Oil pressure switch spurting oil

Question:
If the plug in the back of the OPS isn't properly attached can oil escape in large amounts?
Should I be looking somewhere else?

What I did:
Two days ago I changed out the OPS (Oil Pressure Switch) on my 01 4.6 because it was 20yo, reading to high and would then stay high for sometime after loading it up through the gears. The new OPS has fixed that issue and it now sits stable at 4 and slightly rises when I lode it up and returns to 4 when cruising.

What happened:
Went for a drive today and after loading up with full throttle to about 4.500 RPM in second and third) for a short time, about a minute later I was cruising home under 2,000 RPM and the check gauge light came on with the audible warning, I immediately pullover and with the smell of oil in the air pop the hood to reveal the plug on the back of the OPS had popped off and there's oil all over, a lot of oil! maybe a 1/2 liter or so, as if it's been spurting from where the plug goes.

I plugged it back in and checked the oil level that looked like it was only just registering on the dipstick and limped home about a mile with no more audible warnings, check engine light on and virtually no oil pressure showing on the gauge.

The engine sounded ok on the way home, It didn't seem to leak with the plug back in and did not heat up more than usual.

CharlesHS said:

putting the part back on that popped off will not cure your problem.

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Thanks for confirming that, I didn't think so. Strange how it stopped leaking on the way home - thank god

CharlesHS said:

I suspect you purchased a knock off Chinese made part from the autoparts store instead of a Mopar OEM part.

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Your right, not a Mopar part. I think it's a local Australian brand but certainly not cheap.
It's a bit a a problem trying to get mopar parts here, it takes ages and ever since COVID many won't deliver to AU.

I'll have a better look at it tomorrow in daylight and see it I can find where its coming from.

GEEP4ME said:

DIsconnect the plug and start the engine. Run it up a bit and see if oil is coming out of the switch.

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Yes! I'll get to that process soon and thanks, to absolutely prove the OPS is the source of the leak I'll need to to that. Nevertheless, at this point the photos are telling a convincing story...


note the block and everything behind the plug is dry

I'm documenting it here - and will continue to until fully solved - as I've never seen one fail through the back, blowing the plug off and then spurting through the back of of it like this one seems to have done. I couldn't find any references to others with an oil pressure switch failing catastrophically, particularly when it's new and a quality product used by most mechanics.

Bursons (local county wide parts supplier) are happy to warranty it, adding they haven't had to warranty that part before and they sell quit a few. They love to say that don't they? but the guy that works there owns three Jeeps and one it a TJ, so there's that.

The only other thing I can think of is that I might have caused it, incorrectly fitting it, so...
After removing the old one I carefully installed it by hand until firm then got out my torque wrench and used it to get a feel for what 20 Nm of torque felt on another bolt, I couldn't use the torque wrench to install it as I dont have the right socket but I think I got the tension close enough and I paid particular attention to not coming into contact with the plastic plug while carefully winding it in, an eighth of a turn at a time.


On another note:
I dont have the same oil to top it up with and it's not registering any oil on the serendipity stick so I'm guessing I'll need over a litre? Keep in mind I just did an oil change last week filling with the SEMI SYNTHETIC pictured below.
I have a full matching synthetic oil but I'm not up with the current technology/dos and don'ts related to mixing them?



My inner hilroy tells me I'm overthinking it but I've just installed a new Golen 4.6 and I want to be sure so my other question is...

(after I've topped it up with FULL SYNTHETIC and run the OPS test to check 100% it's coming out of the connector)

...whether or not I should drop the mixed oil and replace with the semi synthetic oil or can I leave the mixed oil in to the next scheduled oil change?

CharlesHS said:

How many miles are on the engine?

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It's got just over 5,000

CharlesHS said:

In the heat you get in Australia; I would guess the synthetic would provide good heat protection.

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Yeah, you wonder sometimes, they did a study on NYC cabs centered on looking for benefits in synthetic oil and found little but a similar study in Australia found significant benefits from eco to longevity so I use semi syn to have a bet both ways lol

Truth be told I only buy Synthetic it if it's on special, I'm sure It's of little benefit in our tractor engines.

Just ran the OPS test - without the connecter in - to check 100% it's coming out of the back of the connector and yep it's jeeting out at about the volume I do after big night on the boose. I wanted to film it but I just had to shut it right down as its pissng out all over the place.

I've reinstall the old Mopar part and its now stopped leaking and managed to find a website that will ship the Mopar part to AU and ordered it today.