ARP 7.3 Head stud Tourque

[jsnap]

Hi fellas I was reading the posts on the head stud torque specs for the 7.3 and you guys speak of a process thet requires tourqing and losening 5 times then a final tourq. I just got the studs from ARP along with the tourqe instructions for there 1/2 inch studs 200,000 psi and to be simple they say this. Screw studs in hand tight only lube the threads of course . Then follow manuf sequence but not spec,s and the spec to follow is 90lbs if you use there moly lube or any other moly lube or 130lbs if you lube threads and washers with 30 weight and thats the shooting match. So am i missing somthing here I think they should know what they want done to the product they enginered and built so what do you think.

 

[hesutton]

This is from ARP's website:

Friction

Friction is an extremely challenging problem because it is so variable and difficult to control. The best way to avoid the pitfalls of friction is by using the stretch method. This way preload is controlled and independent of friction. Each time the bolt is torqued and loosened, the friction factor gets smaller. Eventually the friction levels out and becomes constant for all following repetitions. Therefore, when installing a new bolt where the stretch method cannot be used, the bolt should be tightened and loosened several times before final torque. The number of cycles depends on the lubricant. For ARP recommended lubes, five loosening and tightening cycles is sufficient.

Hope that helps.

Heath

 

[jsnap]

I knew this and second guest myself reading these posts and made a call to ARP and ARP confirmed that the 5 time tourqe and release method is only for Rod bolts PERIOD ROD BOLTS and if you tourqed and released head studs 5 times you would actually weaken the chambers seal cause you crush the hell out of a perma torq head gaskets. This is a Classic example of a person giving advise to people when that person should be taking advice. And before you know it you have a disaster in this case in the form of head gaskets on borowed time. Good Luck to All that did it.

 

[jsnap]

Damn fellas i thought this thread would get alot of hits dont anyone have a comment or opinion maybe an explanation about this head stud torqueing faux pas.

 

[icanfixall]

Ok I'll bite... I believe I'm the person that started all this torqueing 5 times. Why you might ask... Because it works. This is from my personal experiance. I drove up to ARP... I had issues with some studs of theirs... They gaulded nut to stud... Not fun either. I used there molly lube too. For around 2 hours I talked with the two most senior engineers... They both told me the 5 times torquing and release procedure and it works. I did one stud this way. The sixth time it had turned the nut almost 3/4 turn more than where it started. The friction was reduced that much... No it didn't stretch either. Now to answer the ruining of a head gasket.. This is true but... You are not going to reuse a head gasket thats been tightened and loosened 5 times anyway... Or are you... I don't think so. Just reuse an old head gasket if they come off in good shape... Or buy one cheap head gasket and use the torque process stated. Then get rid of it and install a quailty head gasket. If you had a tool jib that setup like a head had block just run in the stud and torque it down and loosen it 5 times. Yes its lots of work but once its done you good forever with these studs.. Can you say that with 6.9 head bolts or 7.3... I don't think so.. Whomever at ARP told you the 5 times torque was for rod bolt only was out of line saying that. Hell... You can't even get the puick on the order desk to find the studs for the 7.3 motors. Its not in there inventory.. Sometimes its nice to know more than the person trying to sell you something... Some have installed the studs in the 7.3 without ever torquing 5 time and loosening. They have tens of thousands of trouble free miles and will continue to. I do what I do for the insurance I want. You do what you want for what you need. This advice is given free. I did all the testing so you don't have to. Also I will never know everything... But I continue to learn here...

 

[jsnap]

I dont know they got the head studs for me in about 2 minutes and you know what, it was a very nice woman by the name of Kammy Echiribel she impressed me knew a whole lot about fasteners anyone need anything call her. And whether you want to beleive it of not that extra bit of turn on your nut was because you stretched the head studs.

 

[comotionman]

hey icanfixall, i remember reading about the stud galling situation you had. can you please remind me of the exact procedure you were using when this occured and then please tell me what your new procedure is? as i have some ideas and input i would like to share, and would be interested in your(and everyones) thoughts.

 

[icanfixall]

JSNAP... What basis do you lean on for this stud stretching thought..... I can learn something if you can give information about this stretch... I don't feel they stretch. My facts tell me differantly than yours. Please share your thoughts here...
Comotionman... Even the ARP engineers couldn't tell be excatly why the 6 studs gaulded. They felt the black oxide coating may have chipped off and fouled the threads. They were really locked up. They would thread up or down on the stud. I continued using the same method they suggested. That was their molly lube and 100 lbs of torque. I was lucky because I had a new Felpro head gasket that I thought I had installed upside down so I removed the head. Only yo find it was installed correctly. So I had a new used gasket. Also I had another block and spare head. So I used them for the 5 time tightening and loosening method. Just the thinking about the differance in using 30 wt oil and 130 lbs of torque as compared to 90 lbs and the ARP molly lube tells me plenty. Its their studs and their lube... They know what they are doing. PS... They supply lots of studs for the top fuel market too... Same procedures too. I think they run a 9/16 or 5/8 stud..... Don't have the psi rating though...

 

[jsnap]

Icantfixall:Heres the deal if arp knows what they are doing you need to do 1 thing LISTEN TO WHAT THEY SAY once again I am looking at the directions, I cant copy and paste them for somereason but if anyone wants them ,send me a private with your email and ill forward the email arp sent me to you...... But again in a nut shell HERE IT IS...... Screw studs in HAND TIGHT ONLY lube the threads of course . Then follow manuf sequence but not spec,s and the spec to follow is 90lbs if you use there moly lube or any other moly lube or 130lbs if you lube threads and washers with 30 weight and thats it period... You dont see anything about tourque and loosen them 5 times untill you CAUSE THE BLACK OXIDE TO CHIP OF, AND CAUSE THE THREADS TO GALL LIKE YOU DID. In your post your even advising people to use an allen wrench and tighten the stud in the block. And once again the designers and enginers that made i dont know a gazillion fasteners say HAND TIGHT ONLY in bold letters but you know better, and want them tightened in..... Im sure when you went to ARP and sat down with their engineers and asked them what caused this, and they said did you follow the supplied instructions you said of course i did. Cause if you would have told them that you tourqed them up and down 5 times in 10 minutes they would have told you that you stretched the bolt and caused the finished to fail, and @ that point would have thrown you and your galled studs out. Nothing personel but like I said some people should be taking advice when there giving it. And just maybe there are some members here that are trying to do there own work, and do it rite thats why they ask, and you give them this advice and never once mention in your post DO NOT USE THE HEAD GASKET you just reused 5 times, with these torque directions i just gave you. Cause you assume everyone is as sharp as you and know not to use the same gasket that they just used to stretch there 300.00 or depending where you buy them around here 390.00 head studs with , and they do leave that gasket in place what then its a failure waiting to happen.