header leak?

[deadlois]

Well, I hear either a somewhat highpitched rythmic hissing sound, or a possible tapping in my passenger side toward the front of the block. I hope it is an exhaust leak, but it might be a valve tap I guess. It seems to come from the side by the front header, at the same level as the header, and not above the valve covers. Any idea if this could be a header exhaust leak, or something more serious? The car seems to run the same, but I only had it for a lil over a month.

[kenmosher]

You can use a piece of garden hose to narrow down the leak ... it's not unusual for the headers to leak if they are cracked in the normal places (between #3 and #5 cylinders near the block).

See:

http://www.gnttype.org/techarea/engine/headercracks.html

[deadlois]

I'll look at the usual areas, can you elaborate on the garden hose?

[kenmosher]

Use a 1-2 ft long piece as a crude stethoscope ...

Hold one end to your ear and run the other end around the engine to localize the noise ... not terribly sophisticated, but works for me! :D

[deadlois]

well, I narrowed down the noise coming at the front passenger side part of the header, but I dont see any crack or feel any for that matter. I see an aftermarket(not original) bolt on the front part of the header, the bottom one to the head, could it be the header not seated right from a possible loose bolt or not tight enough? Would this make the noise I described earlier? thanks.

[kenmosher]

Yep, or it could be warped or misaligned.

[deadlois]

well, I guess I'll take the headers off that side and see if I can reseat it or fix the problem, I read from another post to use that copper rtv, so I'll start with that. Thanks for the help Ken.

[kenmosher]

Before you put it back on, it'd be worth it to use a machinist's rule to make sure the flange is flat ... if not, you can use a belt sander or an end mill and "kiss" it enough to square it back up.