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Old 08-14-2010, 07:07 AM   #11
gaillarry
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Re: Cross Threaded Spark Plug Hole

Going to pull the cylinder head and take it to a machine shop and have it done right. I have the manual, any tricks getting the head off?



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Old 08-14-2010, 08:13 AM   #12
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Re: Cross Threaded Spark Plug Hole

Just follow the manual, stuff a clean rag under the cam shaft gear so you dont drop any bolts into the crankcase. Also be sure to replace the cylinder base gasket.
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Old 08-22-2010, 08:05 AM   #13
gaillarry
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Re: Cross Threaded Spark Plug Hole

Got the head off and here's a pic of the piston top, lots of metal shavings and carbon buildup. New gaskets came in yesterday (base and headgasket) now to put it all back together. Local machine shop re-tapped the spark plug hole and the plug fits nicely.




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Old 08-22-2010, 03:44 PM   #14
Water Warrior 2
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Re: Cross Threaded Spark Plug Hole

Quote:
Originally Posted by gaillarry
Got the head off and here's a pic of the piston top, lots of metal shavings and carbon buildup. New gaskets came in yesterday (base and headgasket) now to put it all back together. Local machine shop re-tapped the spark plug hole and the plug fits nicely.

Looks like you are half way there.
Don't worry too much about carbon build up, it will increase the compression a tiny bit. :lol:
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Old 08-22-2010, 04:41 PM   #15
GTGZ
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Re: Cross Threaded Spark Plug Hole

Quote:
Don't worry too much about carbon build up, it will increase the compression a tiny bit. :lol:
Maybe .001%
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Old 08-22-2010, 04:51 PM   #16
gaillarry
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Re: Cross Threaded Spark Plug Hole

Since I had the carb off to remove the head I decided to clean it. The bike has been fouling spark plugs for years.

The cap was on the mixture screw from the factory. I drilled out the cap and to my shock the mixture screw was completely closed !!!! The tip of the screw is about 1/4" into the carb throat. Someone was asleep at the factory when the carb was assembled.

No wonder plugs were fouling and the piston was full of carbon. Whats the proper setting for the mixture screw!!
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Old 08-22-2010, 05:31 PM   #17
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Re: Cross Threaded Spark Plug Hole

About 2 1/2 turns out to start .Once you have engine started,adjust for smoothest idle,about half way between lean & rich.
:2tup: :rawk:
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Old 08-22-2010, 07:39 PM   #18
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Re: Cross Threaded Spark Plug Hole

Quote:
Originally Posted by gaillarry
No wonder plugs were fouling and the piston was full of carbon.
I think you may still have that problem.....because the screw being all the way IN would have made it more LEAN, not rich. If you have another problem actually making it rich, you may find that the idle mix screw has no effect.



P.S. Be **REALLY** careful not to overtighten the plug. You may be missing 1/3 of the original threads.......or more.
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Old 08-22-2010, 08:29 PM   #19
gaillarry
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Re: Cross Threaded Spark Plug Hole

I'll find out tomorrow when I start the bike. Have to let the gasket sealant on the valve cover set for the night. The machine shop did a good job of rethreading the spark plug hole, but advised me next time it'll need a helicoil.

I've read posts here - IN - Rich , OUT - lean...... or is it the other way around??
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Old 08-22-2010, 08:39 PM   #20
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Re: Cross Threaded Spark Plug Hole

Quote:
Originally Posted by gaillarry

I've read posts here - IN - Rich , OUT - lean...... or is it the other way around??
The other way around "In-lean,Out-rich". As EASY said with the mixture screw all the way in it would not be causing your rich mixture.But would definitely affect your idle.

:cool: :roll:
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