ARP head bolt havoc

[victorfb]

well after 2 weeks i finally found a set of ARP head bolts for my gen 6 502 with GM aluminum heads. i was so jazzed i was finally going to get the heads bolted on. so i thought. i follow the recomended presedures. correct torque sequence, and 4 step torque. first 30#s then 50#s, then 70#s then finally the recommended 85#s. well some went just fine, but then i get to a couple that just keep wanting to spin. i take one of the shorter ones out and notice its stretching like a mofo. (almost 1/4") and thats a short bolt, maybe 2".:eek: it did the same thing on one of the longer bolts, but i didnt let it stretch that far. what the hell is going on? :mad: :mad: :mad: i am sooooooo bummed out right now. i do have a set of ARP bolts for the iron heads and am using a couple of those to keep the preasure on the gasket even, but i have to return those.
has anyone had this problem with ARP bolts before? i thought they were the best. maybe its time to back to milidon bolts.

[Fiat48]

1st check that you used arp lube or motor oil as a thread lube. That changes how much the torque spec is. Should be a chart included with the bolts or on the box. You might go to arp website and see if torque spec is there also.
I have had problems with ARP. I stretched a new main stud once. I called them to tell them they had a problem. They kinda insinuated it was my fault and offered to replace the main stud. I declined and said I just wanted them to be aware of the problem. I took the main studs out and went back to bolts for the time being. Later did Milodon. Last year on a new motor we had 2 ARP rocker studs break on the first run. Maybe a bad batch, don't know.

[victorfb]

they say to either use ARP lube and torque to 65#s or motor oil and torque to 85#s. i used royal purple motor oil. i couldnt find the ARP lube. sure wish now i would have though. i dont think i would have gotten the stretch. but then again, you would think that the bolts should be able to handle it. i mean it felt like it was stretching at the 50# cycle. thanks for the input though. i know its allways a bummer. but in this case im kinda glad it has happened to someone in the past. just gives me a better idea of the quality ARP is putting out these days. maybe milidon will be the bolt for the future.
ive got the heads torqued now. but i had to use a couple bolts from an ARP set for the iron heads that were supposed to be going back to the supplier. but i didnt want to have a couple spots not torqued. guess im going to have to talk to ARP directly on this one.
the only bright side to all this is the fact that i didnt snap one off in the block. now that would have sent me over the edge.

[Infomaniac]

Does ARP not recommend 65 lbs for alum heads using ARP lube?
Look on the spec sheet toward the bottom just to be sure.

[BK]

So if your using thread sealant on the bolt you still suppose to lube them also? Can someone refer me to a diagram of the torque sequence for a bbc?

[HP350SC]

I just torqued my Gen VI iron heads at 68 lbs. on the short bolts and 75 on the long per fel-pro. (1047 gasket). Using the stock bolts, not studs. Studs are cool but not worth the expense in my application.

[Schiada76]

I've bought Milodon bolts that were stamped ARP when I took them out of the packaging. Does Milodon actually make their own fasteners?

[victorfb]

ARP somewhat contradicts themselves on the spec sheet.
1) "if cylinder head bolts protrude into blind hole, lubricate the threads with ARP MOLY ASSEMBLY LUBRICANT or 30 wt motor oil."
2) "ARP recommends useing the ARP MOLY LUBRICANT or at the very least, a good quality Moly Lubricant as opposed to motor oil. this is due to higher friction on the bolts as well as inconsistancies in the clamping force of the fasteners when motor oil (or low quality lubricant) is used".
3) "Torque values are based on 75% of the fasteners yeild strength. use the manufacturers torque sequence but do not use the engine manufacturers torque specs. Torque the bolts to 65 ft lbs for ARP MOLY ASSEMBLY LUBRICANT (or ARP THREAD SEALER) or torque to 85 ft lbs with 30wt motor oil".
4) "Due to the heat expansion rate of ALUMINUM, it is recommended that the torque should be 60 ft lbs with ARP MOLY LUBRICANT (or ARP THREAD SEALER)."
5) "NOTE: Do not use any other Moly Lubricant. Use only ARP moly lube or head gasket failer can result."
now i could not find the ARP MOLY LUBRICANT, and as the note at the very bottom says not to use any other moly lubricant, i was affraid to do so. thinking that the 60 ft lbs with some other moly would be too low of torque and allow the head gasket to fail. as you can see in # 2, they say to use the arp moly or at least a good quality moly, but then in #5 at the note they say to not use any other moly lubricant or head gasket failer can result. so what do you do if you do not have the ARP moly lube? thats why i used the best motor oil i had. (royal purple).
(BK) if you have the mark 4 block you need to use the sealant since the bolt holes go into the water jackets. and the ARP sealant IS the lube aswell. you do not use sealant AND lube. if you have a gen 5/6 with blind holes (not going into the water jackets) you use the lubricant only (no sealant).
try this link for the sequence. http://12.219.129.202/hi_po_chev.htm
you should find it there.

[Infomaniac]

I generally always have some ARP lube around.
I bet if you call them they will send you some.

[victorfb]

i did just call ARP and told them my problem. they said i did everything right. the oil was ok to use and the 85 lbs was correct. they said that the bolts my have been defective and will send me new ones to replace the extra ones i had to use in the set for the iron heads. they did question my torque wrench quite a bit, but its a good snap on 1/2" drive. i mean i havnt calibrated it every week but i dont use it that often like a shop would. besides, why would it be fine on some bolts and not others? i kept going back and making sure it clicked on the ones i allready did, then back to the one that keeps streching. i hear the click, go to the next. ok, so that bugged me a bit. its not like im useing a china made torque wrench. i now have a couple head bolts with 12 point on the motor and the rest 6 point, but atleast its all torqued down. im just hoping some of the other ones are not stretched and will fail later. i hate having to worry about that all the time while im out enjoying my day on the river. but hey, what can happen? maybe blow a head gasket, get water in the oil, ruin and spin a rod or main bearing, waste the cylinders and rings, throw a rod? no big deal. it can all be fixed, right? :( i guess im a little anal about this stuff), but i cant afford to be replacing motors and such. thats why i am putting all good quality parts to begin with. maybe i should just listen to what the drunk buddies say and "just run it":p ok, ok im kidding. gotta find some humor in this madness.

[victorfb]

oh, and i mentioned the contradiction on the spec sheet and they kind of shrugged and said "i know, i dont know why they wrote it like that" i guess i wasnt the first one to mention that.

[Boater Bill]

And then after you sort this mess out, pray that your headers fit without grinding. After installing ARP's on my heads, my Bassett TT header flange hit the top of the bolts. Had to grind the flanges to get them to clear. Wasn't a problem with the OEM bolts.

[BK]

Thank you for the info. That link isnt working for me.

[victorfb]

i had the same thought when i was useing one of the bolts from the other set. it was just a bit longer so i thought i would use 2 washers. after looking how close the bolt head was i went with just the one washer. i had enough depth in the blind hole. besides that keeps the correct torque reading. i have no problem grinding a bit of the header flange to make em fit. small price to pay to keep the head secured properly. but thanks for the tip. i wont be too surprised now if they do actually hit.

[Schiada76]

The washers also have a bevel on them, ask them on the phone if the bevel goes on the head or the bolt side.:D When I asked them it took about 15 minutes to get an answer.

[cyclone]

Originally posted by BK
So if your using thread sealant on the bolt you still suppose to lube them also? Can someone refer me to a diagram of the torque sequence for a bbc?
no thread sealant is necessary on a gen VI 502 block. the head bolts dont go into any water passages.

[victorfb]

the bevel is so that the washer will not interfere with the bolt head and shaft at its joining point. put the bevel toward the head of the bolt. that way the bolt head flange will have flat contact with the washer and the washer will have full contact with the head.
speaking of contact with the head, i noticed on my GM aluminum heads that the washers did not fit exactly flat and wanted to pull the head bolt to the side as you tighten them down. if yours are doing the same i would suggest you stop and remove the bolt and recut the surface area of the head. (iron heads should be no problem). i used a speacial bit made for a verticle mill, but did it by hand with a drill motor (taped off everything and stuck a small rag in the bolt hole). not the best way, but it was MUCH better than leaving it the way it was. after i did that the bolts stayed striaght in alignment and allowed for a good reading. most were just fine. it was the bottom short bolts that are below the exhaust ports. especially the end ones that do not have as much material casted and allows the aluminum to distort.

[Moneypitt]

Did I read corectly that your head bolts grew 1/4 inch?? That's incredible..........I would ask ARP to supply a complete replacement set, with the inspection sheet included. Do you really have any confidence in the ones that didn't fail YET? Motors aren't cheap and any weakness will soon be found...... I still can't believe the streech factor.........Moneypitt

[victorfb]

im with Moneypitt on this one too. if you read back a couple posts, thats exactly what i wrote. if a couple were bad, how many others are on the verge? i went ahead and assembled more of the motor, valve train, adjusted the valves and all, and even the intake, but i am going to try and get another set of bolts (and the inspection sheet. thanks for the tip moneypitt) from ARP and re-torque it all again. i just wont enjoy myself on the water if im constantly worrying about them head bolts.

[Snowboat]

Originally posted by BK
So if your using thread sealant on the bolt you still suppose to lube them also? Can someone refer me to a diagram of the torque sequence for a bbc?
Just throwing this out. The lube goes on the threads that the nut goes onto, not the other end. The lube must also be between the nut and the washer. I'd say you got a bad batch.

[Moneypitt]

Ken, you are right, except he's using ARP head bolts. I just seal the bottom of the studs and lube,(with the ARP stuff) the upper thread, washer, and nut. But with bolts, they say use the lube, but gen IV BBC head bolts are live to water so you gotta seal them??? ARP's instructions are somewhat confusing to say the least, and the torque specs aren't much better. That company is in my backyard, maybe I'll raise some issues with them.......Ray