[TR] TR4/Webers - that banging noise- #2

Lee&John Howard leejohn7 at gmail.com
Fri Aug 7 16:06:04 MDT 2009


I have now dropped the oil pan and removed the head and pulled the noisy
piston and cylinder. The sleeve pushed up when I pushed up the piston and
bent the gasket, so I will fit a new gasket.

I don't see anything. The rod cap was torqued properly with bearings in
place, the valves all look fine. Push rods look straight and true. No
scarring or marking of any kind in the cylinder. No marks on the piston
head. So at least  I did no apparent damage.

So what could the banging have been? To review, I thought the carbs were
noisy from the get-go, but convinced myself that it was the sound of Webers,
new to me. Then when fiddling around and trying to learn about these new
carbs, I removed the plug wire to #2 cylinder and the noise disappeared. So,
no combustion no noise. I'm quite sure the lash was set correctly. So
combustion is sending piston down more violently than non-combustion,
hitting something? I don't get it. Oil pan baffle is also unmarked.

I have reseated the sleeve and cylinder and the sleeve tops are proud ot the
block surface by the prescribed amount.

Any ideas? I hate to put it back together without "doing" anything, but
sometimes that works.

Many thanks, as always

John Howard

On Tue, Aug 4, 2009 at 2:30 PM, Lee&John Howard <leejohn7 at gmail.com> wrote:

> Well, I got compression readings today: #1 - 135. #2 - 130, #3 - 130, #4 -
> 135. So that indicates that all is well in the top end, right? And the next
> step is to drop the oil pan and see what might be amiss down there?
>
> Beginning to wish I hadn't sold the nice running and good looking 4.  Sigh.
>
> Again, thanks for your help
>
> John Howard


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