[Spridgets] 1275 Rod Knock Update

[GUY DAY]

Michael,
I'll never forget when in much younger days I was allowed to re-build a 
1275 Mini engine for my Rolls Royce apprenticed friend to power one of 
the Mini pick-ups he used for his business.  The engine had been for a 
re-bore, crank grind, balance etc and I had done a bit of gas flow work 
on the head.  Not a super hot racer but a more efficient mini delivery 
truck.  It seemed to re-build fine but when it came to firing it up, it 
ran, but the oil pressure would not rise.  My friend cursed me up hill 
and down dale saying amongst other things, if you want a job doing, do 
it yourself.  I felt awful and didn't see him for a couple of days but, 
when I did, I raised the engine problem to see what I had done wrong. 
He couldn't get oil pressure up either (yeah!) and when stripped down 
and checked over yet again, it was found each of the bearing surfaces on 
the crank was tapered!  Even now, now that I've slept a few times since 
then, I still cannot work out how the grinding on the crank could have 
been done like that.  The firm that did it had one of the best 
reputations in that part of Northern England in those days and should 
have realised if their machinery wasn't correctly set.  My friend 
forgave me and let me play with more of his motors so I knew I was truly 
forgiven, but I like to think that made me a slightly better (but 
pedantic) spanner man.  When you strip your engine down again remember - 
you did it right - check the work others did.  Others who perhaps don't 
have the love of your engine that you do!
Keep the faith!
Guy R Day

------ Original Message ------
From: "Michael MacLean via Spridgets" <spridgets at autox.team.net>
To: "Spridgets" <spridgets at autox.team.net>
Sent: Thursday, 4 May, 23 At 10:14
Subject: [Spridgets] 1275 Rod Knock Update

Took compression readings of the 1275 engine in my Bugeye as the start 
of the rod knock diagnosis.  Not good.  No 1 was 110 psi, No 2  -  90 
psi, No 3 - 80 psi and No 4 was 110 psi.  Which means none of them are 
up to snuff.  Also found the spark plug wire for number 3 cylinder had 
fallen out if the distributor.  I plugged it back in and started the 
engine.  It idled smoother, but under acceleration the knock was still 
there and definitely coming from the block.  All this with only 3 - 4 
thousand miles since the swap from 948 to 1275.  Next will be the oil in 
the cylinders and retake the compression test to see if the low 
compression is due to the valves.  Might as well figure a head rebuild 
too.  $$$$$$$$$$$$
Mike MacLean
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