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Wedge TRy crankcase pressure

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johnrip

johnrip

Jedi Hopeful
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I had my TR7 engine rebuilt 5 years ago. It is USA spec, and I removed the air pump and disconnected the EGR piping. Ran great since then, and had no oil leaks (what a pleasure). Recently, after 5000 or so miles, I stated having to work on several oil leaks. Fuel pump seal, rocker oil filler cap, even once some small amount came up through dipstick tube. Lately, my spin on fuel filter adapter is leaking badly. So here is my question:
1-Could the spin on filter's small seal be non-seated, so that the oil is bypassing the filter and causing an increase in oil pressure around the adapter?
2-Is my oil pump spring stuck or is it causing too high oil pressure? (I can not check this myself, I will have my mechanic check pressure)
3-Could this be crankcase emission pressure? All piping and carbon canisters are in place?
Any ideas? I am going to reinstall the old oil canister this week, and see if that solves the leak...but I feel more is going on. I would like to solve this before I store the car for the winter. Any ideas will be appreciated...thanks JOHN
 
Sounds like crankcase pressure to me..excessive pressure..Make sure that the plumbing is not only in place but open and non restrictive.
 
I agree. The fuel pump, cam cover cap and dipstick are all not exposed to oil pressure; so there is no way to blame those leaks on high oil pressure. Plus the oil pressure relief valve is built into the pump, so there is no way for the filter to allow "too much" oil into the rest of the engine.

As Ken said, check the vent lines to be sure they are not collapsed or kinked. They should be OK after just 5 years, but it's possible someone mistakenly used the wrong kind of hose. OEM quality hoses should be replaced every 10 years or so anyway. The carbon canister is also supposed to be replaced periodically. No one ever does, but it wouldn't hurt to check that it still flows freely. I've seen them clogged with dirt and rust to where they won't flow at all.
 
Thanks to both of you..I have checked all the lines, they are connected as the diagram shows, and I have 'blown' air through all of them. How about the manifold line, that connects to the anti run on valve. I am not sure the valve is working? Is there another cause of too much crankcase pressure?
 
johnrip said:
Thanks to both of you..I have checked all the lines, they are connected as the diagram shows, and I have 'blown' air through all of them. How about the manifold line, that connects to the anti run on valve. I am not sure the valve is working? Is there another cause of too much crankcase pressure?
Click to expand...

The lines need to be open for the full diameter, you might not notice if one was partially collapsed just by blowing through. The vacuum line to the ARS is not part of the crankcase vent, so it's not your problem. And the ARS should only activate right after you turn the key off (while the engine still has oil pressure), so it isn't going to be part of the problem either.

Unfortunately, the other cause of too much crankcase pressure is excessive leakage past the rings; either because they are worn out, or a damaged cylinder wall, etc. It's not at all unusual to have an engine that runs just fine, but is losing a lot of exhaust past the rings.
 
I don't see the ARV having any influence on crankcase pressure.
You might need a helper to determine if it's working.
When the engine is cold and the oil is thick..start the engine and let it run about 1 minute. Then as you stand near the Carbon Canister, have someone turn the ignition key to "OFF". The engine will die of course, but within seconds the residual oil pressure will drop. It is then you will hear the click of the solenoid valve in the ARV.
They work like this:
https://www.mv.com/ipusers/last/emissions/page_52.html
 
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