Need help with header

[choua1855]

Since Last Week I Keep Hearing A Clicking Sound From The Engine Bay When I Step On The Gas. I Asked Someone Who Is A Mechanic And At First He Said It Could Be The Exhaust Header Or A Bad Spark Connection, But After A Search Through The Engine He Is 100% Sure It's The Header Because There Is A Crack On The Header Where The Bolt Is Located. I Have Never Heard A Clicking Sound Coming Out Of A Crack Header Before. Could It Be The Exhaust Header?

On 73 240z If I Want To Take The Exhaust Header Off, Do I Have To Take The Intake Manifold And The Carbs Off First? I Have Never Done This Before, What Do I Need To Know In Advance For Nothing Having Too Many Problems At The End For Removing All Of These Parts? Thanks Again

[e_racer1999]

an exhaust leak will make a sort of "clicking" sound.

you don't HAVE to take off the intake manifold, but it's a heck of a lot easier to take it off.

besides a new header/exhaust manifold, you will need a gasket.

[=Enigma=]

Is that clicking sound you hear when there's an exhaust leak the sound of the intake valves slapping closed or something else?

[240ZGL]

First off, is it an exhaust manifold or a tube header ? You said it's leaking around the bolt hole, which one ? You have the bolts that mount to the head and the bolts down at the collector that the exhaust pipe mounts to. A manifold is going to be cast iron, a header is going to be steel tubes.

[Arne]

When the exhaust manifold/header is replaced, you will need to replace the gasket too. The intake manifold and exhaust manifold/header share the same manifold gasket. So the intake manifold will need to come off as well.

[justaZcarguy]

I agree about the intake coming off, but tell us, does the sound diminish once the engine is warmed up?

[choua1855]

first i thought the crack is on one of the exhaust header bolt but i guess i am wrong there are more than one crack now. please look at the picture. the cracks are on each tube of each header pipe. i dont know why there are small tubes on each header pipe.

the sound doesn't diminish after the engine is warming up, it actually gets worser after the engine warms up.

i found a header (MSA 3 into 2 Headers)from motorsport online store, does any one know do i need the one with smog or without smog and do these headers come with a gasket, if they don't, how or where can i find a good header gasket? thank you all again.

[Montezuma]

MSA sells a good header. Saul of MSA was at one of our Z club meeting and he told us the way he installs the header that they sell without it it leaking. I did not take notes on what he said so you are going to have to call him and ask. He will talk to you for sure. I recently installed one of the older MSA headers which were real prone to leaks, I used a medal gasket and cooper RTV, it started to leak a week later, so I re tighted the header bolts and it seems fine again. The newer MSA headers are supposed to be less prone to leaks, they improved the flange some. I went with the older MSA header because it was free.

[choua1855]

on my 73 240z E88, if i want to get the MSA 3 to 2 headers, do i need the one with smog or without smog? thanks again

[e_racer1999]

73 is smog exempt. you do not need the smog holes (it looks like yours were filled anyway)

there have been clearance issues with the 3-2 header and SU intake manifold in the past. not sure if it's fixed, but just something to watch out for

[2Forty]

I just installed a MSA 3 into 2 header on my 73. I changed intakes to a 72 w/roundtops. No clearance issues.

[3RD STRIKE]

Quick ? If the header is leaking loud enough that u can hear it, Wouldn,t it backfire when u let off of the throttle? :stupid: