oil flight switch in his first post. That's probably the oil pressure switch.
If the lifters aren't rattling then it must have some oil pressure.
I had a Toyota in the shop the other day that had a smashed in sump and was nearly fully blocking the pick up, strange thing, had light on at idle but went off under revs, just shows that the pump is designed to make good pressure but don't lift/suck very hard .So you might need to check for a partial blockage at the pickup, AFTER you confirm pressures across the board with a gauge .
Could also be dodgy wiring , easy enough to hook up a test light directly to the switch and eliminate any possible issues in the circuit.

[Burgundy8]

Well hope this is the end of this sage....all indications are that after fitting a new oil pump, the front cover had some scaring and I was right back to square one with my flashing oil light. I just finished fitting a new the front oil pump cover (which ironically came complete with all the parts that I bought a couple weeks ago... new oil pump, new oli pressure relief valve and crank shaft oil seal) She is back together now and the drive home was without any issues. Will put some miles on her tomorrow and see what happens.

Mike

[benji]

If you don't mind Mike, would it be possible to pay a photo of the scoring on the oil pump faces?

Where abouts did you get the front cover from?

[Burgundy8]

Benji

Remember I am in the US, got the cover from Atlantic British for about US$400, dealer was asking $600. Haven't figured out how to do photos yet but will give it a try.

Mike

[FANTOM P38]

For anyone thinking of adding pressure gauge another option is to fit "T" piece where oil pressure switch goes ( if theres enough room of course)
may be easier than sandwich plate!

[benji]

Unfortunately there's not a lot of room where the pressure switch is. I've heard of someone making up a house that screws into the block and remote mounted the pressure switch and guage senders etc. But the prices I've got to make up the hose were about $70.