Exhaust leak?

[scurley]

I just installed a set of Tri-Y headers on my 67 289 and had someone weld up the glass pack mufflers and dual exhaust. When we fired it up, he said there was a leak from the headers.

I am still in the process of re-tightening the bolts after every cycling of the engine's temperature. Every time, I can give each bolt about a quarter turn.

Is there an easy way to tell when/if the leak is gone?

Thanks!

 

[thehueypilot]

You could buy a mechanic's stethoscope to listen for a leak at the exact location. Did you tighten the bolts down by working your way from the middle to the outsides?

 

[scurley]

I did, and still use that pattern while re-torquing the bolts.

Should I keep doing this until the headers settle in and I can no longer torque the bolts or should I take them off and try a different gasket?

 

[thehueypilot]

Maybe a different gasket would help. Your not trying to use a copper gasket are you? The stock fiber/steel core should work just fine from FelPro or any good quality gaskets made in the USA.

 

[scurley]

It is not a copper gasket. It is the one that came with the headers. I don't know if it is a FelPro, but it is that style. I have a FelPro gasket, but is is the square kind for the stock manifold. The one that came with headers was rounded.

How much damage can I do driving around with a leak in the header area?

 

[thehueypilot]

It will just slowly burn the gasket away and could leak CO2 into the cab. Maybe your bolts are bottoming out before they touch the flange?

 

[68_stanger]

If your sure that the leak is up where the header bolts to the head then your doing the right thing. I've had more of a problem with headers leaking down at the collecter, A mechanic's stethoscope as mentioned would be ideal for finding a leak, or I've parked the car out in the cold weather and fired it up then just look for smoke coming from the pipes, seemed to work for me.

They also make locking header bolts that arn't suppose to loosen up once you get em tight. I have no experiece with them to say how well they actually work though.

 

[mustangdave]

The locking header bolts are "stage 8" and yes they do work. If the leak is bad enough you will actually see blue flame at the head if you run the car in the dark. I've never heard of anyone having this much trouble. Are you sure you got all of the old gasket material off before installation? Warped header flange?

 

[10secgoal]

I've never used the gasket that come with. They are always the paper ones and I tried and tried to get them to seal. Never could. Went to fel-pro, did a few heat cycles and they are good for over a year now.

 

[69 302/351c]

Just replaced mine after 6 years. I use the felpros...about $20-25 at your local auto parts store. I tried the locking bolts but they are a PITA with headers.

 

[scurley]

I have run it at night, and don't see anything. The only indication I have that there is a leak is the guy that welded the rest of the system up said so. I hear a ticking sound that gets worse while accelerating, but goes away while cruising.

I should hope the header flange is not warped.... the block that I have is new. Also, I spent a very long time scraping away the old gasket with a puddy knife.

So it sounds like the only damage I can do while trying this heat cycling/ torquing down is a burnt up gasket, which I would have to replace anyway if after the bolts stay put, it still makes the noise. Well that and a little CO in the cabin.. but that never hurt anyone right?

The locking header bolts are "stage 8" and yes they do work. If the leak is bad enough you will actually see blue flame at the head if you run the car in the dark. I've never heard of anyone having this much trouble. Are you sure you got all of the old gasket material off before installation? Warped header flange?

 

[10secgoal]

Well the exhuast won't work like it is supposed to. I have also heard rumor ( Don't know if it's true or not ( that you can burn a valve if the leak is bad enough/left alone.

 

[65fastback2+2]

i cant figure this part out, if you have a leak you will know it, it sounds like someone told you you have a leak and that is what you are going off of...

i dunno if this is a good idea or not, someone will say, but put a lil oil in the carb, the white smoke would come out the leak spot???