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1969 Johnson 6hp - Head bolt leaks

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FishyBC

Contributing Member
I had an earlier post about ignition on this motor and all is well now and it runs awesome but I did have to put the head back on this motor and now one of the cylinder head bolts leaks slightly. I replaced the head gasket and surfaced the head so it was smooth like described in other posts. I did unfortunately misunderstand the torque settings and over-torqued the head bolt. I have since torqued it to 7 inch lbs but it still leaks.

Would this have damaged the head gasket and be the cause of the leak ? If so I will order a new gasket and try again. I tried putting thread sealer on the bolt but that didn't make any difference. It's only weeps slightly but I'd like to fix it so I don't have to think about it.
 
racerone said:
Posting correct information is VERY important !
Click to expand...

Sorry Racerone ! Typo. I'll double check before posting in the future.

So if it's torqued correctly could it be the head gasket that is the reason that water is weeping through the head bolt ?
 
FishyBC said:
I had an earlier post about ignition on this motor and all is well now and it runs awesome but I did have to put the head back on this motor and now one of the cylinder head bolts leaks slightly. I replaced the head gasket and surfaced the head so it was smooth like described in other posts. I did unfortunately misunderstand the torque settings and over-torqued the head bolt. I have since torqued it to 7 inch lbs but it still leaks.

Would this have damaged the head gasket and be the cause of the leak ? If so I will order a new gasket and try again. I tried putting thread sealer on the bolt but that didn't make any difference. It's only weeps slightly but I'd like to fix it so I don't have to think about it.
Click to expand...

I figured I'd try one more time. Maybe this is a stupid question ?
Why would water leak past a head bolt and if it does, what is the best way to stop it ?
 
You said you surfaced the head. Are you sure you got the block perfectly clean? The head gasket has a thermo reactive (OEM gasket does) that will seal when engine reaches operating temp. You do have a thermostat in the motor? Re torque after the motor cools. If this doesn't stop the leak you can put a sealer on the gasket as a last resort. Permatex #30019 can be found at NAPA & other auto parts houses. Same procedure after application of sealer. Hope that does the trick!
 
I say just order a new head gasket and this time do it correct. Pull the head down slow in at least three steps using the proper torque pattern from the center out 60-80 inch lbs.
 
That works out to 7-9 NM IDK does that work out to 70-90 dNM? That also work out to 5-6.66 ft lbs. I just use a small 1/4 drive ratchet until my hand hurts evenly never had a issue. Knock on wood.
 
Perhaps the bolt hole goes all the way through to a water jacket. Remove the bolt and put some Permatex on it (the thick grade that comes in a squeeze tube).
 
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