Best way to check for exhaust leak?

[swettysblazer]

I've got an exhaust leak and its driving me up the wall. I checked the header bolts, tightened the collectors, and checked the muffler/ cat, and it all seems to be fine. It seems like its coming from the engine right under the drivers floor/ brake pedal. Whats the best way to check for a leak?

 

[K5dreamer]

ive always used my hand. start the truck cold so the exhaust isnt hot, and starting at the header flanges move your hand along the exhaust about a cm away, (1/2 inch for you old farts) and feel for the puff puff puff of an exhaust leak. move down the headers to the down pipes, and then along the exhaust. you should be able to feel it. if not, you can use a flame to find it. the puff puff puff should move the flame or blow it out.

 

[swettysblazer]

ive always used my hand. start the truck cold so the exhaust isnt hot, and starting at the header flanges move your hand along the exhaust about a cm away, (1/2 inch for you old farts) and feel for the puff puff puff of an exhaust leak. move down the headers to the down pipes, and then along the exhaust. you should be able to feel it. if not, you can use a flame to find it. the puff puff puff should move the flame or blow it out.

Hmmmm flame method sounds good. I tried the hand method and couldnt come up with anything. I was also thinking of Sea-Foaming the **** out of it and having the bitch smoke to all hell, but this is a better idea

 

[sweetk30]

2 people.

1 wet shop rag.

fire up and 1 person hold wet rag on tail pipe.

other person find leak.

 

[K5-Kelly]

Mine was doing the same thing (sounded like it was coming out of the floor boards) and this happened shortly after we put new high quality gaskets on it. Turned out that one pipe was protruding past the flange about 3/16" of an inch and was casing the header gasket to burn out early. I figured it out by looking closely at the head exhaust ports and I spotted carbon tracking. Once I pulled the header I had to grind it flush with the flange. High quality headers with jet coating on them, now they are probably gonna rust out.

 

[swettysblazer]

2 people.

1 wet shop rag.

fire up and 1 person hold wet rag on tail pipe.

other person find leak.

This basically doesn't allow the exhaust to escape, right?

 

[K5dreamer]

This basically doesn't allow the exhaust to escape, right?

you could do the same thing with a potato


kidding, kidding, please dont do that.

 

[obijuan]

i had a rust hole in my header tube so i put a screw in it. couldnt ever see it but my dad mentioned the lighter trick, worked terrible cause my fan was blowing.

 

[Jessie James]

I used to just hold a piece of paper up next to the exhaust until I saw it moving.

 

[NorCal_Chris]

take a funnel and a peice of rubber hose and attach it to the funnel. Stick funnel to ear and use hose to snoop around.

Best way to do it imo

 

[swettysblazer]

i had a rust hole in my header tube so i put a screw in it. couldnt ever see it but my dad mentioned the lighter trick, worked terrible cause my fan was blowing.

Yeah, i tried this before and the same thing happened.

 

[swettysblazer]

take a funnel and a peice of rubber hose and attach it to the funnel. Stick funnel to ear and use hose to snoop around.

Best way to do it imo

Hmmmm I'll try this one

 

[Hogback Fabrication]

2 people.

1 wet shop rag.

fire up and 1 person hold wet rag on tail pipe.

other person find leak.

This!

You won't hurt or kill the motor, raising the backpressure makes the exhaust leak much more noticeable.

 

[diesel4me]

Be careful using fuel line as a stethascope--the carbon black in it is an excellent conductor of the high voltage your HEI ignition makes--beleive me when I say you DONT want to get a shock like I did when I just put a 3 foot peice of 3/8" gas line in one ear and started probing for an engine noise source!..it really HURTS!..almost as bad as the shock I got from my old K5 when I leaned over the fender to adjust the carb and found a plug wire had a brnt spot--my hand touched it,and the spark grounded thru my body and jumped from the zipper on my trousers to the fender..
..my nuts hurt for days after that!....