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View Full Version : Exhaust Manifold Help please.....



89_Red_Xr7
10-16-2004, 09:48 PM
Ok, so today was swapping my transmission/clutch cause they are both fried. Everything came out in a jiffy exept for one problem. while taking off the exhaust, one of the studs on the drivers side collector snapped while i was taking the nut off. Ok, no problem, i have an extra manifold to throw on there.
After everything is out of the way, i pull the drivers side manifold. Only 5 bolts/studs came out with it....odd. So I get my extra manifold and an extra bolt from my parts car. As im putting the manifold on, all the bolts go in just fine. then comes the last bolt, the one that wasnt there. I start to put it on by hand and only get 5-6 turns in before it wont turn at all anymore....SH#!. Cross threaded....

Is there a way to fix the problem without pulling the heads? can i just take the proper tap(if i can find one in town) and rethread it? or will it be fine with just the 5 bolts? I've also put on the metal 94-95 mustang v6 exhaust gasket to help seal it up...

What should i do here? Im totally at a loss....

Andrew :(

Mike8675309
10-16-2004, 11:45 PM
Heli-coil.

You'll need to track down the proper bolt size (someone can help perhaps) and thread pitch. Then track down a proper heli-coil kit for it. This will require you to drill out the hole with a specific drill bit. Then install a threaded insert (heli-coil) with a tool. This threaded insert screws into the hole you drilled and then provides a new set of threads for the manifold bolt.

An interesting write up of these inserts used in such an application was found here:
http://cjsupra.kendra.com/Helicoil.html

89_Red_Xr7
10-17-2004, 12:37 AM
That works, I'll have to see if i can pick one up tomorrow..

Andrew



Heli-coil.

You'll need to track down the proper bolt size (someone can help perhaps) and thread pitch. Then track down a proper heli-coil kit for it. This will require you to drill out the hole with a specific drill bit. Then install a threaded insert (heli-coil) with a tool. This threaded insert screws into the hole you drilled and then provides a new set of threads for the manifold bolt.

An interesting write up of these inserts used in such an application was found here:
http://cjsupra.kendra.com/Helicoil.html

BobGPz
10-17-2004, 01:25 AM
Man that is going to be an akward place to try and drill. Even with the IC tubes out of the way.

XR7 Dave
10-17-2004, 09:08 AM
If it went in 5-6 turns by hand its not cross threaded. Before you go to all that work, you should just retap the threads. It's 8mm x 1.25.

I've also found that some manifolds seem to be warped and won't allow you to get the bolts started properly. In those cases I've drilled out the holes in the manifold for more clearance.

89_Red_Xr7
10-17-2004, 04:49 PM
Dave,
Just borrowed a tap & die set from a friend. ran it through and works like a charm now!

Thanks Everyone!!

Andrew