Cometic Head Gaskets LEAKING!

[soontobefastfox]

Okay I built a myself a 331 and I got it fired up in the summer (almost 2 years of working on it...). I got it dyno tuned and it laid down 360 rwhp 370 rwtq (100% street car, N/A is setup for a supercharger). But the problem is after awhile of diagnoising the problem (my coolant temperature was a little higher than I wanted it to be, it would hang around 195-200 with a 185 t-stat.). I found the problem, the head gaskets are not leaking out in the engine compartment, but inside the exhaust valve (steam comes out of the exhaust pipes), its very strange I checked my oil to see if there was any coolant in the oil, but there isn't a drop. This **** sucks, I drove my stang 120 miles and now I gotta play with the head gaskets.

Oh I torqued the heads once already and I am going to try again before I take the heads off and replace these POS cometic head gaskets with some Fel Pro MLS. The worst part is the problem could have been avoided if I went with my gut feeling I believe. I called cometic about spraying their gaskets with the copper spray and said not to.

Just wondering if anyone had any experiences like mine.

 

[BlownFiveLiter]

Shoot a PM to gcomfx.com, he's a member in 94-95 that just had the same problem with his Cometic gaskets on a new 331 earlier this year. I don't recall what the solution was off hand, but he'll definitely have the details for ya.

 

[soontobefastfox]

Ok thanks, I sent gcomfx.com a PM.

 

[gcomfx.com]

My problem starts at post 90. You can read all about as it happened. LOL I even have a video of the leak.

http://forums.stangnet.com/showthread.php?t=688786&page=4

Highlights:

"Engine builder spoke with Cometic. They are working on a new gasket for our engines. It's a problem with the thickness and the material inside. They have a sealer they will be adding to them soon. In the mean time my builder was pretty confident the solution they gave him on the phone would work. I'll try to get him to tell me what it was when I pick up the engine. Cometic is replacing the gaskets at least."

"Vid as promised: http://www.100mphclub.com/movies/331_idle.mov 6.7MB

Car wasn't warmed up enough to idle in park, but did in gear. Figures. LOL I even snuck a vid of the defective gaskets in there. Water and oil coming out everywhere from both heads. This particular shot was the easiest to get on camera."

The end result was that Cometic sent us new gaskets, said they were fully aware of the issue they had with Ford heads and were working on a sealant solution. Something about coating the gaskets from their factory.

My builder covered the new set.... and so far no leaks. I'm pulling the engine out right now due to a failed oil pump.

It's winter, and we decided to check out the gaskets again while we are inspecting the internals. PLUS, we're going to clearance the pistons a hair so I can change to a thinner gasket (ie switch brands, if I want to). I'll let everyone know how the gaskets look when I get that far.

But yes, I would call Cometic. The least they can do is send you a new set of gaskets. If you decide you want to go a different route, then sell the new ones or keep them for a spare.

 

[BYRDPE]

That shaft looks just like the one I pulled from my engine about a week ago.
After removing the pump I opened it up and found a peice of old gasket material.
I'm sure it got in there during my H/C/I install.

 

[gcomfx.com]

That shaft looks just like the one I pulled from my engine about a week ago.
After removing the pump I opened it up and found a peice of old gasket material.
I'm sure it got in there during my H/C/I install.

How did it get past the screen? I don't know what to expect on mine. The oil pressure jumped around for about 40 miles until I got to the track. As I crossed the road into the track, it seized up and broke the shaft.

I drove to the dragstrip.... then had to be trailered in.

 

[soontobefastfox]

gcomfx.com,

Wow your leak is much more serve than mine! I've contacted Fel-Pro and they said their MLS gaskets are sealed unlike the cometic MLS. I would rather go with Fel Pro because I have used their gaskets for everything and never had them leak. Maybe I can get Cometic to give me a refund, or just send me new gaskets and sell them. Looks like I have to tear down the engine this winter, not a big deal just a PITA after spending money and so called "high performance" parts.

 

[gcomfx.com]

If I find that sealant locked up my oil pump, I'll REALLY be pissed off.

This was my project last winter. I made it to the track ONCE the entire year.

Next has to be better. LOL - the rear end is upgraded now, so I shouldn't bend any more axles at least. Good luck.... as I stated. Cometic was the only one that made a gasket thick enough. We're about to solve that problem. We need to change the rings anyway. I was getting blow by with them setup for nitrous.

Too bad it's right before Christmas. I'm going to try to get an aftermarket oil pan too.

 

[soontobefastfox]

If I find that sealant locked up my oil pump, I'll REALLY be pissed off.

This was my project last winter. I made it to the track ONCE the entire year.

Next has to be better. LOL - the rear end is upgraded now, so I shouldn't bend any more axles at least. Good luck.... as I stated. Cometic was the only one that made a gasket thick enough. We're about to solve that problem. We need to change the rings anyway. I was getting blow by with them setup for nitrous.

Too bad it's right before Christmas. I'm going to try to get an aftermarket oil pan too.

I hear you man. I am a college student (got a scholarship) and I work as a engineering co-op (Kettering, old GMI, 3 months co-op/3 months school) and I saved for so long (purchased the stang when I was 15 and paid it off in one summer, 3 jobs) and spent 2 years building my stang. I got to drive my mustang 100 miles, once I found there was like no pressure in the cooling system and she was running hot it got me worried. I lost a whole summer of driving, but live and learn I guess.

I just called Cometic and what a load of **** that was. They need me to send them the gaskets to look at them. But they most likely will not send me a refund because the gaskets are older than 30 business days (WTF?!?). I bought them about a year ago when I started to build the engine. The tech I spoke tried to deny there are problems with these gaskets.

All I want is my 160 dollars back to purchase Fel Pro MLS.

I'm glad I got one stang to drive around atleast. I love my 07, but it doesn't have the balls out crazy power as my 88.

Good luck on your rebuild and keep my posted.

 

[gcomfx.com]

Send the cometic people here. My engine builder will chime in as well. LOL

 

[Rick 91GT]

Here's the only solution I have found with the Cometic gaskets...

Go to your local Chrysler dealer and get a can of their gasket spray, the can in black with a white top. Spray both sides of the gasket, letting them tack up and then install them on the motor. I learned this from a Outlaw racer that had issue with the cometics, they actually tend to leak between the layers. I now build with the Fle-Pro MLS which come with a slightly tacky coating on them and I have not had a sealing issue yet.

They say not to spray them but the above coating has been very successful in my engines with 600-900HP and lots of cylinder pressure IE: N2O, Superchargers, etc...

 

[BYRDPE]

How did it get past the screen? I don't know what to expect on mine. The oil pressure jumped around for about 40 miles until I got to the track. As I crossed the road into the track, it seized up and broke the shaft.

I drove to the dragstrip.... then had to be trailered in.

Man I have no idea how it got through. I thought I was really careful stuffing all open holes prior to scraping the old gasket material.
I ran my new combo for about a week before the shaft broke.
I put a new HV melling w/HD shaft and I see 50 psi consistantly.

 

[black87ttop]

How did it get past the screen? I don't know what to expect on mine. The oil pressure jumped around for about 40 miles until I got to the track. As I crossed the road into the track, it seized up and broke the shaft.

I drove to the dragstrip.... then had to be trailered in.

just curious as to if the times in your sig are for the stroker or if they were old from a 302, i would think you should see better times than that
.
IM building a 347 for my 87 right now and im hoping for 11's on motor.

 

[bluevenom867]

Here's the only solution I have found with the Cometic gaskets...

Go to your local Chrysler dealer and get a can of their gasket spray, the can in black with a white top. Spray both sides of the gasket, letting them tack up and then install them on the motor. I learned this from a Outlaw racer that had issue with the cometics, they actually tend to leak between the layers. I now build with the Fle-Pro MLS which come with a slightly tacky coating on them and I have not had a sealing issue yet.

They say not to spray them but the above coating has been very successful in my engines with 600-900HP and lots of cylinder pressure IE: N2O, Superchargers, etc...

Yea,I've heard they can leak between layers. I've never experianced a problem,but I have only delt with them on 351W engines (1/2" studs with 110-125ft.-lbs. torque).

Ill tell you one gasket Im very happy with is the SCE TITAN ICS gasket Im runing now.

But all these new gaskets just make it easy,if you got the time nothing better than a good solid copper gasket with an o-ringed block.

 

[gcomfx.com]

just curious as to if the times in your sig are for the stroker or if they were old from a 302, i would think you should see better times than that
.
IM building a 347 for my 87 right now and im hoping for 11's on motor.

I don't want to make excuses, but it hasn't really had a fair shakedown yet. It was the only trip to the track in the car this year. It was 102 degrees that day, and it's a temp tune on the car with near stock suspension. Wideband showed the engine was at 10.8 at WOT. I hit it with the 75 shot still on the N/A setting. The A/F moved to 11.0 It was our local car club challenge and I wanted to run the car, open loop or not. Don leaned the tune out since, but I keep breaking various things along the way.

Here's a video after the break in - first tune which was a bit leaner but had a lot more power. http://www.100mphclub.com/movies/331_gcomfx2.mov

The trip when the oil pump gave up. I had changed the rear to 31 spline 04 cobra carrier, moser axles, added sub-frame connectors, upper and lower control arms, 17" ET Streets, switched from 3.73s to 3.55s, and had a much better tune... not to mention two bottles of nitrous and rejetted back to the 125 shot. I was ready for some better numbers. I think I scared the oil pump to death on the way.

 

[gcomfx.com]

I guess I should also point out, that my original goal with this engine was to run N/A what I did on the 125 shot before. I squeaked past that my first trip. Best before was a 12.79 @ 108. The engine just about made it to 200,000 miles. I sprayed it for 6.5 years.

Also my turd started as a 15.9 car. It's a street car, that I occasionally have to take on long trips for work. 4-5 hour drives one way. It also has 9.89:1 compression - a super charger was in the original plan. My budget is all blown to heck now though.

 

[Mike92GT]

I have Cometics on my car and I've had zero problems thus far. I'm actually on my second set because I didn't want to try and re-use them when I replaced my short block. Did you used head bolts or studs? I used ARP studs with mine, as I wanted to get the best seal possible for use with my blower. Also Cometic recommends a very smooth deck surface. I used a sanding block and some 400 and 600 grit wet-sand paper to smooth out my deck and heads before assembly.

 

[PUNISHER RACING]

Felpro 1011-2 head gaskets they get it done on blower cars

 

[soontobefastfox]

I have Cometics on my car and I've had zero problems thus far. I'm actually on my second set because I didn't want to try and re-use them when I replaced my short block. Did you used head bolts or studs? I used ARP studs with mine, as I wanted to get the best seal possible for use with my blower. Also Cometic recommends a very smooth deck surface. I used a sanding block and some 400 and 600 grit wet-sand paper to smooth out my deck and heads before assembly.

I used ARP bolts with mine (I intended to go with studs, but I am running victor jr heads, and they have 1/2" openings, while my block has 7/16). I have a sportsman 302 block and I had it decked and the head surface looked at.

 

[Mike92GT]

You can still use studs with your heads if you decide to switch over. My Eddys also have the 1/2 head bolt holes. You just need the step washers / inserts that fit inside the holes in the cylinder head. I don't think it has been mentioned, but did you use thread sealant on the short head bolts?

I used ARP bolts with mine (I intended to go with studs, but I am running victor jr heads, and they have 1/2" openings, while my block has 7/16). I have a sportsman 302 block and I had it decked and the head surface looked at.