Coolant leak

[5str48]

Recently replaced the head on 85 gl1200, but re-used head gasket which had been torqued down but not subject to the engine having been run.(Still looked new) Coolant is now running down exhaust port even when engine is off. I'm guessing that re-using the head gasket was my mistake. Engine was started and run briefly. Thoughts?

[Maz]

Head gaskets should never be re-used. It will have lost its ability to compress and seal the joint.
Maz

[roadwanderer2]

Head Gaskets are a necessary replacement item whenever you remove an engine head be it on a car, truck, motorcycle or any other gas or diesel powered engine. If you want to make sure you got it fixed, DO BOTH SIDES, and torque the heads down per your repair manual. You'll save yourself a lot of headaches in the long run.

Stuart, a.k.a.roadwanderer2.

[CrystalPistol]

No matter now, that head will have to come off again. Time to put in a NEW unused head gasket this time. Look close, make sure no signs of a crack or surface gouges.

I have a habit I acquired since replacing head gaskets on my '69 340 Swinger, it had 4 cylinders that had 4 head bolts while the other 4 had 5 head bolts. After a second occurrence, parts man at local Mopar shop told me to spray new ones with a couple coats Rubber-Seal High Heat Aluminum spray paint & let dry, then apply & torque. I still do it that way near 50 years later, but now it's often Krylon or RustOleum brand. Never had another one fail. I've used it on steel shim, composition, and copper sheet head gaskets. After install, one heat cycle, it's done.

[5str48]

No matter now, that head will have to come off again. Time to put in a NEW unused head gasket this time. Look close, make sure no signs of a crack or surface gouges.

I have a habit I acquired since replacing head gaskets on my '69 340 Swinger, it had 4 cylinders that had 4 head bolts while the other 4 had 5 head bolts. After a second occurrence, parts man at local Mopar shop told me to spray new ones with a couple coats Rubber-Seal High Heat Aluminum spray paint & let dry, then apply & torque. I still do it that way near 50 years later, but now it's often Krylon or RustOleum brand. Never had another one fail. I've used it on steel shim, composition, and copper sheet head gaskets. After install, one heat cycle, it's done.

Never heard of this. Manual says not to use any foreign matter on new head gasket. Are you absolutely sure of this? Can you name a specific current brand you use?

[CrystalPistol]

Never heard of this. Manual says not to use any foreign matter on new head gasket. Are you absolutely sure of this? Can you name a specific current brand you use?

I know.

YES,

I've used it on my Norton Commando, my Triumph Tridents, my 454 Chevelle, my '69 Dart Swinger 340, my '65 GTO, my Wheel Horse, my '77 F150, and others over the years since early '70s. As long as it's a HIGH HEAT ALUMINUM ENGINE PAINT, it'll have a lot of powdered aluminum in it for color & body. Not simply silver, black, red, blue, gold … just ALUMINUM. My first uses were Rubber Seal, but since then, I've used Krylon, RustOleum, even Tractor Supply. I've used this method on every head gasket R&R since. That first use was after blowing head gaskets on that high compression '69 340, it always blew on the top side of one of the 4 cylinders that only have 4 head bolts around them.

You do what you want as I make no warranty, but I'll always use it.

Google "aluminum paint on head gaskets".