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Header gasket/leak?

1STMP

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I just did a compression check on my 440.
The cam has just been broke in and I have
timing and carb set to where it's running
smoothly. All 8 @ 150 psi.
Due to this engine being so loud, it's difficult
to diagnose a constant tick that can barely
be heard above the noise. My guess is a leaking
header gasket.
With the valves/pushrods/rockers/lifters
seeming to be functioning properly, should I
be checking for anything else that may be
the cause?
Thanks in advance for any suggestions.
20190524_173953.jpg
 
Mine almost always leak out the center too, typically out the bottom.
 
Chances are if you have a gasket leak the flange isn’t flat. The problem will reoccur. I flat file every header. Occasionally it may take a bit of weld to build it up 1st.
Doug
 
If the leak is at the header, along with dvw advise. Consider REMFLEX header gaskets.
That's all I use anymore.
 
Chances are if you have a gasket leak the flange isn’t flat. The problem will reoccur. I flat file every header. Occasionally it may take a bit of weld to build it up 1st.
Doug
Thanks, Doug.
The headers are a custom build. The vendor that
built them for me is local. I will consult with him
if it does turn out to be a header leak. I do know
I'm probably not using the type of gasket he
would recommend, as the engine was assembled
at a different location.
20190108_143834.jpg
 
When you first start it you can wave your hand around the ports and feel an air leak.
You can't do it very long before the metal will burn you.
So it can take a couple tries to check them all.
 
Chances are if you have a gasket leak the flange isn’t flat. The problem will reoccur. I flat file every header. Occasionally it may take a bit of weld to build it up 1st.
Doug
100% this. I'll show a customer or a buddy how to prepare a header for installation(yes even brand new ones), and it's head explosion time.

"Do you want to seal up your headers in one easy installation, or be one of those internet whiners that say all headers leak. Up to you."


Edit* no offense to those that don't care for headers*
 
Last edited:
100% this. I'll show a customer or a buddy how to prepare a header for installation(yes even brand new ones), and it's head explosion time.

"Do you want to seal up your headers in one easy installation, or be one of those internet whiners that say all headers leak. Up to you."


Edit* no offense to those that don't care for headers*
The header manufacturer I use has a very
good reputation. He's certainly not some
fly by night quick buck operation, and has
good standing with the racing/hot rod
crowd. I've a set of his headers on a 360
CID Jeep CJ7 (that haven't been filed or
modified) for 20 years. Not a single leak,
and have been trouble free. I trust he instilled
the same quality into the set installed on my
440. The only variable that I question would
be the gaskets that he would recommend,
as the headers he built were installed with
a set of copper gaskets. (my choice). The flanges
on this set of headers are straight, flat, and true.
I'm pulling my valve covers off today, to try
and diagnose the engine tick. Thanks for your
input.
 
I discovered.. after many years wondering why... that the raised bead of the header flat flange (SB Hooker Competition series) wasn't sealing properly to the gasket... there simply wasn't enough flange area of the bead to seal properly to the gasket. So... I used Extreme Heat JB WELD and puttied it up (all the port areas per header flange), allowed to dry a day... then flat filed the JB WELD... so.. there was now a wider sealing area of the flange to the gasket. Perfect!!!! No more exhaust leakage!!!
 
If the leak is at the header, along with dvw advise. Consider REMFLEX header gaskets.
That's all I use anymore.

Ditto on the Remflex! I had one set go more than 10 years without a leak and never once tightened them after the initial install. They probably would have gone longer but I swapped the heads out.
 
pull one plug wire at a time....... when the tick goes away, you found it
 
Mabey I have just been lucky but plain old felpro exhaust manifold gaskets seals my headers just fine,
They are one use only though. Pull a header you need another gasket .
 
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