"Eric" <say.no@spam.now> wrote in message news:4366D977.8E3CC5EE@spam.now...
> Peter H wrote:
>>
>> Hi Group: Hope someone here can help me with this question.
>>
>> I've got a minor leak in my exhaust manifold of my 2000 civic. I'm
>> wondering whether I'm doing my motor any harm by not having it repaired
>> right away. It doesn't seem to be affecting performance in any way, but
>> I've been told by a mechanic that it's there and I think I can hear it.
>>
>
> The potential for damage depends on where the leak is located. If the
> leak
> is at the junction of the manifold to the head, then the leak should be
> fixed promptly. Exhaust leaks at the manifold gasket have the potential
> to
> damage the flange sealing surface on the aluminum cylinder head. I
> witnessed this on a car owned by someone I know. He drove around with a
> very distinct sounding exhaust leak for several months. By the time he
> got
> around to replacing the manifold gasket the head had already been damaged
> and a new gasket made no improvement. If, however, the leak is from the
> exhaust manifold itself, then driving around with it for a little while
> might not be too offensive. It would be best to closely evaluate where
> exactly the leak is coming from and proceed appropriately.
>
> Eric

My favorite way of finding an exhaust leak is with a shop vac. Put the hose
on the outlet side, run the vac a minute to get any extra grit out of it,
and duct tape the hose to the exhaust pipe. It lets you work on a cool
engine and produces an amazingly strong jet from even a small leak. You can
easily feel it with your fingers.

Don't forget to remove the lash-up before driving! 8^P

Mike