Car pukes oil at the filter on start-up (pics)

So, bypassed my wiring trouble this morning and started the car. YEAH!

5 sec later I noticed it was puking tons of oil. The oil pressure had pushed the rubber seal out of the filter and oil pored out. I have a CoolCat spin on filter adapter.

Cleaned up, tried again with a different brand filter. Same thing happened. filter did not un-screw itself I clocked the second one. Unfortunately I’m starting the car next to the engine so I don’t have time to see the oil pressure gauge. I tightened the filter as tight as possible with both hands.

Guy at CoolCat was nice enough to answer the phone when most are on extended holiday. He’s never heard of this problem before. UGH. He suggested I pull the relief valve, I did, looks fine. Of course I would not know good vs bad if I saw it.

Took and oil cooler spin on adapter from previous owner off the car before rebuild. Could he have done something to up the pressure for the cooler?

I have one of the last 3.8’s 6 from the end, and I believe I may have a 4.2 oil pump.

Thoughts?
BrianM

I can’t tell from the photos, but have a look at the end of the pressure relief spring where it goes into the hose nipple. There needs to be a way for the oil to get around the end of the spring and down the bypass hose. I suspect you are blowing the rubber sealing ring from too much pressure. Did someone add shims to the end of the relief valve spring? These could be blocking the bypass flow.

Congrats on getting her fired up, despite the temporary setback.

I’ve had this happen twice, neither engine was a Jaguar. One a 1968 BMW
1600, the other a BMC A series. Was a stuck/sticking pressure relief valve
in both cases; and nothing could be observed on any of the valves or bores
by my naked eye.

Cheers, Alan

Here are some closer pics of the valve assembly.

Looks like there are 3 “cir-clips” stacked. Is that right?

Brian,

I have a Series 2, so the pressure relief valve is different, but that photo of your relief valve looks different from what I see in the vendor’s catalogs. There appear to be a couple of washers added at the RH side between the spring and the end piece that I don’t see in the catalogs. I wonder if they were added to increase the pressure? Hopefully someone familiar with the 3.8 pressure relief valve can comment.

-David

Here’s a pic of the Oil Pressure Relief Valve from my 4.2L E-Type.

By comparison that stack of three washers on your OPRV looks like a “tweak” that someone has added - that would likely raise the pressure at the relief valve and could be your problem.

Hope this helps. :slightly_smiling_face:

Ahhh, Like I said he had a oil cooler added so maybe he saw a drop in pressure so added the stack of washers.
I will see if I can remove them.

Remove the cir clips. Some PO “improvement”. I suspect they are blocking the bypass. The oil pump is constant volume, so if blocked it can generate very high pressures. Enough to blow the gasket for sure.

I didn’t realize that this had an oil cooler at one time. If the cooler was plumbed off the filter head, the internal passage between the center spigot and the return port would have been blocked, so that return oil would be diverted through the cooler circuit. If all you did was block the cooler ports, there would be no passage for oil to enter the block. I will dig out my filter head samples tomorrow and see if I can figure it out.

Here is a picture of the old set-up. Hopefully the bit on the right with the hoses attached did the diverting and nothing was changed internally, other than the stack of washers.

Success!
What I thought were cir-clips were actually stainless steal lock washers stretched and pressed on. I had to carefully cut off the lats two.

Car starts now, no leaks, 40 PSI oil pressure at fast idle. Now to chase down the electrical Gremlins.
Thanks All For your help,
BrianM

Good job!

The sandwich plate diverts to the cooler without mods to the filter base. Just in case anyone in curious, I annotated a photo of the reverse side of the 4.2 filter head.

IMG_4723

Maybe I’m being overly cautious - but - I would be getting a new spring or at the least checking the free length against the specification. Your photo shows a little kink in the spring. I had a Triumph once with low OP - the previous owner had made a similar “spring packing” modification causing the spring to fracture. OP returned to specification with new parts. Paul