Coolant leek with copper gaskets
Thread Starter
Burning Brakes
Joined: Oct 2000
Posts: 792
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From: Palatine
Coolant leek with copper gaskets
Bolted on some new aluminum trick flow heads to a stock 350 block. Getting a bit of coolant leek from the drivers side. Doesnt look like im getting any in the cylinder as the exhaust seems pretty clean. Should I just try retorquing or pull the head and try a non copper gasket?
Melting Slicks
Joined: Jan 2004
Posts: 2,527
Likes: 1
From: St. Petersburg, Fl///Columbus, Ohio
Bolted on some new aluminum trick flow heads to a stock 350 block. Getting a bit of coolant leek from the drivers side. Doesnt look like im getting any in the cylinder as the exhaust seems pretty clean. Should I just try retorquing or pull the head and try a non copper gasket?
What type of head gaskets are you using??? re-torquing one bolt at a time might help
Last edited by jcswm; Aug 23, 2007 at 07:43 PM.
Pro
Joined: Apr 2006
Posts: 625
Likes: 49
From: Southern California
Bolted on some new aluminum trick flow heads to a stock 350 block. Getting a bit of coolant leek from the drivers side. Doesnt look like im getting any in the cylinder as the exhaust seems pretty clean. Should I just try retorquing or pull the head and try a non copper gasket?
Racer
Joined: Apr 2004
Posts: 401
Likes: 0
From: IL
Blue RTV is not the best even though it says it's rated for coolant and oil. If all the bolts are torqued properly and a better RTV is used there should be no issues. If the silicone is "washed away", retorque is not going to help. Does it leak only at certain times or temps, such as warm ups?
I prefer gaskets with an embossed bead instead of just a flat sheet. These conform to surfaces and adapt to different temperature changes and the changing expansion rates of multi-metal (cast iron, aluminum,etc) engines. For the money you spent on those you could have gotten MLS stainless steel viton coated gaskets for for your application. Though the hiperf composites would have been fine. Cooper are better for re-usability, such as teardowns between rounds or races, but not typically ideal for street. Though depending on application we've been able to reuse the MLS's over again. But don't let them know I told you, that's like taken food off my kid's table when you don't have to buy more.
Do not spray or coat the composites or coated gaskets as they have been engineered to seal yet let the parts expand and "slide around" at different rates.
I prefer gaskets with an embossed bead instead of just a flat sheet. These conform to surfaces and adapt to different temperature changes and the changing expansion rates of multi-metal (cast iron, aluminum,etc) engines. For the money you spent on those you could have gotten MLS stainless steel viton coated gaskets for for your application. Though the hiperf composites would have been fine. Cooper are better for re-usability, such as teardowns between rounds or races, but not typically ideal for street. Though depending on application we've been able to reuse the MLS's over again. But don't let them know I told you, that's like taken food off my kid's table when you don't have to buy more.
Do not spray or coat the composites or coated gaskets as they have been engineered to seal yet let the parts expand and "slide around" at different rates.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
Copper is only truly worth the trouble for hardcore engines. I never ran them without O-ringing, but if you insist - Indian Head Shellac...
Should you change head gaskets, make sure and do the math on piston to head clearance. You're looking for about 0.040 - 0.050", ideally.
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Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
Long ago I ran copper head gaskets on a blower motor in a boat. The heads were o-ringed, so as long as water didn't get into the cylinders, I didn't care if they leaked.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Copper is only truly worth the trouble for hardcore engines. I never ran them without O-ringing, but if you insist - Indian Head Shellac...
Should you change head gaskets, make sure and do the math on piston to head clearance. You're looking for about 0.040 - 0.050", ideally.
Copper is only for race motors that get frequent tear downs. I use Flatout silicone/rubber coated copper head gaskets because I needed .021 thickness to get my quench down to .041. But I also have a aftermarket engine block where all the head studs go into blind holes. That is the where the block casting is made so no water or oil is open to the bolt or stud.
I use fully studded motors to keep the heads correct. But one overheat and copper head gaskets can start to leak. You are better off using FelPro for Aluminum heads
Without perfect surfaces the copper can not seal. That where O-ring blocks help.
