What causes exhast leaks on the exhaust manifold/header?

[Neejay]

What causes exhaust leaks on headers? I have tightened the bolts + new gasket that came with the header, and I still get a high pitch rush of air sound when accelerating. This didn't start until I installed my header. I thought it was the EGR tube since it was cracked, but I took that off.

I even rebolted the header on + shifted the gasket, to no avail. Im using 2 egr/aiv oem plugs, but is there anything I can put around the threads that wont burn off?

EDIT: If the gasket is in the way at all of the ports, would that cause the exhaust leak sound?

[unicoladron]

it could be just exhaust turbulence..what kind of manifold do you have? if there are any non-smooth surfaces (ie welds that have sharp edges) it causes turbulence in your exhaust. that is why it's always good to grind down the welds or inside of the exhaust runners.

if you're using a decent quality exhaust gasket, and the mating surfaces of your block and the mani are clean and somewhat flat, there should be a tight seal. again it just sounds like turbulence.

are you noticing a power loss?

[Neejay]

Originally Posted by unicoladron

it could be just exhaust turbulence..what kind of manifold do you have? if there are any non-smooth surfaces (ie welds that have sharp edges) it causes turbulence in your exhaust. that is why it's always good to grind down the welds or inside of the exhaust runners.

if you're using a decent quality exhaust gasket, and the mating surfaces of your block and the mani are clean and somewhat flat, there should be a tight seal. again it just sounds like turbulence.

are you noticing a power loss?

Im using a ebay header, and yeah, the runners weren't smooth.

As for power loss...eh...I would say not. I didn't know turbulence would cause the air sound to be that audible.

[EAT Motorsports]

could just be crappy ebay headers with bad flanges also check all the welds.

[NemeGuero]

did you tighten the manifold in the right order per FSM spec?

but if its ebay header.. its probably from warping during the welding process. So the flange isn't flat.

[Neejay]

Originally Posted by NemeGuero

did you tighten the manifold in the right order per FSM spec?

but if its ebay header.. its probably from warping during the welding process. So the flange isn't flat.

No, lol. I thought maybe there wasn't a specific order since I couldn't find it. I'll look for it.

[S14DB]

ebay gaskets are crap. buy a real one and copper coat it.

[Neejay]

Originally Posted by S14DB

ebay gaskets are crap. buy a real one and copper coat it.

Done. I filled in all the grooves on the gaskets. I did the 3 coats (3 on header flange side, 2 on the side that will be on the head). Still getting the sound. I'll copper coat the the header collector-to-cat gasket tomorrow.

[S14DB]

Originally Posted by Neejay

Done. I filled in all the grooves on the gaskets. I did the 3 coats (3 on header flange side, 2 on the side that will be on the head). Still getting the sound. I'll copper coat the the header collector-to-cat gasket tomorrow.

Oh yeah those cat ones leak like crazy unless you coat them.

[articdragon192]

Try using OEM gaskets. When I did my header and exhaust swap, I used OEM metal gaskets all around and never got one exhaust leak. Ran it for over a year with it and no problems.

[Max_PSi]

My bet is on not torqueing the header down properly.

How long after your install did you notice a problem?

[Neejay]

Originally Posted by Max_PSi

My bet is on not torqueing the header down properly.

How long after your install did you notice a problem?

Immediately. lol

I bolted them down in order...now the tq amount...eh...

[mikethebiker]

oem aiv/egr plugs? i just used nickels, it only cost about 10 cents

[slideways2004]

Originally Posted by mikethebiker

oem aiv/egr plugs? i just used nickels, it only cost about 10 cents

lol

don't use ebay gaskets. i think mr. gasket makes a really good exhaust manifold gasket for the KA