From digest.v6.n753 Tue Jun 10 06:53:12 1997
From: Richard Cartiledge <richard.cartledge_at_jigsawsystems.co.uk>
Date: 10 Jun 97 10:17:54 +0100
Subject: re>Oil deposits? BLACK DEATH
re>Oil deposits? BLACK DEATH
ngh at MIT.EDU Nicolas Hadjiconstantinou. wrote......
When I removed the valve cover
I was faced with a horrible sight.
Everything was extremely dirty. Everything
is mat black, with the sole exception of
the camshaft lobes! In addition to that
everything that does not move has at least
1mm of black deposits on it. This is
particularly true in the exhast side of the
valves. The deposit is no substance I could
recognize. It looks carbonacious, and it is
solid, but it is also wet and can be
sheared very easily.
***This sounds like the black death, (popular in the 80's when the higher
temperature in engines was breaking the oil down into carbon sludge.
Has anybody seen this before? Is it normal?
What do you think about oil additives that
clean the engine internally? I am afraid
that at this stage using these additives
will just make this big chucks move around
and possibly block something....
- Whatever oil has been used has probably been inferior or left in too
long or both.
I'm no expert, but if I was in the same boat, I'd wipe as much up onto some
lint-free cloth and remove the oil drain plug whilst the engine is hot. Get
a no-loss bristle brush and some Jizer or Gunk and clean up the head and
spray-bar - let the mess wash down into the sump and out of the drain plug,
when the sludge is all loose, pour 1/2 - 1 gallon of Jizer/Gunk/Paraffin
over the valves to wash it down followed by a gallon of that really cheapo
oil you get for 2.99 just to remove the cleaner reidue.
I'd then put a new filter and fill up with good quality brand-name mineral
oil and change it and the filter after 1000-2000miles. Check the valvegear
again, if it looks cleaner, consider changing to Synthetic (which is much
cleaner), if not continue with good mineral oil for a while.
If you find the problem reocurrs, you may have exhaust gas blow-by which
could be the velve stem guides.
Good look, Richard (Shiny valves - shing boots - shiny mind)
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