problem with start up after installing headers

[mark sexton]

After installing a MSA 6-1 header I am having problems getting the car started. When the engine is cranking, if I give the car some throttle a hear this strange clicking sound(my wife says it sounds like a woodpecker).It only occurs when the trottle is depressed. The engine is not starting quickly but i did get it to fire a couple of times and it ran very rough.I'm nervous about continuing to try and start it because of the noise. It does not make the noise if the choke is engaged without throotle input. Any ideas or help would be greatly appreciated. Car is stock 71 240

[LeonV]

Did you replace the intake/exhaust gasket? You may have created a vacuum leak.

[mark sexton]

yes the header came with a new gasket

[mark sexton]

I nalso installed a new exhaust from the header back. While the intake manifold a carbs were off the car I spent some time cleaning/polishing them.I did my best to not alter anything and just bolted them back on with the header

[beandip]

Hi Mark, Just try this, Pull the choke to full on. DO NOT TOUCH THE THROTTLE. The engine should fire right up. The clicking sound, could it be coming from under the dash on the passenger side. If so it is only the relays clicking when you turn the key.
Try this then let me know.
Gary

[mark sexton]

The noise is definately not coming from the passenger side,and does not occur when turning the key only if the trottle is also depressed.Thenoise is too loud to be a relay and sounds more mechanical. I could not get the engire to start with just the choke

[LeonV]

The noise is definately not coming from the passenger side,and does not occur when turning the key only if the trottle is also depressed.Thenoise is too loud to be a relay and sounds more mechanical. I could not get the engire to start with just the choke

Sounds like a vacuum and exhaust leak to me. Spray some ether or propane around the mating surfaces and other possibly exposed parts of the intake, to check for vac leaks.

Exhaust leaks will sound like clicks and should be easily detectable once the car is running.

[mark sexton]

Would an exhaust leak cause a noise if the engine is not running??

[LeonV]

If the engine starts to fire but doesn't catch, then yes. You need to be more descriptive of your problem, a video would help.

[Zed Head]

You've described the "after" but haven't said much about "before". How did it run before you installed the header? How long did it sit between the last time it ran and now? If it runs but not smoothly, it could be something simple like a misplaced plug wire. And the running rough problem might be totally separate from the odd noise.

[mark sexton]

the car ran great prior to the swap. It had a crack in the exhaust near the manifold. It was causing fumes and you could hear the leak but otherwise ran well. It sat for about 2 weeks while waiting for the headers.While sitting I cleaned up the engine block and repainted it. Also removed and replaced the starter motor to repaint and polish, but it seems to be working fine. I did have the plug wires off during this ,and was careful to keep the placement straight, and I did check the conections and they seem ok.

[beandip]

If it were a vacuum leak that kept the engine from starting it would have to be massive. Also if it were a vacuum leak, with the choke full on it should still start.
If all is as you claim here, I haven't a clue what the noise could be. Especially since the valve cover was not removed or unbolted, or the Dist removed.
I just re read your post. you did remove the plug wires. Go back and make positive that the connections are correct If you switch two wires .. this could be it.

[mark sexton]

Thanks for all ypur help. Last night I figured out the problem. Of course it had nothing to do with the headers, The coil was bad and jumping spark. Replaced the coil and starts right up. Still dont know what the noise was/is since it fires immediately. Sorry to be a pain and again appreciate the help

[Mike]

Thanks for getting back to everyone on this. I was going to suggest that it was electrical or fuel related because a header shouldn't prevent an engine from firing up...

[olzed]

Yes, it's good to get confirmation of a result.

Some don't bother.