I would think the split would be more like 99-1 in favour of 'crazy'.
However my father did tell me of two tales that would be relevant here and
one just because its kind of connected.
The first related to a motorist shortly after WW2 when money, cars and
spares were tight. He knocked out a big end - was able to get some shells,
but without the time/money to strip the motor and do it properly, he filed
the offending crank pin down the .010" - restoring its roundness. This was
done lying on his back with the engine in situ with some careful (but
awkward) measurements with a micrometer.
The second tale relates to an army crew in the desert who ran a big end. As
they were miles from their base and it was clattering like hell they dropped
the sump and replaced the bearing shells with a section cut from a leather
belt. The engine ran quietly and they got home, but later got into trouble
as the soft leather had absorbed some of the inevitable bits in the oil
which made a very effective lapping tool thus wearing the crank way below
its regrind sizes.
The third (less relevant) tale was from the same army group. One of their
other trucks had a rather tired engine, but it was decreed that it could
carry on for a bit. So the oil was drained out, the engine run until it
seized, and then the oil poured back in to conceal the evidence. 'Oh dear!
my engine's seized - I'll have to have a new one!'
Neil
----- Original Message -----
From: <Eganb@aol.com>
To: <Triumphs@autox.team.net>; <british-cars@autox.team.net>;
<tr8@mercury.lcs.mit.edu>
Sent: Thursday, September 28, 2000 4:52 AM
Subject: Decision on TR7 Bearings from Hell
> Well, with the posting of this email, half of you will think i have lost
my
> mind, and the other half will be saying "go for it!"
>
> After a closer look at the scratches and burr on my TR7s crankshaft, I'm
> going to rely on my trusty Dremel and yards of Crocus cloth to smooth out
> these blemishes caused by my carelessness, instead of pulling the crank
which
> I have neither appropriate space or cash to do, but would probably end up
> being a heck of a lot quicker.
>
> What I do have is plenty of time and sweat-equity to put into the project,
> and for you who are still interested, a couple of additional questions:
>
> 1. I finally got the #1 bearing out by taking the camshaft caps off and
> raising it enough to reduce the chain tension. The upper bearing slid
right
> out. My question is whether the chain is suppose to be so bloody tight,
and
> is there an adjustment I should be looking for?
>
> 2. My strategy is to clean up all the scratches and burrs, then spray a
> couple of gallons of WD40 over everything to clean out any grit, then put
in
> some extra new shells on the bearings that were scratched, turn the engine
> over several times by hand, and then take the caps off again to see if any
> scratches appear on the shells. What do you think?
>
> 3. After I reassemble everything, including brand new bearing shells, I
> thought I would leave the sparkplugs out, and pull the car in gear to help
> the engine get "broken in" without the heat and pressure of actually
running.
> Maybe pull it for a couple of miles, then replace the oil and filter.
But
> then I thought maybe this would cause accelerated wear because the engine
> wouldn't be running at its normal temperature, so the oil might not be as
> fluid. Thoughts?
>
> After re-reading all of the above, I can't believe the effort I am about
to
> go through. But there's something about the challenge that is irrestible.
>
> Of course, just to be safe, anybody got a spare crank they don't need?
>
> Again, many thanks for all the comments and advice.
>
> Bruce
> 1980 Inca Yellow TR7 5-speed convertible
> Chapel Hill, NC
>
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