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Oil Spraying Air Cleaner

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RAC68

RAC68

Darth Vader
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Hi All,

A friend has recently completed putting a MG TF back together and has run into a problem of having large quantities of oil pushed of the air cleaner’s valve cover vent. We are not talking mist but windshield dripping amounts of oil on a short run.

The previous owner had sent the engine out for a rebuild and it gets 55 lbs of pressure from 20W50 when cold and 25 lbs at idle when warm on a 50 F day. He indicates seeing no vapor coming from the side crankcase vent but was thinking of pulling the plate to see what was behind. He has done a compression test and gets 120 lbs across the board.

Any suggestions?

Ray (64BJ8P1)
 
Strange if it was rebuilt as he was led to believe, meaning the oil return holes in the head should be clear as not to flood the valve cover. Oil pressure not that spectacular, hot or cold. If it's coming out the valve cover vent, that's way too much oil in that area and something is definitely wrong! Bottom line, pull the valve cover and see where that much oil is coming from. Otherwise your just guessing. PJ

Incidentally, My oil pressure in my 1500 <span style="text-decoration: underline">totally rebuilt engine</span> is almost 70 lbs cold and 60 hot and idles at 35!
 
I'd bet the oil separator in the tappet cover is all plugged up.

Commonly NOT cleaned out at rebuild as it should be.

C Ya,
Mark
 
Paul/Mark, thanks for the inputs.

Our plan is to warm up the engine this weekend and take off the valve cover to make sure the valve train is not leaking excessive amounts of oil as it is not clear if it was rebuilt during the engine rebuild. If the valve train proves good, we will then dismount the side cover and check out the oil separator. Since it doesn't appear that the crank vent is producing any vapor when the engine is hot, I'm inclined to think Mark may have nailed it.

Paul, the previous owner installed a pressure adjusting unit on the pump and, initially, the engine had registered 90 lbs cold on an external gauge. The pressure was dialed back to 55 lbs cold and it was thought this would resolve the issue. I interpret your input to indicate the engine can take quite a bit of oil pressure and not transfer excessive amounts of oil on the head to cause this problem.

All the best,
Ray (64BJ8P1)
 
"Our plan is to warm up the engine this weekend and take off the valve cover to make sure the valve train is not leaking excessive amounts of oil as it is not clear if it was rebuilt during the engine rebuild."

You don't want to remove the rocker cover on a T series engine when it is running. Even with moderate oil pressure, each rocker will squirt a stream of oil several feet high - this is normal for the XPAG/XPEG engines. I would suspect that the breather tube off the tappet chest cover is blocked, causing excessive pressure to be vented through the rocker cover vent into the front carburetor air filter.
Cheers,
 
I don't know this as fact, but when my engine was rebuilt, they might have put a new spring in the pressure regulator, giving a higher reading as I thought 60 lbs cold was normal. Mine is not the adjustable kind. PJ
 
Dave/Paul, thanks for the info and warning. I would never have expected that the TF would have normally that much oil squirting out of the valve train or pressure that high. We will forgo running the TF without a valve cover and focus on seeing if the breather pipe needs cleaning.

Again, I really appreciate the information as I am a real neophyte when it comes to the T.

All the best,
Ray (64BJ8P1)
 
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