High compression head coolant leaking

We'll I have got nothing but problems. I retorqued I'm the morning then drive around town for about 9 miles. "Highlight of my day, had a nice cruise". Well when I got home I noticed coolant still seeping through the head but even worse my new aluminum radiator cracked along the bottom weld for the mounting tab. So I pulled the radiator to find someone to reweld n repair it. Then I pulled the new head, going to have it checked for flatness. I'm thinking of ordering the copper gasket and give it a try.
Now with the copper gasket is it a copper rtv or a copper tack spray I should get?
 
Ok, I went with the copper gasket and a ton of permatex copper spray. It's had coolant in it for about 4 hours and so far no leaks. I'm going to give it until tomorrow to sit. I torqued the high compression head to 55 ft pounds following the correct tightening sequence. I torqued 20lbs, 35lbs then 55lbs.
Should I try to leave it at 55ft lbs. or go to 65ft lbs? And should I warm the engine tomorrow then retorque while it's still hot, warm or wait until it's cool again? I hope this will be my last time with this head and want to do it right. What works for you guys? Thanks.
 
An old trick in the book I do is get some aluminum spray paint and give the head gaskets a few coats. When the head heats up the paint will fill in most imperfection. My gamps has been doing it for years and swears by it.
 
I torque up in steps like you said, then retorque it hot, then run it for a while and retorque it again. This always seems to work for me.
 
Ok, I was going to let it warm up then retorque. I usually get a good 1/4 to 1/2 turn more out of it when it's hot. Then retorque it a few other times afterwards. Cold and hot. We'll see tomorrow how it holds up.
I did take all the head bolts out last time and clean all the studs free of any left over rtv. I then hit head and block surface lightly with a piece of scotch pad then wiped down with 99.9% alcohol to make sure surfaces were completely clean. I also rechecked head and block with the side of a 12in machinist ruler to check for flatness. No stud holes were raised or anything.
 
My bad I did not see that post where he said he used the copper coat. Besides that you are right on re-torquing when hot its better when everything has expanded.
 
tbirdtbird said:
Not RTV. It can clog things up.
Copper tack spray such as Permatex #80697; be generous with it.

There is a product K&W copper sealer. It comes in a dauber can. I used it once and then threw it away because right after I installed the head, like the next day, we had to remove it for some stupid reason, and we could hardly get it off, the K&W had a glue-like quality to it, and destroyed the gasket getting the head off. But you could prolly seal up a leak the size of Ohio with it.
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tbirdtbird, K&W sealer also comes in a spray and works just like the coppercoat and won't stick the head so tight as the liquid with the dauber.
 
captain j said:
Ok, I went with the copper gasket and a ton of permatex copper spray. It's had coolant in it for about 4 hours and so far no leaks. I'm going to give it until tomorrow to sit. I torqued the high compression head to 55 ft pounds following the correct tightening sequence. I torqued 20lbs, 35lbs then 55lbs.
Should I try to leave it at 55ft lbs. or go to 65ft lbs? And should I warm the engine tomorrow then retorque while it's still hot, warm or wait until it's cool again? I hope this will be my last time with this head and want to do it right. What works for you guys? Thanks.
Click to expand...
Sounds like you have the problem well in hand. I would only torque the head when it is cold. My reason for this is, when you heat the motor the cast expands and compresses the gasket. If you retorque it hot the metal is still expanded and will give a false sense of security because, when the metal cools and contracts, the torque will change. Try torqueing the head 3 or 4 times when it cools till the nuts no longer move at the specific torque setting. I always go to 55 and have good success. My personal use, I have not had a failure since I started doing my head installs this way.
 
At least, the first retorque needs to be done when hot. I don't expect my first retorque to hold 55 ft. lbs. I do the first retorque to prevent water from entering the crankcase. You lose so much torque on the head nuts after the first 20 minutes that there is a risk of coolant entering the crankcase. The head can be retorqued as many times as needed after the engine cools . I've had good results by first retorqueing when hot .After the first retorque , I do all other retorqueings cold. With grade 5 studs, it may need five or six retorqueings. I would only use water until the studs hold 55 ft .lbs. torque. I only use water unless there is danger of freezing and then I drain.
 
I'm amazed that whether to torque and retorque hot or cold isn't settled science, or at least recognized best practice.

At this point, I don't know what to believe. I might add that Larry Brumfield was adamant about retorquing cold.
 
steve s said:
I'm amazed that whether to torque and retorque hot or cold isn't settled science, or at least recognized best practice.

At this point, I don't know what to believe. I might add that Larry Brumfield was adamant about retorquing cold.
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I'm not saying it isn't so but ... The way that I remember it was that brumfield wanted the first re torque to be performed at operating temperature. After the first retorque all other torques would be performed cold. That is the way that I did mine.
 
Well after the new copper gasket and the copper coat spray it seems ok. I warmed up the engine at idle let cool and retorqued. Then today I drove about 5 miles and still see no coolant leaking. Ill retorque tomorrow after it's cooled down. I'll leave the high compression head at 55ft lbs and just torque when it's cooled down unless I need to do it when it's warm.
 
I'm going through this now, it started off as a little and then today we torqued it again today and it still leaked but more.

Complete rebuild with the recommended gasket from Snyder on their 6.1 head. Engine was decked etc ... Frustrating to say the least
 
I use "Indian Head" shellac to coat all the insides of the stud hole and water passages in the head gaskets. Never had much gasket edge seep.

JB
 
Mr Brumfeld just posted over on Ahooga about how to properly re-torque a head gasket properly: COLD.
If I remember correctly that's also the way Henry said to do it. FWIW

Paul in CT

Copper gasket and copper spray is probably the best way to go. When the "new" gasket came out there were many people posting about problems with them. Not so with the copper gasket. also FWIW
 
I have re-torqued both hot and cold. Never had a head leak. My racing Velocettes and Nortons (old style British motorbikes) never even had head gaskets although I ran them at about 15:1 compression. It was all in the preparation of the mating surfaces. Anyone else ever use a scraper and engineer's blue?

Just my round about way of saying that if the head and deck are really flat and true, then the rest is easy.

Check the deck and head using engineer's blue (cannot remember N. American name) and a surface plate which can be a piece of plate glass. Sorry guys, but using a straight edge is a rough approximation and not good enough.
 
I don't want to get in on the hot/ cold re-torque issue but I have a issue with my torque wrench instructions. It states never re -tighten a nut unless you back it off and then bring it back to your torque specs. I have never done this. I just re-torque the nuts several time until I get no more movement and they hold at 55 lbs. My torque wrench is a Chraftsman and I have checked instructions of other makes of wrenches and the instructions are the same. They all say never re-tighten a nut with out backing it off first. WHAT YOU YOU GUYS THINK ABOUT THIS ?
 
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