Retorque of ARPs with GM headgaskets?

scojack_2001

Livin' Like A Refugee
Just put the heads back on my motor. Used stock GM gaskets again and fresh ARPs rated to 200,000psi tensile strength. Torqued to 85 ft. pounds with a brand new torque wrench. They have sat for just about 24 hours as of right now. Will break them loose one at a time tonight and do a final torque.

Do I have to retorque them after a few hundred miles? There seems to be some debate on this subject. Not looking forward to doing this job again any time soon.

Thanks.

Scott
 

Phoneguy

Cometic HG stress tester
I would not break them loose, could disturb the thread sealant on the bolts causing a leak. You did use sealant right ?? I wouldnt think a stock style gasket would require a re torque, but if you are dead set on doing it I would get the engine up to operating temp a couple of times and then re torque without breaking them loose

Bryan
 

scojack_2001

Livin' Like A Refugee
I would not break them loose, could disturb the thread sealant on the bolts causing a leak. You did use sealant right ?? I wouldnt think a stock style gasket would require a re torque, but if you are dead set on doing it I would get the engine up to operating temp a couple of times and then re torque without breaking them loose

Bryan

Ok. I guess I'll just hit them again with the 85 ft. pounds and let it ride. Thanks Bryan.
 

TurboDave

RIP DAVE
Staff member
TurboBuick.Com Supporter!
Phoneguy is correct, if you're talking head BOLTS, then you do NOT want to retorque them, nor do you need to.
 

TurboDave

RIP DAVE
Staff member
TurboBuick.Com Supporter!
I can't get the link to pull up, but as long as you put the sealer on the threads only, and the lubricant on the head/washer only, you're good to go.
 

we4Mateo

Double you eee what?
When we did my engine with ARP bolts and stock HG's, we retorqued four times before putting it back in the car and they moved up until the last retorque. We did it in the morning, once in the afternoon, once in the evening, and then one final the next AM before we put it back in the car. They've sealed great since!

It may not be required but the stock HGs are thick and take a bit to settle in. I wasn't comfortable until the bolts showed good torque without movement or at least minimal movement after being left to settle. And this method is at least easier than heat cycling and doing it in the car. I also agree to never back the bolts out.
 

scojack_2001

Livin' Like A Refugee
I can't get the link to pull up, but as long as you put the sealer on the threads only, and the lubricant on the head/washer only, you're good to go.

Thread sealer on the bottom of the bolts, and lubricant under the head of the bolt and on both sides of the washer.
 

scojack_2001

Livin' Like A Refugee
When we did my engine with ARP bolts and stock HG's, we retorqued four times before putting it back in the car and they moved up until the last retorque. We did it in the morning, once in the afternoon, once in the evening, and then one final the next AM before we put it back in the car. They've sealed great since!

It may not be required but the stock HGs are thick and take a bit to settle in. I wasn't comfortable until the bolts showed good torque without movement or at least minimal movement after being left to settle. And this method is at least easier than heat cycling and doing it in the car. I also agree to never back the bolts out.

Thanks. Gonna hit it with the 85 one more time then it should be good to go. Still considering checking them after a few hundred miles and some boost (like 10psi or so).

Was instructed by a local TR owner/mechanic who i trust to break each bolt loose 1/2 turn and retorque. Not sure if I want to to that or not. We'll see.
 

TurboDave

RIP DAVE
Staff member
TurboBuick.Com Supporter!
Retorqueing studs is always a good idea, Bolts? no. You can check the torque, but not a good idea to back them out any for re torqueing.
 

TexasT

Texas, Where are you from
I cant see any advantage to "breaking them loose". Re-torque yes, I torqued it down, let it sit over night, re-torqued, then ran it and re-torqued one more time. Victor Reinz gasket(I only did one side.)

What is his logic for "breaking them loose"?
 

Slow91z

Turbobuick.com Helper
Staff member
With good thread sealer you can retorque it's not like rtv that will break lose and then leak.

Most of the time if you back the fastener an 1/8th to 1/4 turn then torque you will get more press out of them because you aren't fighting the break away torque it takes to get it turning...in other words even if it just clicks when you try to torque the fastener, if you back it off slightly you may still get more turn out of it.

Do 1 fastener at a time so the press stays on the gasket.
 

scojack_2001

Livin' Like A Refugee
I cant see any advantage to "breaking them loose". Re-torque yes, I torqued it down, let it sit over night, re-torqued, then ran it and re-torqued one more time. Victor Reinz gasket(I only did one side.)

What is his logic for "breaking them loose"?

I guess taking the tension off of them. Not sure what I want to to. Gonna go with Collin here and back them off a bit then take them back to 85. Hopefully that will be good. The engine has been sitting for just about 40 hours now.
 

earlbrown

runs with scissors
If you want to satisfy your curiosity mark the position of the bolt head before you crack them loose and retorque them.

I'd probably drop a GM seal tab in the radiator just in case you disturb the sealant.
 

TexasT

Texas, Where are you from
Good Plan.

I guess I can see the "extra" the bolt needs to over come the "break away" but relaxing the seal is too much for me.
product_thumb2.php

x2 on the seal tabs. I used this on the threads.
 

scojack_2001

Livin' Like A Refugee
I think Im just gonna hit them one more time at max torque and ship it. I need to get it back together again. Will drop some seal tabs in it as well.

Thanks guys.
 

Slow91z

Turbobuick.com Helper
Staff member
I'm a big fan of the seal tabs, never had to use them on a TR but work great on small issues on my daily stuff.
 

turbofabricator

Well-Known Member
Never click your bolts more than one time. You are over torquing them every time you do that. On aircraft, if I click a bolt twice the inspector will require me to remove and replace that fastener/tube. If you want to check torque, back off 1/2 turn and re-torque. and WHY would you torque a head bolt ot 85 ft. lbs??? It is a 7/16" bolt. Factory torque is 65 ft lbs. No gain and probably a bad idea to go that high, unless you have drilled and tapped the block for 1/2" bolts/studs. The ARP thread sealer down in the hole is still plyable afterr 24 hrs, and you are safe to back off and re-torque. That is what I do on head bolts. 4 steps up to 65, then 70 on the two longer bolts. Then let sit 10 minutes and then losen one at a time and a re-torque to full value. Then I am ready to run it. (to qualify the torque sequence, I have literally torqued many hundreds of thousands of bolts on airplanes, boats and cars over the 35 years)
 

Slow91z

Turbobuick.com Helper
Staff member
Not a stock fastener, much stronger material require more torque to stretch. Can't use factory torque spec.
 

David Husek

Turbo Buick Performance
Just put the heads back on my motor. Used stock GM gaskets again and fresh ARPs rated to 200,000psi tensile strength. Torqued to 85 ft. pounds with a brand new torque wrench. They have sat for just about 24 hours as of right now. Will break them loose one at a time tonight and do a final torque.

Do I have to retorque them after a few hundred miles? There seems to be some debate on this subject. Not looking forward to doing this job again any time soon.

Thanks.

Scott
ARP bolts need to be torque at least 3 times to get the yield they recommend with ARP assemble lube and tread sealant. Also you will need to clean the black off the threads before installing for proper torque. Make sure the block threads are chased and clean. I wait 15-20 minutes in between the torque of the bolts. I back off one bolt at a time in sequence a 1/8 of a turn and torque again. No reason to fully relax the fastener.

Arp thread sealer doesn’t dry quickly, so you could torque the bolts again….
 
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