Barfly

Since I bought the truck I can hear an exhaust leak on the drivers side
inside the engine compartment.

It was my first inclination that the leak was coming from the doughnut where the pipe connects to the manifold, the sound takes me directly there. It's annoying as heck especially driving down the road as it's one of those leaks that sounds 'almost' like a lift ticking. But I know it's not as it has a real low muffled sound idling.

Before going to the track Friday night I changed out the spark plugs with a new set of Autolite's. Six of the old plugs looked almost identical, dry with a little white on them(what's that all about?). Two of the plugs, 5 and 7, which are located directly above the supposed leak were black with carbon. Carbon that was easily wiped off with my finger.

Now I'm wondering if the exhaust manifold is the leaking culprit rather than the doughnut seal. I've tried, with the engine cold to find the leak with my hand, see it, etc.....

Does anyone have a trick up their sleeve for for finding leaks of this type?

Thank you
Joe.

sweeperking

Just a thought here, I have never done this with a exhaust leak but I use this method to find air leaks on trucks. Get your self a spray bottle and fill it like 9 parts water one part dish soap. I guess you would have to be quick or the heat of the manifold will just evaporate the soapy water but with the engine cold start it and very quickly (<-- is that a word?) spray along where you suspect the leak. (just a thought) Or...assuming there is no crack in the manifold, why not just replace the gasket (to include the doiughnut)

ef8340

hey joe
i too have that ticking sound and i've found mine i went to change out my flange gaskets and upon further inspection i found that my pipes were cracked where the flanges started i tried the muffler goop patch crap on it but that isnt working the only other way is to take them loose and weld it up then grind it flush so the mounting bracket will mount up i've decided with mine im just going to cut them off and install headers i think that will fix the problem cause im guessing that getting on it from time to time the torque of the motor caused the cracks i think with headers i'll just end up replacing collector gaskets
Terry

MReeves

If you suspect its in the manifold take a feeler guage and run it along where the gasket lays between the manifold and the head. You will be able to feel if the gasket is loose or leaking.. We use this on header flanges all the time.. Works for us... Hope it will for you....

Barfly

Hey thanks guys. It's one of those things I keep putting off but needles me every time I start the truck.

I did get bubbles from around the doughnut, not like I thought I would but they were there. No room for headers, I would love to have them tho.

You know, my exhaust system is hung very well, maybe to well, and all the joints are welded. It's up there very solid, so the possibility of the flanges cracking like that is very possible.

I do have a feeler gauge, that's a good idea.

Thanks again
Joe.

Buffalojoe426

Wait till its dark, get some one to rev it up and look for the fire. You might have to look hard some times, but is an easy test.

Barfly

Oh for the love of Pete!
See that's why I love this forum, why can't I come up with
these things. Thanks!!

Joe.