View Poll Results: striped exhaust manifold head bolts

1 drill and tap bigger bolt.

42.86%

2.helix coil and stay with 3/8 bolt

28.57%

3 put a nut on the back side of the the exhaust ear

28.57%

4 just put the bold in what threads are left

5 other (please tell)

Voters: 7. You may not vote on this poll

exhaust manifold threads

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Oct 1, 2008 | 09:45 AM

pintoches

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Joined: Jan 2005

Posts: 3,876

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From: Hollister MO

exhaust manifold threads

I have been working on my broken bolts on the exhaust manifold. 390

one of the holes i dilled off center messed up the threads how would you fix it

1 drill and tap bigger bolt.
2.helix coil and stay with 3/8 bolt
3 put a nut on the back side of the the exhaust ear
4 just put the bold in what threads are left
5 other

Oct 1, 2008 | 10:31 AM

tcbofade

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Joined: Apr 2006

Posts: 11,794

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From: Kansas City, KS

The situation sucks...the best answer I can see is to drill it out, and go bigger.

Oct 1, 2008 | 02:59 PM

Redmanbob

Logistics Pro

Joined: Oct 2005

Posts: 3,785

Likes: 4

From: Mddl A MexCans

Didnt you center punch it ? Awwhh man! Well whats done is done. The down side is that off center is off center so a larger bolt that isnt aligned is not going to line up with the manifold most likely. Id open it up and tap it. If it wont line up use the 3/8 bolt and a back nut and call it good.

Oct 1, 2008 | 10:14 PM

zstangkrewson

Senior User

Joined: Apr 2006

Posts: 329

Likes: 0

From: west plains, missouri

drill and tap a bigger bolt size, BUT id use a stud instead of a bolt, torque it i npolace good and use a nut on the outside of the manifold, use good grade stuff anf they wont rust in place.....good luck!

Oct 1, 2008 | 10:17 PM

zstangkrewson

Senior User

Joined: Apr 2006

Posts: 329

Likes: 0

From: west plains, missouri

sometimes you can get a smaller bit, dril la couple of holes (use tap oil it cuts easier) around the bolt through the threads, and it may come out on its own with vise grips, worth a try

Oct 2, 2008 | 07:16 AM

krewat

FTE Leadership Emeritus

Joined: Jul 2002

Posts: 42,561

Likes: 423

From: Long Island USA

If it were me, and I needed to get it done, I'd put a nut on the backside of the ear

If the hole is now off-center, it's going to be a bitch. BUT - if you can get it in straight, helicoil it.

Oct 5, 2008 | 10:08 PM

orich

Lead Driver

Joined: Aug 2003

Posts: 7,592

Likes: 10

From: **** hole San Jose ca.

Hmmm well, I'd bolt the exh manifold back on and see how the new off center hole lines up before anything. Then if ok you can do like above said to do. But if you try to retape the new hole the old broken bolt piece may come loose.Then what can you do? Yup drill it all the way out.. I've seen maybe 30 fe engine where people don't take the time to learn how to remove these type of frozen in bolts. Many times people replace them with new bolts using only grade#5 bolts that our to long that the threads stick out pass the ears then they rust on the bolt ends that stick out and really adds too the problems of removing them later.. my 2cents
orich