Engine Stripped head bolt in waterjacket

Blucifer99

I only understand every 3rd word
Jul 15, 2018
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Port Mcnicoll Ontario
Hey yall long time no talkie talk lmfao

Was doing a rebuild and when I was torquing the last head stud nut and boom the threads let go. Happens to be a stud that goes into the front lower head bolt that goes into the water jacket.. I was wondering if anyone's used a helicoil in that spot and it held up to being torqued to spec. I kno I could just step up head stud size to 1/2 but I would like to avoid that if possible. And I don't think the shops in my area sell timecerts or whatever they are called. So I was wondering if anyone's used a helicoil and it worked?? If not that sucks. I do have another good block but I'd rather not have to disassemble the one I have setup already.. so hopefully peoples had success using a helicoil in that location.

Thanks in advance. Been awhile since I've posted. Wish I could say I'm glad to be back on stangnet but ya kno haha. Foxbody life.. lol
 
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Blucifer99

I only understand every 3rd word
Jul 15, 2018
466
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Port Mcnicoll Ontario
Here's a good discussion on the topic. I like where one guy recommended even using a stud, at least in the position where the helicoil is. Heck, upgrade to stud in all holes for that matter.

I've read that thread.. didn't answer my question or atleast I didn't see any response to if someone's used a helicoil or if it held torque. Alot of opinions in that post but zero info for answers
 
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7991LXnSHO

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Timecerts are aluminum and hold head studs in 60 year old air cooled AL blocks.

With an iron 5.0 block, the stainless helicoil is the route I’d go. How many foot lbs are you applying? The first link has TQ specs. The second has about the different materials if you plan on taking it apart a lot, (probably not), and TQ specs. The water jacket is the issue I’d wonder about. Red thread locker on the outside of the coil, then the normal thread sealer on the bolt or stud threads sounds good.


 

Blucifer99

I only understand every 3rd word
Jul 15, 2018
466
35
38
38
Port Mcnicoll Ontario
Timecerts are aluminum and hold head studs in 60 year old air cooled AL blocks.

With an iron 5.0 block, the stainless helicoil is the route I’d go. How many foot lbs are you applying? The first link has TQ specs. The second has about the different materials if you plan on taking it apart a lot, (probably not), and TQ specs. The water jacket is the issue I’d wonder about. Red thread locker on the outside of the coil, then the normal thread sealer on the bolt or stud threads sounds good.


Well I torque my heads in between the range of 90-100 foot pounds because I run 10-14psi of boost thru this engine.. I just wanna kno if anyone's used a helicoil and it held up to that type of force. I don't plan on taking the stud out unless I do another teardown so it would be in place and not cycled in a out.. my main concern is initial torque strength and what a helicoil can handle.. last thing I want to do is drill out the block install the helicoil and during the stages of torquing the head down and then popping the helicoil out of the block.. I do have another block on stand by and I might just switch my parts to it.
 

Blucifer99

I only understand every 3rd word
Jul 15, 2018
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Port Mcnicoll Ontario
Well just noticed the blocks cracked near the hole that the threads ripped out of.. so chances are the block cracked opening the threads just enough for me to pop them out when applying the torque to the heads.. soo looks like I'm using my spare block after all..
 
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John Dirks Jr

there is enough sticking out to grab on to
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Well I torque my heads in between the range of 90-100 foot pounds because I run 10-14psi of boost thru this engine..

Sorry to hear you have to start over.

On your choice to torque 90-100 instead of the stock spec 65-72, is it proven to improve head gasket sealing on boosted engines? I'm asking because I'm considering re-torquing the head studs on my boosted 302 in the black hatchback
 

Bullitt347

I have been doing it wrong this whole time
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90-100 ft/lbs on a 7/16 stud is just asking for trouble.
The 1/2" head studs on a Dart Iron Eagle block are only torqued to 110 lb/ft
 

7991LXnSHO

wanna catch the space herp
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In case the helicoil comes up again, the 1/2” lubed fastener torque is 97 ft lbs. 7/16” info is hard to find, but the 7/16” repair kit for head bolts is easy to find. I doubt your higher torque figure would work reliably.
Too bad about the cracked block.
 

OldManRiver

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Feb 14, 2015
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ARP 7/16" stud install instructions state 3 steps to 80 lb/ft.
Just checking required torque frequently on boosted application may be the best option.
 
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90sickfox

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On boosted 5.0 blocks I like to see 1/2 ARP studs. I've drilled and tapped a few on my own. Now I get the machine shop to do it. The issue is bolt stretch. A 1/2 stud or bolt, of the same hardness, is harder to stretch than a 7/16th bolt or stud. It's easy to do and gives added clamp holding force when it comes to lifting the head. Upping the pounds of torque is counter productive. Bolts stretch a little during the torque process. Fasteners are more likely to snap or pull the threads out when over torqued.
 
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chrlsful

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"...the blocks cracked near the hole that the threads ripped out of...."
What I was thinkin due to WHERE you said it was. Forg welding w/magnaflux (pixy dust) after.

We hilicoiled the ford 6L TD that came to us for 1 each: head and exh studs. The blts pulled out were replaced w/studs as was the rest of head/exh B4 leaving the shop. No probems 15K mi, 9 mo later. Those were Not in thin casting.