Subject: Re: [TR] Triumphs Digest, Vol 6, Issue 176

From: [email-masked]
Date: Thu, 23 May 2013 17:21:00 +0000 (UTC)

Johnnie,

I don't think it has anything to do with the head. Leaky valve guides and
valve problems would cause pressure noted the outside of the engine, not to
the inside. Intake valve guides which leak would suck in some oil from the top
of the head and cause smoke up the exhaust, but would not pressurize the
crankcase.

Your description of the problem would appear to be excessive pressure in the
crankcase. This would be caused by in adequate PCV ventilation, or excessive
blow-by of the pistons overcoming the capability of normal PCV ventilation. I
cannot come up with any other mechanism that would pressurize the crankcase .

I do not know how to be sure about piston blow-by, especially if it is
occurring on all pistons equally. Others here would be able to answer this
question better than I. If the problem isB effective PCV ventilation then the
most expedient solution is to revert back to the earlier road draft tube
ventilation design. To protect the environment you might use a catch tank but
another solution is to use a longer vertical length on the road draft tube so
that less oil remains suspended in the air as it exits the road draft tube.

On a Spitfire engine that had unbelievable blow-by, I could feel pulses of air
exiting the oil filler hole when the cap was removed. Do you notice anything
similar?

-Tony

----- Original Message -----

Message: 5
Date: Wed, 22 May 2013 20:02:56 -0700
From: "John & Pat Donnelly" < [email-masked] >
To: "'Irv Korey'" < [email-masked] >, < [email-masked] >
Subject: Re: [TR] Bad Engine Oil Leak

Hi Irv,

Something's wrong here, and I don't believe that venting to a catch tank is
the proper thing to do. The real issue in my mind is, what's changed? and
how do I validate it?

My first thought was that the PVC value wasn't working properly, but I got a
new diaphragm from Moss, and then a whole new PCV value, and neither was it.

The leak has been progressively getting worse. I'm now thinking the valve
guides are leaking.

B 

Johnnie

'67 TR4A

** [email-masked] **

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