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High oil pressure and this puddle...

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SMGoose

SMGoose

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I recently changed the oil and filter, cleaned out the sump and changed the gasket, and put in 20w50 oil. The oil pressure is now at 100 at startup but goes down to about 60-70 after a bit of warming up. Then there this:

IMG_0576.jpg

The thick brown puddle next to the coolant is worrisome and appears to be coming from the rear engine seal area. My first step will be to adjust the oil pressure release valve, but I'm worried about where this sludge is coming from. Do you think it's due to the increased pressure? I don't seem to have any head gasket symptoms, but I was planning on doing a test for combustion gas just to be sure. Thoughts?
 
If the oil leak is due to the high oil pressure it would indicate that you have some major opening in the pressurized syste. This would have to be something like a missing or loose oil galley plug. High oil pressure by itself is not going to come out through seals as the block is not pressurized by the oil pump. However, if you have something like a failed valve cover gasket, the supply to the top of the engine can spill out and easily run down the block. Severe blow by from a worn engine can also cause oil leaks, these being through the seals.

My suggestion would be to go to the parts store and buy a small vial of the UV dye that you can add to engine oil. While there buy more oil and some engine degreaser. Completely clean the engine and surrounding areas. Add the dye and make-up oil to the engine and at dusk idle the engine to operating temperature. Use a blacklight (available from the home center) to illuminate the engine. The dye will glow and indicate where the leak is.
 
I will do that to try and pinpoint the leak, although I'm more worried about the color and consistency of it.
As for the oil pressure, this is my first oil change since I bought the car and the engine was supposedly rebuilt not that long ago. Do you think the 20w50 is too thick?
 
I believe 20W50 is "right" for most British cars of the 1960s. It is all I have ever used.

Sorry, I cannot offer any comments on the consistency/color of what's leaking but I agree it is unusual.
 
I've seen oil get that muddy brown color when coolant gets mixed in with it.
 
It's an emulsion. Something, probably pressure, forced the 2 liquids to combine. Oil and coolant would be my guess, but how and where it happened ?
 
Having very recent experience with coolant mixed with oil, I can say that my first reaction to the photo was that you had water in your oil. It creates a mayonnaise consistency in your oil pan (and in your rocker cover, if you run long enough).

Pat
 
Those are the possibilities I'm more worried about. Although I don't see any signs on the dipstick. I do get a little bit of moist carbon spitting out of the exhaust at startup, but it goes away when warm. I still haven't gotten to the parts store, but I pulled the spark plugs and they look like this (1-4, left to right):
IMG_0579.jpg

Those plugs probably have about 20 miles on them after a full tune-up and some carb work.
 
It does look like a water/oil emulsion. Where it came from? Who knows. Drive a bit and see if it comes back before starting to worry. Could have been from a disconnected valve cover line that drained off or something like that.
 
Try a different oil. 10w40 or a straight weight. Not sure what the factory recommended so if you have the owners manual see what it says. Then but your dye in but also re-torque the head bolts when the engine is hot.
 
Forgot to mention that do you have any information on the rebuild? If there was some performance built into the motor then the re- builder could have installed a high pressure or high volume oil pump. That could account for the added pressure.
 
I think the oil pressure is ok, just a healthy pump which a lot of engines don't have anymore...

Mine does the same, after a long drive the pressure will settle down more. It is surprising how long oil takes to get up to temp, especially the heavier weights. The water temp and oil temp take very different lengths of time to get up to their operating temps.

The plugs look pretty good too for a starting point, nothing I would be worried about.
 
Check one of the repair manuals for oil viscosity recommendation, but 50 is too viscous in any case and 100 psi is way too much. The OPRV is supposed to let go at 70, I believe (also specified in repair manuals)Bob
 
Looks like #1 plug is either running rich or has some blow by. Is it powdery or wet?
Is there any of this sludge in the oil pan ? If that's the case you have some other issues
that need to be addressed.
Harry
 
I read a LOT of threads like that one trying to pick the right oil. I think 20w50 should be fine, but maybe not with my setup.

Not sure I have a crankcase breathing pipe. Just a 4, not a 4a. I have a vented valve cover.

Harry, when I pulled the oil pan, during the oil change, there was no sludge like this. That's why I'm thinking the pressure and sludge are related. Could it also be that the coolant and oil are leaking separately and mixing on the ground? Seems unlikely, but hey...
Also, the plug is powdery. Suggests rich, right? Why would only the #1 be rich?

I haven't been able to do much testing on the car this week. I tried to get a head gasket tester (the one you stick over the coolant reservoir and turns the liquid green) but NAPA and Autozone didn't have any. Will try other places tomorrow.

The OPRV is indeed 70. However, it seems as though my adjusting screw isn't stock:
IMG_0581.jpg
It's supposed to be adjustable but mine has a hex lead-welded on. The Big 3 don't seem to stock them either.
 
I think what you are looking at, that looks like a weld, is the lead wire that is used as a seal.
A little heat should free that hex locknut.
Merlin
 
Oooh ok. I give that a shot. What should I use instead to seal it? Felt washer?
 
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