OK guys, its about that time on my build and its something ive been worried about for awhile now. definitely need to get this answered for sure...
Am I supposed to drill the rivets of my LD9 Cometic head gasket then spray each layer with copper spray, or not? ive heard mixed reviews, some say hell yes spray that bish, others just install and never have an issue.
Both my head and block and been decked and checked, they are 100% perfectly true and straight so that factor is out of the equation. The gasket of choice is an .030 thick "N/A" multi-layer steel unit. ARP head studs will also be used.
Ive heard Cometic says no, do not do it. That is pretty much the only reason why i am asking....
Edited 1 time(s). Last edited Wednesday, May 12, 2010 9:17 PM
Don't know what ya got til they take it away...
My personal experiences with COmetic gaskets.
#1:
Installed with no alterations done to it. Ran fine for 1500 miles without any issues, then a wrist pin retainer came out and I had to rebuild.
#2:
Installed on a fresh rebuild, no alterations done to it. After 200 miles coolant was coming out between the layers. No coolant leaking between the head or block and gasket, but from between the individual layers. Head studs were torqued to 75 ft-lbs.
#3:
Installed to replace the previous gasket. Assumed it may have been some error in manufacturing, so this one went in as is. After 200 miles it leaked between the layers again. Head studs were torqued to 80 ft-lbs per Cometic reccomendation.
#3 attempt 2:
Called Cometic. Was told it was a surfacing issue with my parts, not to use any kind of sealant as it would only cause a leak, and that there was nothing wrong with their parts (not sure how they knew this as I still had both in my posession). They refused to believe that there was any way that the gasket could leak between the layers. Out of frustration I took teh gasket to work and drilled out the rivets. there is nothing between the layers to seal them. I decided that the worst that could happen was that the gasket would leak again, so I used copper spray on both sides of each layer. Even though Cometic insisted it would cause a leak, it @!#$ worked. After pulling the head 3 weekends in a row I was fed up. The copper spray treated one lasted till I pulled apart the engine after a melt down (over 16k miles after install).
#2 used second time:
Just recently did the HG on my 02 and reused the second Cometic HG. Once again I drilled the rivets and used copper spray (about a cans worth, it was a windy day) and then installed. It has been about 3k miles since and still no signs of leakage. I dont even know if this block is perfectly true as it has over 200k on it and I didnt really care.
My personal experience says to coat both sides of each layer as a precaution.
i ditched the cometic and went with an OEM GM Gasket...
Do not drill out the rivets.
I used light spray copper when I installed my MLS gasket on both sides. I did not spray between layers.
When i talked to Cometic they recommended to install them dry, but the old men at the machine shop recommended that I DO spray it lightly since it is multi layered. That's what I did and no problems after a year yet.
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
kyle- why?
david - didnt you have a head gasket pop after ur first build?
Don't know what ya got til they take it away...
Brad, my turbo engine used a stock gasket as I didnt want to deal with a Cometic. I used a Cometic in my 02 when I replaced the HG because I had one laying around and didnt feel like buying a new stocker. Same reason I have head studs in that engine.
Yea thats because my car overheated because my GRIFFEN radiator was crushed without me knowing. That would of happend to any gasket.
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
you need the surface on the head and the block smooth as possible, like a mirror finish
Location: Montreal, Quebec
dave- lol wow i did not know that. was that a griffen issue or something you did?
mcmoney- do you mean that for with or without copper spray? what did you do?
Don't know what ya got til they take it away...
I dont use any sealant and I'm fine for now
Location: Montreal, Quebec
I didn't use spray and my motor has bee together for going on at least 5yrs now
R.I.P. Brian Klocke, you will never be forgotten
I suspect that my issues were a manufacturing flaw as both gaskets that leaked were manufactured in the same run. My first one had no issues at all, but number 2 and three did. Before anyone claims its the surfaces on my parts, the head and block were the same for all gaskets and no coolant leaked from between the engine components and gasket.
Screw-it! Just get a Fel-pro "Blue" with the fire-ring & be done with it!
Go beyond the "bolt-on".
I wont use a Fel Pro after all the failures I have come across. Factory graphite is my preferance if I am buying a new gasket.
Bumping this back up for reference for the future.
First build was with a Fel-Pro gasket and Fel-Pro bolts torqued to stock spec (I think it's something like 40 lb-ft). After 5,000 miles of moderate boost, the gasket leaked coolant into cylinder one severely after some tuning runs @ 14 psi from a Garrett T3 50 trim .48/.42 turbocharger.
Replaced that head gasket with a factory GM gasket along with ARP head studs torqued to 75 lb-ft. After 10,000 miles of moderate boost from the same turbo and then 18 psi from the GT3076R, it finally became significantly noticeable that the head gasket was leaking into cylinder 1 again. The car has been having odd vibration/stumbling upon startup, and today I discovered that was due to coolant burning off in cylinder 1. Explains a lot of things that have been going on with the car... so fun @!#$.
This time I'm ordering a Cometic and using the same ARP studs, as well as ensuring the head is perfectly flat and roughness is satisfactory. Hopefully that holds up to my measly 18 psi boost pressures.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
[ion wrote: C2]Bumping this back up for reference for the future.
First build was with a Fel-Pro gasket and Fel-Pro bolts torqued to stock spec (I think it's something like 40 lb-ft). After 5,000 miles of moderate boost, the gasket leaked coolant into cylinder one severely after some tuning runs @ 14 psi from a Garrett T3 50 trim .48/.42 turbocharger.
Replaced that head gasket with a factory GM gasket along with ARP head studs torqued to 75 lb-ft. After 10,000 miles of moderate boost from the same turbo and then 18 psi from the GT3076R, it finally became significantly noticeable that the head gasket was leaking into cylinder 1 again. The car has been having odd vibration/stumbling upon startup, and today I discovered that was due to coolant burning off in cylinder 1. Explains a lot of things that have been going on with the car... so fun @!#$.
This time I'm ordering a Cometic and using the same ARP studs, as well as ensuring the head is perfectly flat and roughness is satisfactory. Hopefully that holds up to my measly 18 psi boost pressures.
my felpro leaked at 14lbs too... cometic with arp studs tq'd to 85lbs held 25psi of gt35r fury
R.I.P. Brian Klocke, you will never be forgotten
Good to hear. Ordering the gasket now, can't wait to tear this down and get it the heck back on the road ASAP.
I'll torque my studs to 85 lb-ft too. What did you torque the small bolts under the timing cover to?
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
Using cometic with copper spray (with the rivets drilled!) on my 3800... not one issue.
i am impressed.
definitely will be looking into SCE for future builds.
total win SLOWzee!
I feel like taking a tinkle on an ecNOtec...
Nice find SLOWZEEE..
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
Wow, very nice find, and thanks for the link!
PRND321 Till I DIE
Old Motor: 160whp & 152ft/lbs, 1/4 Mile 15.4 @88.2
M45 + LD9 + 4T40-E, GO GO GO
Same brand of head gasket i ran on my 92 turbo saturn, never had not one single problem out of it....I blew 4 fel pro blues before buying one of these...These are absolutely the best head gaskets on the market right now.....and the price isnt all that unreasonable
I used a SCE on my old Talon with no issues. That was prior to o-ringing the block and using Mitsubushi MLS gaskets.
"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"
[ion wrote: C2]I'll torque my studs to 85 lb-ft too. What did you torque the small bolts under the timing cover to?
Quoted for answer request. That might be the reason my current one blew in the same area on Cylinder 1. Those shorter bolts on the timing cover side, not sure what spec to torque them to.
2001 Olds Alero (LD9)
650 whp / 543 ft-lb
@turboalero
