Frank,
I would start by adjusting the valves and checking the compression.
HTH,
Peter Schauss
1963 BJ7
1980 MGB
> -----Original Message-----
> From: owner-healeys@autox.team.net [mailto:owner-healeys@autox.team.net]
> On Behalf Of fmags@cox.net
> Sent: Sunday, August 13, 2006 6:01 PM
> To: healeys@autox.team.net
> Subject: engine noise
>
> Hello all,
>
> I have an engine problem that I wonder if any of you have experienced or
> if
> anyone has any suggestions as to what it might be.
>
> I was sitting at a stoplight this morning and all of the sudden the engine
> starting making a loud tapping noise at idle. Had it towed home and
> diagnosed the following.
>
> I thought that maybe a valve spring had broken or a rocker arm had broken
> or
> somthing like that, but on pulling the valve cover off, everything seems
> ok.
> With the engine running with the valve cover off, all of the valves,
> pushrods and rocker arms are all moving nicely. Lots of oil getting
> splashed around as well.
>
> I pulled the spark plugs leads off one at a time and other then a slight
> RPM
> decrease, no change in the noise. With the cylinder not firing, I would
> have thought if it were a connecting rod bearing or wrist pin, the noise
> would have stopped or changed.
>
> The noise is definately louder with the valve cover off than with it on,
> and
> sounds like it is coming from the top of the engine. It is a loud tapping
> that changes directly with RPM. It is not a deep knock like a con rod
> bearing would be; It is a much lighter tapping.
>
> It almost sounds like a valve hitting the piston; maybe the timing chain
> jumped a few teeth? Other than the tapping, the engine runs smoothly and
> starts fine. I am trying not to run it any more than I have to to
> diagnose
> it as I don't want to cause more damage; whatever it is.
>
> Any ideas?
>
> Thanks,
> Frank
> '65 BJ8
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