Date:         Wed, 30 Nov 94 08:34:08 CST
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Joel Walker <JWALKER@ua1vm.ua.edu>
Subject:      Re: blow-by to the limit ... what limits?

On Wed, 30 Nov 94 01:25:56 CST Stuart Hutton said:
>Has anyone here actually gone ahead and ignored the wicked blow-by and
>kept adding oil to their diesels?  What is the eventual outcome of
>blow-by?  At what point will the vanagon engine absolutely have to be
>rebuilt?  You might wonder why I'd ask such questions.  Well I would
>almost swear that my blow-by pressure actually turns my oil filler cap.
>Almost, but then again I could always make the same mistake not once, but
>twice...

as i understand it <non-experienced lecture follows>, blow-by allows fuel
to get down past the rings and into the crankcase. now, with diesel fuel,
this is not an explosion hazard, but it does cause what they call
"fuel dilution". that is, the engine oil is now diluted with diesel fuel,
which makes the oil thinner and less able to lubricate properly. so if the
blow-by continues, without frequent oil changes, the whirling and spining
parts of the engine (at least in the areas lubricated by the engine oil)
start to be worn more and more and quicker and quicker.

it's the old "for want of a nail, a shoe was lost; ..." story. if you let
one problem continue, it starts causing other problems to show up.

solution? well ... ring job would cure it. otherwise start changing oil more
frequently to get the fuel dilution out. every month maybe?

joel
<a non-oil-burner, but who listens to the truckers>