Head gasket re-torque update
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Head gasket re-torque update
Tonight I re-torqued the .027 Cometic head gaskets, which they say, “needs no re-torquing” on their website..
I set my torque wrench, per the AFR website, to 65 lb/ft and went at it,, not a single head bolt clicked on my torque wrench as I loosened the bolts.
So I assume that they were torqued to less than 65 lb/ft or they had all came a little loose. I will call the engine builder tomorrow and ask what they torqued them too.
It only took @ 1 hour to get the headers & y-pipe off, valve covers and RR's then @ 45 minutes to re torque the heads.
Now I will set the RR’s tomorrow night and put the headers back on and clean up the engine bay,,,
I agonized over whether to do this or not and now I feel glad that I did, they may not have leaked but now I feel pretty certain, (hedge) now that they wont leak ( I say while I knock on wood).
:smash: :seeya
I set my torque wrench, per the AFR website, to 65 lb/ft and went at it,, not a single head bolt clicked on my torque wrench as I loosened the bolts.
So I assume that they were torqued to less than 65 lb/ft or they had all came a little loose. I will call the engine builder tomorrow and ask what they torqued them too.
It only took @ 1 hour to get the headers & y-pipe off, valve covers and RR's then @ 45 minutes to re torque the heads.
Now I will set the RR’s tomorrow night and put the headers back on and clean up the engine bay,,,
I agonized over whether to do this or not and now I feel glad that I did, they may not have leaked but now I feel pretty certain, (hedge) now that they wont leak ( I say while I knock on wood).
:smash: :seeya
Le Mans Master
Joined: Mar 2002
Posts: 5,889
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
Re: Head gasket re-torque update (ld85)
This is a good lesson to all of us. We spend tons of dough, work hours on a project......then hedge on an item like this. It doesn't make any sense, but we all do it to some degree or another :crazy:
Good for you Larry :cheers:
Good for you Larry :cheers:
Le Mans Master
Joined: Jun 2002
Posts: 6,097
Likes: 0
From: High Plains Drifter Fayetteville, AR
Re: Head gasket re-torque update (ld85)
Was it a brand new set of heads? Always better to hedge your bets on the side of safety.
If you think it's bad having to retorque smallblock heads, at work when we do a BB build with fresh heads, we have to remove almost all the exhaust rockers. No big deal except they are shaft mounted, what a PITA!
If you think it's bad having to retorque smallblock heads, at work when we do a BB build with fresh heads, we have to remove almost all the exhaust rockers. No big deal except they are shaft mounted, what a PITA!
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Re: Head gasket re-torque update (69vetteracer)
Well on the first engine I bought .021 thick Copper head gaskets, and the SCE tech department told me to use this method. He said to loosen them to determine if they were "too torque" or not, then re-tighten them to spec using the clockwise method starting at the center of head.
I was also told to do this by the tech people at Flatout Gaskets
Yes they were new heads but the ARP head bolts are from the previous builds
I was also told to do this by the tech people at Flatout Gaskets
Yes they were new heads but the ARP head bolts are from the previous builds
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Head gasket re-torque update (ld85)
Do I need to Retorque the Head Gasket Joint?
Yes, we recommend that all copper head gaskets be put through a heat cycle and then retorqued for proper seating of the wire o-ring. The heat cycle should be done with no pressure in the cooling system. Let the engine cool and then retorque. We recommend that the bolt/nut be cracked loose and then retightened to specification following the same torque sequence pattern.
http://www.flatoutgaskets.com/gaskets/techtips.asp
9. Do you recommend a re-torque on head gaskets? Yes, since our gaskets live in the extreme conditions found in High Performance engines, SCE recommends a re-torque on all head gaskets.
http://www.scegaskets.com/techtips/top10.html
[Modified by ld85, 8:24 PM 3/2/2004]
Yes, we recommend that all copper head gaskets be put through a heat cycle and then retorqued for proper seating of the wire o-ring. The heat cycle should be done with no pressure in the cooling system. Let the engine cool and then retorque. We recommend that the bolt/nut be cracked loose and then retightened to specification following the same torque sequence pattern.
http://www.flatoutgaskets.com/gaskets/techtips.asp
9. Do you recommend a re-torque on head gaskets? Yes, since our gaskets live in the extreme conditions found in High Performance engines, SCE recommends a re-torque on all head gaskets.
http://www.scegaskets.com/techtips/top10.html
[Modified by ld85, 8:24 PM 3/2/2004]
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Racer
Joined: Oct 2002
Posts: 416
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From: Westfield MA
Re: Head gasket re-torque update (ld85)
I congratulate you on taking the time to do the job right. I just want to mention something about "clicker" type torque wrenches. I work on aircraft for a living and we use torque wrenches on just about every single fastener on the aircraft. Our torque wrenches go back to the metrology lab for calibration checks every 90 days or IMMEDIATELY if they get dropped from any height. You'd be surprised how far out of calibration a good torque wrench can be if it gets dropped onto the hangar floor. Also, not all "clicker" type torque wrenches are designed to maintain accuracy in both clockwise and counterclockwise direction. Some are only accurate in one direction. Most "Snap On" wrenches are accurate to 2% in either direction. Some of our older "Proto" brand wrenches are not and are marked as such. Just something to think about -----------. Most torque wrench manufacturer web sites will list the accuracy of their products and if it applys to "both" directions.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Head gasket re-torque update (SS409 425HP)
Scorp, I agree it does take less, but I could tell when I loosened them that they were not even close, a couple of them"cracked' loud when they came loose but the rest made me really wonder what torque setting they used. I will find out tomorrow
:iagree: I sell DC Torque & Angle control systems that start at $25K and go up,, so I understand what you mean, we measure torque in minutes of degrees
I borrowed the engine builders Snap On brand torque wrench the first time to compare with mine and they were very close to each other,
If Iever do this again I wil lbuy the new Crafstman electric torque reading transducer, I almost got it this time but decided against it :seeya
I congratulate you on taking the time to do the job right. I just want to mention something about "clicker" type torque wrenches. I work on aircraft for a living and we use torque wrenches on just about every single fastener on the aircraft. Our torque wrenches go back to the metrology lab for calibration checks every 90 days or IMMEDIATELY if they get dropped from any height. You'd be surprised how far out of calibration a good torque wrench can be if it gets dropped onto the hangar floor. Also, not all "clicker" type torque wrenches are designed to maintain accuracy in both clockwise and counterclockwise direction. Some are only accurate in one direction. Most "Snap On" wrenches are accurate to 2% in either direction. Some of our older "Proto" brand wrenches are not and are marked as such. Just something to think about -----------. Most torque wrench manufacturer web sites will list the accuracy of their products and if it applys to "both" directions.
I borrowed the engine builders Snap On brand torque wrench the first time to compare with mine and they were very close to each other,
If Iever do this again I wil lbuy the new Crafstman electric torque reading transducer, I almost got it this time but decided against it :seeya
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Re: Head gasket re-torque update (ld85)
Scorp, I agree it does take less, but I could tell when I loosened them that they were not even close, a couple of them"cracked' loud when they came loose but the rest made me really wonder what torque setting they used. I will find out tomorrow
I congratulate you on taking the time to do the job right. I just want to mention something about "clicker" type torque wrenches. I work on aircraft for a living and we use torque wrenches on just about every single fastener on the aircraft. Our torque wrenches go back to the metrology lab for calibration checks every 90 days or IMMEDIATELY if they get dropped from any height. You'd be surprised how far out of calibration a good torque wrench can be if it gets dropped onto the hangar floor. Also, not all "clicker" type torque wrenches are designed to maintain accuracy in both clockwise and counterclockwise direction. Some are only accurate in one direction. Most "Snap On" wrenches are accurate to 2% in either direction. Some of our older "Proto" brand wrenches are not and are marked as such. Just something to think about -----------. Most torque wrench manufacturer web sites will list the accuracy of their products and if it applys to "both" directions.
:iagree: I sell DC Torque & Angle control systems that start at $25K and go up,, so I understand what you mean, we measure torque in minutes of degrees
I borrowed the engine builders Snap On brand torque wrench the first time to compare with mine and they were very close to each other,
If Iever do this again I wil lbuy the new Crafstman electric torque reading transducer, I almost got it this time but decided against it :seeya
I congratulate you on taking the time to do the job right. I just want to mention something about "clicker" type torque wrenches. I work on aircraft for a living and we use torque wrenches on just about every single fastener on the aircraft. Our torque wrenches go back to the metrology lab for calibration checks every 90 days or IMMEDIATELY if they get dropped from any height. You'd be surprised how far out of calibration a good torque wrench can be if it gets dropped onto the hangar floor. Also, not all "clicker" type torque wrenches are designed to maintain accuracy in both clockwise and counterclockwise direction. Some are only accurate in one direction. Most "Snap On" wrenches are accurate to 2% in either direction. Some of our older "Proto" brand wrenches are not and are marked as such. Just something to think about -----------. Most torque wrench manufacturer web sites will list the accuracy of their products and if it applys to "both" directions.
:iagree: I sell DC Torque & Angle control systems that start at $25K and go up,, so I understand what you mean, we measure torque in minutes of degrees
I borrowed the engine builders Snap On brand torque wrench the first time to compare with mine and they were very close to each other,
If Iever do this again I wil lbuy the new Crafstman electric torque reading transducer, I almost got it this time but decided against it :seeya
Jake
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Head gasket re-torque update (JAKE)
Spoke to the builder just now, they torqued them to 65 lb/t on the long bolts and 60 lb/ft on the short bolts.
I know for fact that they were not at 65 lbs, so I guess for me the extar concern and effort paid off...
tax, tag and title not included, prices and your mileage may vary in your state, void where prohibited, what else??? :lol: :lol: :leaving:
I know for fact that they were not at 65 lbs, so I guess for me the extar concern and effort paid off...
tax, tag and title not included, prices and your mileage may vary in your state, void where prohibited, what else??? :lol: :lol: :leaving:
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: Head gasket re-torque update (ld85)
If it were me I would not have loosened them as I feel that shows false readings. I would have just attempted to tightened them to spec in the proper torquing pattern and if the wrench clicked w/o movement I'd have been happy.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
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From: seattle WA
Re: Head gasket re-torque update (JAKE)
This has been a hot topic in the past, whether to re-torque or not. As an old shade tree mech. I was taught to always re-torque.And I always did.Some argued re-torquing wasn't necessary because of new gasket technology :skep: But I concur, with the time and money we invest, this simple chore sure gives one a little added insurance and a big piece of mind knowing our investment has properly been torqued. :) :seeya
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
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From: Indianapolis IN
Re: Head gasket re-torque update (scorp508)
If it were me I would not have loosened them as I feel that shows false readings. I would have just attempted to tightened them to spec in the proper torquing pattern and if the wrench clicked w/o movement I'd have been happy.
