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Broken exhaust manifold stud!
https://www.slantsix.org/forum/viewtopic.php?t=12392		 Page 1 of 1
Author:  Oldsarge [ Sun Mar 27, 2005 8:57 pm ]
Post subject:  Broken exhaust manifold stud!
I decided to keep the '64 and get it road worthy, so I spent the weekend replacing tires, shocks front & rear, all fluids & filters, and she fired right up, except for the huge gaping cracks in the exhaust manifold! Luckily, I have a spare in the garage....

When I started to pull the manifold nuts off, I discovered there wasn't one on the rear top. DANG! Pulled everything, and sure enough, it was snapped off. So I pull out the drills and EZ-Outs ready to do battle, and to top it all off, the PO from hell tried to drill it out & snapped off the bit inside the stud. Double DANG!

Tried as hard as I could to work around it, but no luck..... Any ideas on how to get that thing out without pulling the head? I thought I'd pick up a carbide bit & try to drill it out a bit bigger & tap bigger threads, but was wondering if there's any tricks I might try first.

Other than that, it was running pretty good even with the cracked manifold & the carb was so loose I could pull the mounting nuts off by hand! I'm looking forward to putting it all back together tomorrow & firing it up. I have a Super Six sitting on the shelf, but I need a kick down cable & carb rebuild before I can think about swapping it out...

Thanks for the help!

Mike
Author:  SlantSixDan [ Sun Mar 27, 2005 8:59 pm ]
Post subject: 
Hooboy. Been there and done that, with the top/rear stud, on my former '65's original engine. I don't have many wise suggestions for you here. My solution was a mess and involved a jigsaw, a hammer drill, an oversize stud, plenty of JB-Weld and a Plexiglas heater strip.

I recommend you start with a large bottle of liquor.
Author:  dart63 [ Sun Mar 27, 2005 9:08 pm ]
Post subject: 
I would use a good carbide bit, a little bigger than the stud, drill directly into the stud deep enough to insert a helicoil and oversize stud. I was able to do this once using a carburetor stud in place of the manifold stud which worked perfectly giving me oversize threads to tap into the helicoil, and the proper threads for the exhaust manifold nut on the manifold side.

It's not a pretty situation, good luck. Why is it always the top rear anyway?? I have the original head from my 63 Dart ready to go to the machine shop for rebuild...sure enough, with broken top rear stud........that's the best sollution make it a machinists problem :lol: :lol:
Author:  SlantSixDan [ Sun Mar 27, 2005 9:11 pm ]
Post subject: 
The top rear stud is the most prone to break 'cause the manifold warpage is greatest at the ends, and the top rear is the hottest area of the head.

Make that carbide bit a left-twist (reverse-twist) bit and your odds get even a little better...
Author:  Oldsarge [ Sun Mar 27, 2005 9:52 pm ]
Post subject: 
I knew about left-twist bits, but never even thought about it until you mentioned it! I'll post results tomorrow after I wrassle that thing out of there!

Thanks!

Quote:
The top rear stud is the most prone to break 'cause the manifold warpage is greatest at the ends, and the top rear is the hottest area of the head.

Make that carbide bit a left-twist (reverse-twist) bit and your odds get even a little better...
Author:  Pierre [ Sun Mar 27, 2005 10:56 pm ]
Post subject: 
Use a center punch as well to mark the broken stud, that way you won't be drilling off center

Left twist bits are neat, I've had them "unscrew" a broken screw in one piece when trying to drill one out.
Author:  johnnysix [ Sun Mar 27, 2005 11:58 pm ]
Post subject:  loose carb
Remind everyone,when you buy a slant car ,tighten the carb bolts!! They rattle loose from improper tune. Gotta love a car that runs with the carb just sitting there!!!
Author:  dart63 [ Mon Mar 28, 2005 5:20 am ]
Post subject: 
I'm surprised you had any vacuum at that point. Must have been some good gasket sealant :lol: :lol:
Author:  Oldsarge [ Mon Mar 28, 2005 7:51 am ]
Post subject:  The carb is supposed to be tight? :-)
Actually, no sealant at all! I went to take the air cleaner off & the whole assembly moved! On my way out the door to pick up all the gaskets & parts I need to get it back together. May as well do the valve cover while I'm at it, and since that's coming off, I may as well adjust the valves.... I'm hoping it's pretty smooth after I get it back together. I have some upgrades planned, but that'll have to wait until later in the summer.

Thanks for the help!
Quote:
I'm surprised you had any vacuum at that point. Must have been some good gasket sealant :lol: :lol:
Author:  MileHighDart [ Mon Mar 28, 2005 8:46 am ]
Post subject: 
I just delt with the same thing on my 68 dart.
The upper rear stud was broken off, flush with the head. But nobody had broken a drill bit off in it yet.
I drilled it out with a 5/16" bit and tapped it with a 3/8" coarse tap, then just used a 3/8" stud. But i've heard the helicoil might be the better way to go.
remember when you put your new stud in, to use some good thread sealer since that bolt goes into the water jacket. I had a leak when I put mine back together,, had to take the stud out and put a good coat of sealer on it.

Good luck !
Author:  Oldsarge [ Mon Mar 28, 2005 7:20 pm ]
Post subject:  Done!
Finally got the broken stud fixed today! Used a carbide burr, and hogged the whole thing out & installed a hellicoil.... was easier than I thought!

New gaskets, ran a die over all the studs, cleaned & painted the intake, and she fired right up! Ran it for about an hour, and she purrs like a kitten... couldn't be happier!

Onward & upward! Now I have to locate the leak that's flooding the driver floor pan, and I don't think it's a wiper pivot seal :(

Oh well, at least she's running good!

Thanks again for all the help!
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