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Leaky heads

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Old Apr 25, 2023 | 09:32 AM
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Default Leaky heads

Has anyone out experience leaky heads at the spark plugs?
Im getting a leaky gas/ oil black looking stuff at the spark plugs, mostly the rear head.
Was told that aftermarket aluminum heads have done this because the boss landing where the spark plug rest isn’t flat. So took to machine shop and had it trued up, but yet still leaking.
Whats the fix?
 
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Old Apr 25, 2023 | 01:00 PM
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Do these heads have the cast in insert (bronze?) for the threads or are the threads cut directly into the aluminum ?
 
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Old Apr 25, 2023 | 01:12 PM
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Is it cracked? OEM heads like to crack at the spark plug hole.
 
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Old Apr 25, 2023 | 01:18 PM
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Old Apr 25, 2023 | 01:40 PM
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It appears that they have iron inserts, these are alum aftermarket heads and were also checked for cracks.
the problem is leaking around the spark plug area no where else.
 
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Old Apr 25, 2023 | 06:12 PM
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300 lb-ft I believe is the correct spark plug torque.....
 
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Old Apr 25, 2023 | 07:38 PM
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300lb on the plugs, you must own a rice rocket!
And use super glue instead of gaskets!!!
 
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Old Apr 26, 2023 | 06:55 AM
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Post pictures of what you're seeing, easier to help if we can see it.
 
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Old Apr 26, 2023 | 07:00 AM
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Probly ment 300 inch they use all metric in Iceland

indians do that a lot pulling the heads and replacing the inserts is one fix - but they leak around the out side of the insert and not the plug to insert thread

green loc tite on the out side thread is what we do and it seems to work - finding what thread will save you time put some never sneeze on the plug and take it for a ride 18mm plug thread if it is the plug a reducer to 14 mm and use a conventional plug instead of the big jamoke ones but that == once you green replacement is all u can do then going forward

 
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Old Apr 26, 2023 | 01:00 PM
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There was another posting like this a while back.
Turned out that the plug threads were at a slight angle to the sealing surface.
Quick trip to the machine shop solved the problem.
 
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