Author Topic: Stripped threads  (Read 2002 times)

Offline 70mopar

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Stripped threads
« on: April 20, 2012 - 08:35:54 AM »
I have a 1977 440 engine that is in a 70 Challenger. The valve cover bolt hole in the cylinder head, right behind the alternator, is stripped out. How do I repair this without removing the head?

Thanks




Offline ChallengerHK

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Re: Stripped threads
« Reply #1 on: April 20, 2012 - 08:58:39 AM »
You can try to use a helicoil.


"She'll make point five past light speed. She may not look like much, but she's got it where it counts, and I've made a lot of special modifications myself."

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Offline Oldschool

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Re: Stripped threads
« Reply #2 on: April 20, 2012 - 09:05:47 AM »
X2  ^^^
Ken  --  In Georgia

MOPAR-------"Built To Run------Here To Stay"

Offline 70mopar

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Re: Stripped threads
« Reply #3 on: April 20, 2012 - 09:16:05 AM »
I haven't removed the valve cover yet so I didn't know if there was enough material between the bolt hole and the edge or the head to drill a larger hole for the helicoil. Also does anybody know how deep these holes are. Does anyone have any experience with Time-Sert insertes?

Thanks all

Offline GranCuda1970

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Re: Stripped threads
« Reply #4 on: April 20, 2012 - 09:33:58 AM »
Stripped smooth or is there enough thread to chase it with a tap? I have learned things that look Fubar sometimes can be fixed.

Offline 70mopar

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Re: Stripped threads
« Reply #5 on: April 20, 2012 - 09:45:34 AM »
Dont know if it is stripped smooth, havent removed the valve cover to see down the hole better, just know its stripped.

Offline 72cudamaan

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Re: Stripped threads
« Reply #6 on: April 20, 2012 - 12:15:22 PM »
Time serts are a solid helicoil. They also need a larger thread to thread in to, so don't use that.
Can you drill the original hole deeper and tap it? Then just use a longer bolt.
If I cant fix it, it's broke
 
Andy  (phukker whither)

Offline Bullitt-

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Re: Stripped threads
« Reply #7 on: April 20, 2012 - 12:20:09 PM »
Or maybe just a smidgin longer bolt will solve the issue 
Wade  73 Rallye 340..'77 Millennium Falcon...13 R/T Classic   Huntsville, AL
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Offline 70mopar

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Re: Stripped threads
« Reply #8 on: April 20, 2012 - 12:38:27 PM »
I tried a longer bolt but it seemed like it bottomed out right away, as if someone else already did this and now there are no more threads left.

Offline ChallengerHK

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Re: Stripped threads
« Reply #9 on: April 20, 2012 - 12:58:57 PM »
Which is entirely possible.


"She'll make point five past light speed. She may not look like much, but she's got it where it counts, and I've made a lot of special modifications myself."

- Han Solo, Star Wars

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Offline the_engineers

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Re: Stripped threads
« Reply #10 on: April 20, 2012 - 01:04:40 PM »
Helicoil is your best option.
Brooks

1971 'Cuda 360
2004 Infiniti G35 6-spd Coupe
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1972 Dodge Dart Swinger...keeping the Slant.  Rocking the turbos.

Offline 4 speed fish

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Re: Stripped threads
« Reply #11 on: April 20, 2012 - 01:47:47 PM »
I would drill a 1/4 in down and then tap it,use a 1/4 longer bolt,you only need the bolt to grab a few threads.I would use some silicone on the bolt so it will not back out.

Offline ChallengerHK

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Re: Stripped threads
« Reply #12 on: April 20, 2012 - 01:52:19 PM »
Any bolt has about 60% of its tension on the first thread and about 30% on the second thread, and the rest is distributed throughout the length of the remaining threads. So, in other words, if you've engaged two threads, you've got 90% of that bolts potential working for you.


"She'll make point five past light speed. She may not look like much, but she's got it where it counts, and I've made a lot of special modifications myself."

- Han Solo, Star Wars

Advice Thread - Taking Pictures Of Cars

Offline PlumCraZRT

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Re: Stripped threads
« Reply #13 on: April 20, 2012 - 02:11:35 PM »
I would put a 1.5D helicoil in that bad boy then go pound a beer.  :ylsuper:
mmmmm.... Mopar.... *drool*

Offline 70mopar

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Re: Stripped threads
« Reply #14 on: April 20, 2012 - 07:15:34 PM »
Thanks for all the advice guys. Looks like I got some decisions to make.