My 72 Europa SS

[Sofa King]

It took a very easy 7 hours. Took my time and worked carefully. It should actually take less time to put it back in.
I couldn’t agree more with hoping I find something obviously wrong! I don’t want to throw new parts on just to replace good parts and find out I still have the problem! I wish that I had the ability to run the engine out of the car. I could probably rig a stand to hold it, but I don’t have a spare wiring harness to run it.

[jbcollier]

You can spin up an engine with just the starter, plugs out, to check oil issues.  I have done it lots of times.

[Sofa King]

Great! I was wondering about that! That will show if my initial oil pressure is better. My biggest problem / frustration is that it looses pressure as the engine gets warm.

[BDA]

I think you should find the oil pressure by spinning in on the starter before you change anything to use as a comparison.

[Rosco5000]

Is it using the original GM/Chev sensor for oil pressure?  My 6.2L is doing the same thing in my Escalade.  Pretty sure it is a sensor though they are known to leak and cause issues.

[Sofa King]

BDA- Good idea.
Rosco- I’ve used both an electric gauge and a mechanical gauge, same result.

[rascott]

i have experienced this, in the past, as a faulty pressure relief valve.
not lotus, but …….
is there one in the oil pump? piston may be stuck in the "cold oil/high pressure" position.
mabe

[Sofa King]

Yes there is a pressure relief valve in the pump, and there is a good chance that is the problem. Unfortunately, the engine had to come out to get to the valve spring. No matter what my problem turns out to be, I am going to swap to a better quality, high pressure pump.

[Sofa King]

The engine will go back in tomorrow! I’m pretty sure that I found the problem. The cam retainer has an o-ring built into it. Not realizing that it seals the main oil passages, I reused the old one. There was no seal left when I took it off the block. There was obviously oil leaking past the seal. Everything else looked good. I added a high pressure pump just to be safe. I’ll see if I can read the oil pressure spinning it with the starter, and start putting it back in the car.
The Hit Rod Magazine “Power Tour” ends about 45 minutes from me this Friday, and I shooting to have it done for that show.

[BDA]

It sounds like you found the culprit and the high pressure pump should ensure the problem is resolved! I'm glad to hear that and I'm crossing my fingers that you make the "Power Tour!" 

Don't forget to give us a full report!

[Sofa King]

Engine went back in easier than it came out! Spent about 3.5 hours on it today. All that is left for tomorrow is bleeding the clutch, connecting and burping the coolant lines, and installing the exhaust. (The clutch bleeder is under the exhaust.)

[BDA]

Boy, that was quick!!! 

[Sofa King]

Progress was a little slower today. The radiator hoses that connect to the front of the engine are a major pain! The engine is very close to the rear firewall at that point and the fittings and hoses have to be attached in a specific order and orientation. But I did manage to get them back in place. Here is a close up of the connected hoses.

[Sofa King]

It’s alive! (Again) I still need to “burp” the coolant and put the seats back in, but I ran out of steam for today!
Oil pressure looks great, but I still haven’t gotten it up to temperature.

[BDA]

Great news!