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Discussion Starter · #1 ·
I replaced my front head because of a valve issue and of course used a new head gasket. I torqued the bolts as required by the manual; tighten each time in noted pattern first to 25.8 ft-lb, then loosen each 1 full turn, then tighten each to 14.8 ft-lb and tighten a further 90 degrees, then install smaller 3 bolts to 86 in-lb. After reassembly, the coolant is leaking into the exhaust. Has anyone experienced this and any recommendation to solve? I do NOT want to pull the engine again after getting it re-installed.
 

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I replaced my front head because of a valve issue and of course used a new head gasket. I torqued the bolts as required by the manual; tighten each time in noted pattern first to 25.8 ft-lb, then loosen each 1 full turn, then tighten each to 14.8 ft-lb and tighten a further 90 degrees, then install smaller 3 bolts to 86 in-lb. After reassembly, the coolant is leaking into the exhaust. Has anyone experienced this and any recommendation to solve? I do NOT want to pull the engine again after getting it re-installed.
New or used head? Sounds like it's cracked between the port and coolant cavity. No other explanation. If you make a small plate with a rubber gasket and air fitting you can confirm. Have the exhaust valves closed and the coolant filler cap off. Lower the fluid level some. Use about 15-20 psi regulated air and see if bubbling can be heard at the coolant filler or it's actually forcing fluid out. If so, I see no option but pull the head and check the gasket carefully and for any cracks in the head. The air test can also be done with the head off to pin point the crack if there is one.
Ron
 

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Discussion Starter · #3 ·
Thanks for the reply. This is a brand new head and a brand new head gasket. Everything on the engine block looked amazingly clean. I'm convinced its a leak at the gasket. Some coolant comes out by the exhaust outlet and some goes through the exhaust. I just can't figure out why, or what I need to do different.
 

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Thanks for the reply. This is a brand new head and a brand new head gasket. Everything on the engine block looked amazingly clean. I'm convinced its a leak at the gasket. Some coolant comes out by the exhaust outlet and some goes through the exhaust. I just can't figure out why, or what I need to do different.
You can test the head gasket with a made up air fitting in place of the spark plug. I just use an old spark plug, break out the ceramics, weld to a pipe and weld the air line fitting to the end of it. You will need to lock up the engine when it's at top dead center compression on that cyl or it will try to rotate. I suggest just a hair past top dead center so any unwanted rotation will remain in the correct direction. Place it in top gear and park the front wheel against the wall. At 50psi it should hold there. Best to run main line pressure if possible and throwing a wrench on the stator bolt with a helper is a better method. If the head gasket is leaking, two things will happen. It will show an external leak or into the exhaust port or you will hear bubbling in the coolant fill cap area. It might be hard to isolate between a gasket or crack but with the exhaust valve closed, it will tend to point more in the direction of the head gasket itself. The exhaust port pressure test will lean more toward a head problem rather then the head gasket.
Ron
 
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