Wrist pin noise?!?
WFO Herb
Ulix Goettsch wrote:
> Fellow listers,
>
> I finally (after 2 years) got my new engine in the car and fired up for the
> first time. It ran nicely and I drove it 2 or 3 times when I started
> hearing a noise. It sounds almost like the engine is a diesel.
> The sound doesn't seem to change with load, only with engine rpm. It isn't
> very loud, no impending doom sort of noise, just a bad note to the engine
> sound. The knock is not a deep rumble, it's a lighter pitched knock, like a
> diesel.
>
> Listening around the engine I can tell that the sound comes from inside the
> engine, but opening the oil filler doesn't let it get louder. Using a steel
> rod as a stethoscope against the head or block doesn't help. Disconnecting
> the fan belt doesn't make the sound go away, nor does pushing in the clutch
> make any difference.
>
> I pulled the pan and looked around, tried to wiggle the crank and rods,
> retorqued the rod bolts, made sure the mains are tight. Found that one of
> the legs of the oil pickup was rubbing against a crank counter weight and
> thought I had found the problem, but alas, the sound is still there.
> There was nothing exciting floating in the oil pan.
>
> When I built the engine, I had the crank measured, it only needed polishing,
> it was already 10 under. The big ends were resized, new pistons fitted by
> the shop, block bored to match, mains line honed.
> New parts were: pistons, bearings, cam, timing sprockets and chain, lifters,
> valve springs, complete rocker shaft with rockers.
>
> I fitted all the bearings, plastigauged the mains and rod bearings, checked
> crank end float.
>
> In troubleshooting, what I haven't done is pull the rod or main caps. Since
> I haven't driven or run it much since it started sounding like this, I don't
> know if there would be visible bearing wear yet.
>
> I would be grateful for any suggestions of what to check, even crazy ideas.
> I'm in the process of moving and can only devote so much time to this at the
> moment. I want to drive this car so bad I can taste it.
>
> Thanks!
> Ulix __/__,__ ___/__|\__
> ..............................................(_o____o_)....<_O_____O_/...
> http://www.mirafiori.com/~ulix/ '67 Sprite '74 X1/9
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