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Discussion Starter #1
i just put on a set of aluminum heads(gt40y303)i bought the ford kit which has the felpro gaskets and arp headbolts.i believe i over torqued the head bolts. as i read the directions from ford i misread the last step, the directions read as follows:
torque all bolts in sequence to 35 ft lbs (fig 2)
torque all bolts in sequence to 55 lb ft (fig 2)
torque all bolts in sequence an additional 1/4 turn 85-90 degrees

somehow as i read that i final torqued the heads to 85 ft lbs, as i was torqueing to 35 lbs the lower futhest right head bolt felt like it was bottoming out, it was tight going in, so i backed it out and took some of the sealant of the threads and it went in fine until final torqueing when it felt like it slipped, i am not sure if it is stripped or creating hydrolic pressure,but it is holding 75 ft lbs of torque(i am afraid to go further to match the others)all holes were cleaned out with brake cleaner and tapped to clean the threads

my questions are first does this bolt go through the water jacket and even need sealant, it was not like the other lower bolts it was the same color as the upper (no sealant bolts)it is the stud looking one

second should i take this bolt out, take the sealant off and retorque

should i back off the other bolts and retorque to the right specs or will that effect my head gasket

and if it is stripped can i helicoil that with the head on (if it doesnt go into the coolant)

thanks in advance..........Vinny
 

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Vinny

From my recent experiences with head bolts / studs etc etc, I can tell you that all the lower threads do in fact go into the water jacket on a 5.0 roller block. I think I finally got mine to seal and not leak.

What I would do is to pull that bolt and check the threads on the bolt. If it looks in good shape then run a thread chaser or tap down the hole then re-install the bolt with sealer and torque to the ARP specs (not Ford). By the way the ARP bolts are NOT torque to yield bolts like the Ford bolts. Torque the lowers to 80 ftlbs and the uppers to 85 ftlbs. Do not turn the bolt the additional 90 degrees. You only do this on Ford specific torque to yeild bolts.

If you need to helicoil the hole you will have to remove the head. The outside diameter of the helicoil is too large to fit down the head bolt hole in the head.
 

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Mike Noyes, to hopefully increase my knowledgable a bit, what exactly are "torque to yeild" bolts? And what's the diff between ARP and the Ford bolts in how they torque? Tx.
 

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Discussion Starter #4
thanks Mike, i was told that the bolts are made by arp but i dont know for sure,thats why im not sure what to do with this bolt that has 75 lbs on it while the others have 85 lbs on them, i guess i will pull it and take a look at the threads first, then hopefully torque it down to match the rest, since i would assume these are the torque to yeild bolts since i bought them from ford(even if someone else made them).......Vinny......out to the garage
 

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Discussion Starter #5
well i pulled it out and the threads were fine, i forgot when i originally installed the bolt i put a washer on this one because the new bolt was a tad longer than the stock bolt, only on this one (the stud looking one)so i ditched the washer and groung the some what pointed end off the new bolt (which the old one did not have) cleaned the threads out , put new arp sealant on the threads and arp assembly lube under the bolt head and torqued it down to match the rest, i think what i felt was the slip of the washer

but my question now is since these probaly are the torque to yeild bolts and i have them at 85 lbs should i leave them since they may not torque right if i loosened them and did the 1/4 turn past 55 lbs, does anyone know what kind of torque would be on a bolt that is turned 1/4 turn past 55 lbs?, seems like it would be mor than what i have now, any comments, suggestions, thanks.......Vinny ( i really should get a wireless router and put my old laptop out in the garage)
 

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Discussion Starter #7
hopefully someone will know the head gasket question

i did find out that these ford torque to yeild head bolts can be used up to three times, it says it right in the ford catalog (gasket set m-6051-a50), so if the head gasket would be ok maybe i could replace each bolt one at a time with 50 lbs of torque then go to final specs and sequence and do the 1/4 turn thing

its still odd to me that torque to yeild bolts can be used again, maybe they are made by arp like i have heard

anyone??......thanks........Vinny
 

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Vinny

Be very careful with the head bolts. Torque to yield bolts are one time and throw them away. If they are ARP they will have ARP stamped on the head. As far as I know ARP does not make a torque to yield fastener. At least they do not list one in their catalogue. By the way you should download the ARP catalogue and read the tech info. It is very educational.

Torque to yield bolts stretch each time you correctly install them. You actually yield the bolt. This is so much easier and more consistent for production line use than trying to torque to a definite torque.
 

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Whats a helicoil; I've heard the term, but can't fathom what it is.
 

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A helicoil is commonly called a wire thread insert. It looks like a coil spring but the cross section is thread shaped on the inside and outside diameter so it is diamond shaped. The hole to be repaired is drilled and tapped oversize. The wire insert is then threaded into the tapped hole. The insert now has the original thread on the inside diameter of the 'spring'.

Look here if it sounds confusing.

http://www.helicoil.com/products/helicoil.html
 
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