Exhaust Leak

[83kid]

Hi,
So i have an 83 k10.
It has headers going down to a dual exhaust setup.
For a little more then a week now, i could hear a slight tick tick tick tick under harder acceleration from down and forward. I didnt think much of it
The other day, it got really bad. Under harder acceleration it is really loud, and very annoying.
The exhaust itself isnt exacty that loud, but mainly the tick part of it.
So, i believe it is an exhaust leak. Exhaust is pretty new, only a few years old, not all rusted. I tried tightening the header bolts on the drivers side, because that seems to be where its coming from, but they didnt really move, and that didnt fix it.

So, it sound like its coming down from where the header collectors are, so could it be the gasket there, a nut coming loose, or would it be the header gaskets? Or anything else?

Thanks!

 

[mtnmankev]

Do you hear it at idle?

If so, start engine and use a long piece of rubber hose/tubing, probably 3/8" or bigger.

Hold one end to your ear, and move the other end around the headers where they attach to the block, and where the collector bolts up.

You will hear it loud and clear when the other end of the hose is at the magic leaky spot.

 

[firebane]

Headers leaking? *GASP*

 

[83kid]

Not really. I dont know if it does when you rev it a bit, only got to a little above 2000 RPMs in park, didnt want to go any higher because of it being late at night and i didnt want to wake the neighbors.

A couple times at idle at a light ive heard it, but very very faintly

But ill try that, thanks!

 

[MadOgre]

Try using longer bolts with exhaust springs if it turns out to be the collector gaskets. Cinch them down as tight as possible.

 

[chengny]

Pour a little bit of MMO (Marvel Mystery Oil) down the carb throat with the engine running. Then watch for white smoke - where you see it - that will identify the leak.

 

[83kid]

Would it be pretty safe to say its gonna be the header gaskets?
I'm thinking should i just go ahead and place those and see if that works?

 

[350runner]

http://m.summitracing.com/search/product-line/percys-seal-4-good-header-gaskets

Sent from the dust in front of you!

 

[chengny]

Why do a shotgun repair when an accurate diagnosis takes about 5 minutes? If you don't have any MMO you can use ATF. Seafoam works real good too - but it's also real expensive.

 

[Skweegle89]

I would certainly try tightening those collectors before I went pulling the headers off.

 

[chengny]

Poke a few holes in a paper cup and jam it in your tailpipe. There will be enough flow to keep the engine running and the exhaust leak will start whistling like - it wants to be found. If the paper cup pops out, make another hole.

You know, I don't know what 83kid has for an exhaust system but he might need to restrict his exhaust gas flow to locate a leak.

When my truck (heavy duty emissions, no cats, 2 1/2" pipes front to back) is idling, the area around the manifolds/headers and down the line to the mufflers, runs at a negative pressure.

I still use the original A.I.R system. If I pull the air pump discharge hoses off the check valves, you can hear/feel the exhaust system sucking in a ton of air. The vacuum is strong enough that, if the hoses from the air pumps are still connected to the check valves - but the drive belts are off the pulleys, the air pumps will actually spin as the air is drawn through them.

Am I the only one who dumps MMO down the throat to find an exhaust leak. It works excellent. Try it sometime.

 

[350runner]

I do also... is an old trick and lubes the valves supposedly.

Sent from the dust in front of you!

 

[1low4x4]

If its headers...buy stage 8 locking fasteners and never touch it again

 

[83kid]

So , i replaced the gasket at the end of the collectors. No difference. Then, it had gotten bad enough that i went down and put my head next to the drivers side header bank, and could hear a loud tick. I went down below near the collectors, and could hear it, still kinda loud but not as loud as up top. It sounded very close because of the way it was echoing off all the metal there....
When i first heard it i went to tighten the bolts on the headers to make sure none was loose. I couldnt get at the back 2, because it was too hot and couldnt reach them without hitting anything, so i thought since no others moved it was good. Turns out those were quite loose, tightened em up and havent had a problem!

 

[Skweegle89]

So , i replaced the gasket at the end of the collectors. No difference. Then, it had gotten bad enough that i went down and put my head next to the drivers side header bank, and could hear a loud tick. I went down below near the collectors, and could hear it, still kinda loud but not as loud as up top. It sounded very close because of the way it was echoing off all the metal there....
When i first heard it i went to tighten the bolts on the headers to make sure none was loose. I couldnt get at the back 2, because it was too hot and couldnt reach them without hitting anything, so i thought since no others moved it was good. Turns out those were quite loose, tightened em up and havent had a problem!

You might check them again in a month or 2. They will probably need tightened again.