If I remember right they all took a 1/4 turn or less, but again took some. 3 years of 25psi or better without any issue.
"The stuff is thick, it takes a while to find its way out" Sounds like my house on a Friday night!!!
Headgasket installation with Studs
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If I remember right they all took a 1/4 turn or less, but again took some. 3 years of 25psi or better without any issue.
"The stuff is thick, it takes a while to find its way out" Sounds like my house on a Friday night!!!
Actually it is a sealant...that's what GM used from the factory to seal the TTY head bolt threads...and front cover bolts that go into water jackets...I use GM teflon sealant for heads stud threads...front cover bolts...fuel line connections...oil line connections...etc...works great on just about any connection you want to seal...
x2 I used it too
Don't want to get in an argument, But
Why would you use it on fuel and oil lines that have an o-ring for sealing. Unless you feel that the nuts run on easier--in which case you just proved my point. I used to use Loctite liquid teflon but found that it set up some what when heated. The teflon is for NPT threads which have a taper--that is the way they seal the tighter you can run them the better chance for sealing. You guys use whatever you prefer--for me I will use teflon on NPT threads and Silicone sealant on head studs. Over and out of here.
Why would you use it on fuel and oil lines that have an o-ring for sealing. Unless you feel that the nuts run on easier--in which case you just proved my point. I used to use Loctite liquid teflon but found that it set up some what when heated. The teflon is for NPT threads which have a taper--that is the way they seal the tighter you can run them the better chance for sealing. You guys use whatever you prefer--for me I will use teflon on NPT threads and Silicone sealant on head studs. Over and out of here.
turbodave231
Moderator
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The factory did NOT use GM pipe sealer with Teflon on TTY head bolts.
Go buy a new GM TTY bolt and look at it. It has an orange pre-applied patch on the bolt. The special sealant was pre-applied to the threads and under the bolt heads.
The head bolt engineers allowed one re-use of the bolt and specified the GM pipe sealant with teflon when bolts were to be re-used........ and true, it works great on the TTY head bolts.
From my personal experience, GM pipe Sealer with Teflon does not work too well on head studs. I have assembled several different engines with GM pipe sealant w/teflon on the head studs where they thread into the block. I've have had weepage up the head studs into the valve cover area every time I've used it. I have mostly eliminated this problem on my engine builds by using Permatex Ultra black RTV in place of the Pipe thread sealant.
Don't ask me why sealing head studs are any different than bolts........but trust me, they are!!!!
This subject has been beat to death in the past.......just thought I'd take one more kick at it for the newbies.
Dave
I can't argue with that Jay. You are the Man........That saves us all some work. My engine is still out and I will follow your advice about the Re-Torquing ..........BTW...... you guys are doing an AWESOME Job with the Twins!!!
............Thanks for straightening out the Re-Torquing Questions.Another thing, you have to torque cycle the new head studs. They have to "stretch" to attain the proper clamping force. I torque cycle them 5x. I loosen them a 1/4 turn and torque them.
You can not re-torque the fasteners without loosening them. It takes more torque to break a fastener loose than it was previously torqued to.
+1 on the black RTV.
Billy T.
gnxtc2@aol.com
You can not re-torque the fasteners without loosening them. It takes more torque to break a fastener loose than it was previously torqued to.
+1 on the black RTV.
Billy T.
gnxtc2@aol.com
turbo nasty
Turbo Dojo / MNTR
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Everyone has their own short cut/sealant/etc
I prefer Permatex #2 on the studs as it stays pliable and is non hardening and very resilient
As Jay stated after they have sat for several hours retorque.
Back off the nut and then with a smooth/steady even pull on the torque wrench, tighten to your retorque spec.
Use same smooth pull retorque method on all
I prefer Permatex #2 on the studs as it stays pliable and is non hardening and very resilient
As Jay stated after they have sat for several hours retorque.
Back off the nut and then with a smooth/steady even pull on the torque wrench, tighten to your retorque spec.
Use same smooth pull retorque method on all
first off, if you grind a little on the header flange when you have the heads off so you can get your socket on the head stud nut, you do not have to take anything off except the valve covers to do a full retorque. It literally can be done in less than 1/2 hour.
We would not put in the instructions "retorque after heat cycles is the most important step if it was not. If you did not have to do it then we would not mention it.
Here is our take on this post so far. Retorquing a couple of hours after initially torquing the gaskets is an excellent idea for the reasons Jay stated. So is cycling the head stud as stated by billy T. Taking the black oxide coating off the stud is not necessary and actually the micro pourus surface created makes the silicon sticks better if you leave it on and just degrease it. If you don't believe me just do a little test on the bench, polish one set of threads and leave the other one alone, coat with silicon, let dry and then try and clean the silicon off. It will become obviously apparent.
Teflon thread sealer seems to work very well as a lubricant and a sealer. We silicon the head stud in and then use the teflon thread sealant on the fine threads and under the washer for a second sealing of the head stud.
A little bit about our gaskets. Our gaskets are made from 304 stainless steel. they are similar to but not exactly like the 84-85 factory steel shim head gaskets that were made from mild steel. Our gaskets have sealing ridges stamped into the stainless sheet after we laser cut them out. These ridges are placed in strategic places to seal combustion, water and oil and are there to distribute load in the proper places adding pressure where we need it most, right around the combustion chamber. We have changed the gasket several times to aid in areas that we have found weak spots in the original design.
Also over the years we have discovered several things that happen when you run the gaskets and how they react while in service. Now let us explain to you why you have to torque the bolts after some heat cycles. Our head gaskets do not crush completely flat. They "crush" about .015 during initial assembly but leave another .015 of ridge that is not compressed. they are designed so that the ridges are continually adding pressure to seal around the combustion chamber. They also have a memory which means that they are flatter when installed than when you loosen the bolts and take them out after service. This helps them to seal if you do lift the head under extreme cylinder pressure.
during the initial torquing or during a normal heat cycle. things do not warm up and expand at equal rates. the block heats up first then the heads and lastly the fasteners, (ie head studs or bolts). everything grows at different rates and this affects the remaining ridges in the gasket. as the head, block, gasket and studs grow and shrink several things happen. the fastener find their "seat", that is the point at which they are the most relaxed after settling past any imperfections in seating surface, thread engagement, etc. Next as the head grows length wise and in thickness where it adds additional pressure on the head gaskets ridges causing them to compress slightly more. Since our goal is to have the most pressure possible between the head and the block. This is why when you retorque the nuts tighten. To compensate for this additional compression retorquing after a few of these cycles is necessary. If your heads are aluminum the thermal expansion rate of aluminum is so much more than cast iron that it compounds the situation.
Keep in mind, this "thermal crushing" of the gasket is occurs with ALL gaskets not just ours.
Once this is done you have a seal that is very very strong. There is a lot more to it than "we bolted it on and it worked fine for us". The weakest link on these Buicks is the head gasket seal. Why would you not want to do everything you can to reduce this weakness as much as possible? isn't this why you bought the bullet proof head gaskets in the first place?
Can you get away with not doing the retorque after a heat cycle? surely, and you might have years of trouble free service. At least now you are educated in why it is recommended and can weigh that into your decision. it all depends on how much cylinder pressure you are trying to contain.
The cometics only have a rib primarily around the combustion chamber so they work pretty well at sealing combustion like ours but have problems with the water and oil.
We are continually improving on the head gasket set, with different bore sizes, ridge design and sealant. Recently, we have been experimenting with a different type of sealant that so far in our testing seems to be an improvement.
sorry it is so lengthy.
We would not put in the instructions "retorque after heat cycles is the most important step if it was not. If you did not have to do it then we would not mention it.
Here is our take on this post so far. Retorquing a couple of hours after initially torquing the gaskets is an excellent idea for the reasons Jay stated. So is cycling the head stud as stated by billy T. Taking the black oxide coating off the stud is not necessary and actually the micro pourus surface created makes the silicon sticks better if you leave it on and just degrease it. If you don't believe me just do a little test on the bench, polish one set of threads and leave the other one alone, coat with silicon, let dry and then try and clean the silicon off. It will become obviously apparent.
Teflon thread sealer seems to work very well as a lubricant and a sealer. We silicon the head stud in and then use the teflon thread sealant on the fine threads and under the washer for a second sealing of the head stud.
A little bit about our gaskets. Our gaskets are made from 304 stainless steel. they are similar to but not exactly like the 84-85 factory steel shim head gaskets that were made from mild steel. Our gaskets have sealing ridges stamped into the stainless sheet after we laser cut them out. These ridges are placed in strategic places to seal combustion, water and oil and are there to distribute load in the proper places adding pressure where we need it most, right around the combustion chamber. We have changed the gasket several times to aid in areas that we have found weak spots in the original design.
Also over the years we have discovered several things that happen when you run the gaskets and how they react while in service. Now let us explain to you why you have to torque the bolts after some heat cycles. Our head gaskets do not crush completely flat. They "crush" about .015 during initial assembly but leave another .015 of ridge that is not compressed. they are designed so that the ridges are continually adding pressure to seal around the combustion chamber. They also have a memory which means that they are flatter when installed than when you loosen the bolts and take them out after service. This helps them to seal if you do lift the head under extreme cylinder pressure.
during the initial torquing or during a normal heat cycle. things do not warm up and expand at equal rates. the block heats up first then the heads and lastly the fasteners, (ie head studs or bolts). everything grows at different rates and this affects the remaining ridges in the gasket. as the head, block, gasket and studs grow and shrink several things happen. the fastener find their "seat", that is the point at which they are the most relaxed after settling past any imperfections in seating surface, thread engagement, etc. Next as the head grows length wise and in thickness where it adds additional pressure on the head gaskets ridges causing them to compress slightly more. Since our goal is to have the most pressure possible between the head and the block. This is why when you retorque the nuts tighten. To compensate for this additional compression retorquing after a few of these cycles is necessary. If your heads are aluminum the thermal expansion rate of aluminum is so much more than cast iron that it compounds the situation.
Keep in mind, this "thermal crushing" of the gasket is occurs with ALL gaskets not just ours.
Once this is done you have a seal that is very very strong. There is a lot more to it than "we bolted it on and it worked fine for us". The weakest link on these Buicks is the head gasket seal. Why would you not want to do everything you can to reduce this weakness as much as possible? isn't this why you bought the bullet proof head gaskets in the first place?
Can you get away with not doing the retorque after a heat cycle? surely, and you might have years of trouble free service. At least now you are educated in why it is recommended and can weigh that into your decision. it all depends on how much cylinder pressure you are trying to contain.
The cometics only have a rib primarily around the combustion chamber so they work pretty well at sealing combustion like ours but have problems with the water and oil.
We are continually improving on the head gasket set, with different bore sizes, ridge design and sealant. Recently, we have been experimenting with a different type of sealant that so far in our testing seems to be an improvement.
sorry it is so lengthy.
turbo nasty
Turbo Dojo / MNTR
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- Jul 19, 2001
- Messages
- 9,478
Great Vendor input. Keep up the good work Jason
getchasum
MISSING 2 CYLINDERS???
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- May 23, 2002
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- 2,280
Just rambling here & really just trying to find which way I’m going w/ my new build….
I’ve only got 3 builds under my belt and have used the GM Teflon Paste. Every time I’ve experienced some seepage up the stud coming out around the nut/washer. (My process was to clean, clean, clean & clean, apply an even coat of the Teflon paste on threads, let it set 24 hrs, install head, torque heads, then re-torque in several hrs) I’ve had to cured the seepage with the GM sealant tabs. So the next build I plan to use the Permatex ultra black.
Is it not a concern of anyone’s that if you wait to long to re-torque the heads or after a heat cycle that you will compromise the seal between the head studs and the block treads & get coolant leakage? (I understand that the teflon paste is a lube base sealant so waiting 24 hrs to install the head was not a concern)
I’ve only got 3 builds under my belt and have used the GM Teflon Paste. Every time I’ve experienced some seepage up the stud coming out around the nut/washer. (My process was to clean, clean, clean & clean
, apply an even coat of the Teflon paste on threads, let it set 24 hrs, install head, torque heads, then re-torque in several hrs) I’ve had to cured the seepage with the GM sealant tabs. So the next build I plan to use the Permatex ultra black.Is it not a concern of anyone’s that if you wait to long to re-torque the heads or after a heat cycle that you will compromise the seal between the head studs and the block treads & get coolant leakage? (I understand that the teflon paste is a lube base sealant so waiting 24 hrs to install the head was not a concern)
When I did my head gaskets last year I focused on getting everything perfectly clean first. I used stock gaskets and assembled the studs using GM thread sealer #12346004. I torqued the heads to around 75lbs then put two HEAT GUNS up to the water ports until the heads were to hot to touch. Torqued to 85lbs. Let it cool. Reheated heads. Cooled again and rechecked. So far so good. If I have a gasket let go now, I think it will be from uneven deck surface. Motor has been apart twice since rebuild. First for head gasket and second time for TB screw fell in motor.
I don't think the studs will move enough to matter on retorque, to ruin the seal, head bolts is a different story, I would worry more about them. I use the High Temp Permatex, Its the replacement for Loctite 567.
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- Feb 18, 2006
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Rock-N-Roll!
What a great thread! We have some real good information here. Great procedures that all come from people who are well respected. I love the info, I LOVE IT! :biggrin:
Thanks to all who posted!
I'm makin a sticky.
What a great thread! We have some real good information here. Great procedures that all come from people who are well respected. I love the info, I LOVE IT! :biggrin:
Thanks to all who posted!
I'm makin a sticky.
X2 on Otto ... Go in sequence 5 times, it's a turbo. Always did my BBC's four times, 20lbs, 40lbs, 60lbs, and the final torque ( 85lb on my BBC ) so whatever your head number asked for, I think I saw 80lbs a few post back.
Don't forget the cleaner the better, I use brake clean..squirt in each stud location and let sit a min or two, cover with shop rag and blow out. Yes you have to be careful, but gets the job done. Never had puddles of oil seeping up on the intake using this method. Sealer I agree is up to your choice. I use blue RV.
No good luck needed, just take your time.
Don't forget the cleaner the better, I use brake clean..squirt in each stud location and let sit a min or two, cover with shop rag and blow out. Yes you have to be careful, but gets the job done. Never had puddles of oil seeping up on the intake using this method. Sealer I agree is up to your choice. I use blue RV.
No good luck needed, just take your time.
i managed to buy about 20 stock gaskets before they were discontinued. i used the same method as RJC, i now need to switch the heads to another block. is the GE 1200 still available? years ago i got it from fastenal,tried to get some today and they said they can't get it. is the green label 1200 the same as the purple one? thanks
turboc87gn
Darkside in Detroit
- Joined
- Oct 2, 2008
- Messages
- 2,766
So when you do the retorque if you loosen them a quarter turn do you go back thru the 4-5 steps of torquing them or do you loosen them a quarter turn then tighten back to max torque?
GARY HARVEY
Member
- Joined
- Aug 17, 2001
- Messages
- 444
SS502 had an excellent tutor.
You can't be too anal with fastener preparation. After using your preferred cleaner, I follow-up with grain alcohol (if it's good enough for NASA, it's good enough) and if there's anything left in the bottle, you can always find some OJ.
Copper coat sprayed on the cylinder head side of the gasket and the block surface with one coat is another step I use, letting it dry in place for a day or so is good and gives you a chance to remember if you screwed something up..
As for the loosen and tighten step, I follow this procedure on the first series of
torque passes, leaving the final pass in place and re-torque after a few cycles if
you have a chance (not loosening) the final torque pass.
ARP studs, washers and fine threaded nuts leave little room for error.
You can't be too anal with fastener preparation. After using your preferred cleaner, I follow-up with grain alcohol (if it's good enough for NASA, it's good enough) and if there's anything left in the bottle, you can always find some OJ.
Copper coat sprayed on the cylinder head side of the gasket and the block surface with one coat is another step I use, letting it dry in place for a day or so is good and gives you a chance to remember if you screwed something up..
As for the loosen and tighten step, I follow this procedure on the first series of
torque passes, leaving the final pass in place and re-torque after a few cycles if
you have a chance (not loosening) the final torque pass.
ARP studs, washers and fine threaded nuts leave little room for error.
I have a couple of points here...
As for teflon paste, I used it for years, had some seepage issues.
I tried other things and had great sucess but cleanup for reuse was a pain.
DLS mentioned he used ultra Black and I have since started using it on head studs and bolts and rear main seals. Stuff is great.
My point is Brake cleaner, its not all created equal.
some will leave a film that will hinder proper sealing.
for this reason Caterpillar required us Techs to clean all critical sealing points with electical contact cleaner.
I also use Methyl alcohol with great sucess if I have no contact cleaner.
Watch what you clean your Block and heads with.
As for teflon paste, I used it for years, had some seepage issues.
I tried other things and had great sucess but cleanup for reuse was a pain.
DLS mentioned he used ultra Black and I have since started using it on head studs and bolts and rear main seals. Stuff is great.
My point is Brake cleaner, its not all created equal.
some will leave a film that will hinder proper sealing.
for this reason Caterpillar required us Techs to clean all critical sealing points with electical contact cleaner.
I also use Methyl alcohol with great sucess if I have no contact cleaner.
Watch what you clean your Block and heads with.
