Hmmm, has this motor . . .at any time since and including it's last build
or "freshening", exhibited a problem with "ring-seating"? Excessive
"blow-by" or low compression pressures in a fresh-built engine? The reason
I mention this is that it is not unknown for a unlearned and/or unscrupulous
person seeking a quick-fix, to "feed" the air intakes a small amount of
"Bon-Ami", a white, mild abrasive cleansing powder, in order to break the
glaze on cylinder walls. I have even heard of the practice being
recommended in a manufacturers factory service bulletin back during the
early days of chrome rings which had seating problems; I can't vouch for
this being true . . .I hope it's NOT true, but you might consider the
possibilities. Also, if there has been a dry fire extinguisher discharged
in the engine area while it's running, I seem to remember that some
extinguishing media can be very abrasive. I wouldn't think the contaminant
was oil-born or the bearing and sump would show evidence. Keep us informed.
Tony
>OK- this may be open the doors to a whole new series of jokes, for which
>you are all welcome in advance, but wondered if anyone could shed some
>light on the following:
>
>At Savannah over the Easter weekend, just in time for the feature race, the
>engine on my Lola T294, a Hart 420R, refused to start. In earlier
>sessions, it ran OK, though it sounded a wee bit off-song to me (no one
>else thought so), and felt perhaps a bit down on power, but nothing
>dramatic. Then, it was hard to start for the pre-race warm-up, but
>ultimately did start, and warmed-up fine. When I got in the car to start
>it and go to the grid, it refused to fire.
>
>Checking compression showed compression down - and from memory, almost nil,
> on all cylinders. End of weekend. Sent the motor off to Dave Vegher who
>told me yesterday, that upon opening it up, he found a white powdery
>deposit "caked" on the rings...said it looked like flour... And the radii
>on the edges of the rings themselves has been as if removed to sharp edges.
> And the rings just "popped" right off the pistons, as if the pistons had
>shrunk... but they hadn't.
>
>Dave said he's never seen anything like it. There is no evidence of
>overheating or excessive piston temperature, all bearings are in great
>shape. He asked me if I made any enemies at Savannah or Sebring, because it
>was as if something had been added to my fuel or oil. Despite that I can't
>imagine anyone in vintage racing doing such a thing, there is nothing in
>the fuel filter, metering unit, injectors, etc. Which leaves the
>possibility of oil or air, or???
>
>Dave discarded all the white stuff... else it would have been interesting
>to have it analyzed... but lacking that evidence, does anyone have any
>clues on this?
>
>Sorry for the length of this letter.
>
>-Alfred Kobacker
>
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