Cometic's leaking

[TURBOGTA1]

Just got the car running after installing a new set of GN1's with cometic
gaskets, ARP bolts, and coolant leaking slightly from each head onto exhaust. I sprayed a layer of copper spray on each side of gasket, torqued them down,waited overnite, backed off slightly and retorqued them again the next day. I am going by Champion's spec of 75 ft pounds for top bolt's, and 65 for the lower's. Not sure about this seeing a lot of people on the board using 75-85 for all. I also used 2 GM tablets. Ive had the car running for about 1.1/2 hour, but have not taken it for a ride yet!! Any help would be appreciated!!!

 

[Russ Merritt]

Give it a day. Let it cool all the way down and tomorrow when you start it check again. If it still leaks, another 2 tablets won't hurt anything. I torque them tighter to compensate for settling as I don't retorque.

 

[chazmat2316]

Give it some time they will stop! been there!!!!!!!

 

[galoush]

not claiming to be an expert ( My Friend calls me Neanderthal racing ) but , Did you wire wheel the bolts ? I retourqued mine 3X New bolts and gaskets . I dont think the copper should have been used on the gaskets . I have them on my car with GN1s and they have been good so far , id throw in a few more of the GM tabs and see . Good luck , youll get it worked out

 

[CTX-SLPR]

ARP suggests retorquing bolts 5 times and with head bolts especially I'd run it up to temp a few times then retorque another 2-3 times to make sure the gasket is fully crushed and expanded. Also MLS style gaskets have been known to leak between the layers sometimes. If it don't quit after retorquing and breakin cycling, pull them and drill the rivets and pull the layers apart gently and spray the layers lightly with I think its copper or halomar (please do a search on that as its all memory) But this has been covered before.

 

[slipstick]

I used Cometics in my rebuild which now has approx 700 miles. I used radiator tablets and never had a coolant leak. However, I do have oil leaks on both sides of the block which appears to be coming from head gaskets. I know there is no oil pressure sealing points in this area. I have changed the rocker cover gaskets and checked the intake manifold to block seal. The leaks appear to be at the head gaskets. Anyone else with similar experience?????

 

[DonnieShort]

I used Cometics in my rebuild which now has approx 700 miles. I used radiator tablets and never had a coolant leak. However, I do have oil leaks on both sides of the block which appears to be coming from head gaskets. I know there is no oil pressure sealing points in this area. I have changed the rocker cover gaskets and checked the intake manifold to block seal. The leaks appear to be at the head gaskets. Anyone else with similar experience?????

Check the valve cover gaskets, mine did the same thing (on a new motor ) and wound up needing better gaskets.

 

[TURBOGTA1]

not claiming to be an expert ( My Friend calls me Neanderthal racing ) but , Did you wire wheel the bolts ? I retourqued mine 3X New bolts and gaskets . I dont think the copper should have been used on the gaskets . I have them on my car with GN1s and they have been good so far , id throw in a few more of the GM tabs and see . Good luck , youll get it worked out

Bolt's were wire wheeled. Is everyone using the Champion torque spec of 75/top, and 65/bottom !!!

 

[jjvites]

I used Cometics in my rebuild which now has approx 700 miles. I used radiator tablets and never had a coolant leak. However, I do have oil leaks on both sides of the block which appears to be coming from head gaskets. I know there is no oil pressure sealing points in this area. I have changed the rocker cover gaskets and checked the intake manifold to block seal. The leaks appear to be at the head gaskets. Anyone else with similar experience?????

Years go I had the exact same problem with leaking oil from the head gaskets. No matter how hard I looked with a mirror it seemed like it was from the head gaskets. Well there is no oil between head and block, so after removing the intake there was the evidence. It is extremely difficult to actually see it leaking as it could be very slow and hard to see back there and where it finally runs dow the block it looks like the heads. Back of block where intake meets the cylinder head. Sealed well with Fel Pro Silicone and 8 years later no oil leaks.

Marty

 

[lrayzer]

I concurr, the VC gaskets and intake have to be the source, RTV seal for the intake and the new felpro metalcore gaskets for the VC ( blue rubber ) will solve the problems with oil leaks.

As for the coolant....
Did you lube the threads before torquing and retap the bolt holes to clean ?
This should always be done, you will see 5 to 10 ft lbs difference in torque readings, when in doubt I go up in 5 lb increments until they feel right ( and quit leaking ) is the block surface flat ? how did you prep it for gasket install ?

 

[Razor]

I sprayed mine between the layers, tq'd them to 85.. so far 2.5 months, 50 passes.. no issues. Used 2 tabs for insurance..

I was told not to spray them, I was told to TQ them to 75, I was told they would leak... guess I showed them :wink:

 

[TURBOGTA1]

I sprayed mine between the layers, tq'd them to 85.. so far 2.5 months, 50 passes.. no issues. Used 2 tabs for insurance..

I was told not to spray them, I was told to TQ them to 75, I was told they would leak... guess I showed them :wink:

Took it out for a couple of drive's, leaking less than before, guess ill pull the header's/cover's and bring up the torque!!! only torqued to 65/75

 

[vacuum 6]

Took it out for a couple of drive's, leaking less than before, guess ill pull the header's/cover's and bring up the torque!!! only torqued to 65/75

How did things turn out? Yep I have the same problem, my cometics are weeping too.

 

[6bangr]

What kind of coolant? Evans is supposed to be "slipperier" and alot harder to keep sealed if the engine is not built or sealed in the proper bolt-stud locations.

 

[vacuum 6]

Proline 50/50 from Pepboys.

 

[turbofabricator]

Another consideration for weeping gaskets might be the machine finish on the block and heads. It needs to be darn near mirror finish. IF you use them on a stock deck finish, they will (supposedly) leak.

 

[my1stgn]

Wow? Another Cometic Head Gasket Leak?...... Has someone contacted the company yet? Last time I spoke with them (they are useless anyways) they said the gaskets (by design) go on dry (ie no Hylomar or Copper Spray) and to send them back the "faulty" gaskets to get a new and imporved set........ 6 1/2 years later, I havent recieved these "improved" gaskets..........

 

[wheelie]

I used Felpro MLS on the Ford stuff, but I have used Cometics as well. On the multi-layer gaskets, I use copper coat, and spray it in between the layers, and on the top and bottom, just like a copper head gasket. We let it get tacky, then install it and torque. Havent had much problems over past 4 years, with 32-38psi boost, and agressive timing on our race cars.