Anyone have coolant leak with Cometic prior to startup, and then no leak?
#1
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Completed the engine assembly, filled with fluids, use a vacuum device to suck in the coolant, noticed a couple of drops coming out of gasket to head on driver side. After running the car for 30 minutes to heat cycle the valvesprings, the leak apparently stopped. I hosed everything down, and put a fan on it overnite, and will check again tomorrow to see if it is still leaking. Does this sometimes happen?
382 stroker, AFR 225 heads, Cometic gaskets. All prepped well, very clean, used Hylomar on ARP bolts/washers, etc. Nothing used on gaskets.
SDB
382 stroker, AFR 225 heads, Cometic gaskets. All prepped well, very clean, used Hylomar on ARP bolts/washers, etc. Nothing used on gaskets.
SDB
#2
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Cometics are very finicky, this I know.
Personally I've had nothing but issues with cometics, from subarus, to fords, to hondas. I haven't used them for GM and I probably won't. I am using SCE ICS gaskets this time around.
Anyway, some on here use the coolant pills and had success with cometics when they leak.
Personally I've had nothing but issues with cometics, from subarus, to fords, to hondas. I haven't used them for GM and I probably won't. I am using SCE ICS gaskets this time around.
Anyway, some on here use the coolant pills and had success with cometics when they leak.
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Originally Posted by SDB
Completed the engine assembly, filled with fluids, use a vacuum device to suck in the coolant, noticed a couple of drops coming out of gasket to head on driver side. After running the car for 30 minutes to heat cycle the valvesprings, the leak apparently stopped. I hosed everything down, and put a fan on it overnite, and will check again tomorrow to see if it is still leaking. Does this sometimes happen?
382 stroker, AFR 225 heads, Cometic gaskets. All prepped well, very clean, used Hylomar on ARP bolts/washers, etc. Nothing used on gaskets.
SDB
382 stroker, AFR 225 heads, Cometic gaskets. All prepped well, very clean, used Hylomar on ARP bolts/washers, etc. Nothing used on gaskets.
SDB
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There was a huge discussion on this a few weeks ago.. I'm sure you saw it. The guy had a 400+ci sleeved block that Darton machine and sleeved for him. He put it together and it was leaking slightly from the head gasket and he also used the Cometics. He ran the motor anyways and after a heat cycle it quit leaking. So he changed the oil and broke it in for a few hundred miles then put it on the dyno at Thunder Racing I believe. And the motor locked up on the dyno.. I think he was stuck with a shitty motor and it wasn't even his fault. The big discussion was about the sleeves and deck height of the sleeves. Steve @ RED said the sleeves were suppose to be flush with the deck of the block, but Darton East that did the work on the engine said that it would be fine with 5 thousanths of clearance over the deck. Obviously they were wrong..
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Originally Posted by ArcticZ28
Please tell me you didn't do a head upgrade on your wife's malibu ![Tongue](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_tongue.gif)
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Not yet...But, since I am pulling them off for the gasket swap, I don't see any harm in a little port matching..
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I am concerned now! I have a set of new .040" Cometics to go on my new shortblock, and never once heard of them leaking and stuff. Hell, I paid extra for them cause they were "re-usable" WTF?
#13
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never had a leak....period....and my gaskets have been on and off 10+ times......
it's all in how the deck/head surface is prepared.....do it right and you will never have problems.....do it wrong (or put a big scratch in the surface) and you will never get things sealed.....
it's all in how the deck/head surface is prepared.....do it right and you will never have problems.....do it wrong (or put a big scratch in the surface) and you will never get things sealed.....
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#14
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Originally Posted by 2001CamaroGuy
never had a leak....period....and my gaskets have been on and off 10+ times......
it's all in how the deck/head surface is prepared.....do it right and you will never have problems.....do it wrong (or put a big scratch in the surface) and you will never get things sealed.....
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
it's all in how the deck/head surface is prepared.....do it right and you will never have problems.....do it wrong (or put a big scratch in the surface) and you will never get things sealed.....
![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)