Engine fault diagnosis here...
1725 engine with about 5000 miles on it after reboring and rebearing.
Suddenly started making a big end type knock on start up, that would
disappear as soon as oil pressure light went out. At same time, when
driving, if I pulled my foot off the accelerator, then floored it, a big
puff of blue smoke emits from the exhaust, and the engine pinks wildly for a
mo, then pulls fine with no smoke.
Oil must be getting into the combustion chamber somehow and diluting the
fuel, hence the pinking. I have just pulled the sump and big ends out, and
they look OK, so I don't think that is the source of the knock. However, the
big end clearances may be a bit on the large side to begin with (crank not
reground, only polished)
The prolem appeared suddenly, but has not worsened over 500 miles of hard
driving.
I did suspect the valve guides, but it doesn't explain why the problem
appeared suddenly.
Any ideas.
Greg
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