From: "Marvin Kaye" <marv@lancaironline.net>
Subject: Re: [LML] Re: Legacy IO550 fuel injection system vent hose/oil
 mist
To: lml
Date: Thu, 12 Feb 2004 08:42:07 -0500
Message-ID: <web-2988811@logan.com>
In-Reply-To: <011201c3f119$772bc720$be316644@S0030046211>
MIME-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"; format="flowed"
Content-Transfer-Encoding: 8bit

Posted for "nkanagy" <nkanagy@cox.net>:

I have heard that many (I believe particulary round) engines that operated
in cold temperatures used to have a "oil dilution" control that was
activated for a determined period of time before engine shut-down. The
purpose of this system was to intentionally inject fuel into the oil while
the engine was running and lower the oils viscosity. Then, upon startup
(some time later and at quite a bit lower engine temp)  the oil was not as
thick and the would do a better job of lubricating the engine. The fuel
would evaporate in a few minutes and exit via the breather, leaving the now
warmed up engine to operate with oil at its normal viscocity.

If engines used to be equipped with this for intentional use, how could a
little bit of vapor cause any harm?


> and gums up the belly (the plane's, not mine). My A&P says the tube vents
fuel
> injection system overload, during priming, and washes some oil off the
engine
> innards. I suggested routing the hose into the crankcase vent hose, thence
> through the oil/air separator. My A&P voiced disapproval of introducing
the
> fuel (vapors only, I suspect) into the oil by return to the engine.
>
> I'd appreciate the group's guidance.                Wendell Durr
>
> [ you want a snuffle valve... its a small reservoir with a ball barring
>   that will flow when inflight but will hold some priming gas on the
>   ground... photo attached. -Rob ]