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Diagnose my plugs?

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Diagnose my plugs?


Post by 51Hog » Sat May 17, 2008 12:50 am

How to these plugs look?
Left plug is the front.
I see some tiny round whitish BB looking things. They are soft and rub off easily.

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Post by FlatHeadSix » Sat May 17, 2008 1:55 pm

Those plugs actually look pretty good for 4K miles, the edges of the center electrode tips are sharp with no erosion or build up. The color difference is probably due to the age old argument about temperature differences between the front and rear cylinder. The front jug catches all the fresh cool air and probably runs a few degrees cooler than the rear. There has also been a lot of debate about whether the front cylinder runs a little leaner than the rear, just an accident of design.

The white deposits are most likely an oxide or hydroxide of whatever mystery additives they are blending into pump fuel these days. They are most likely harmless and temporary as you noted, they rub right off. They are also probably specific to whatever brand of fuel you are using and would change appearance or go away if you switched to another brand for a while.

clean 'em up and run 'em another 4K


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diagnose my plugs


Post by drinner-okc » Sat May 17, 2008 2:05 pm

and add just a tad of anti-sieze to the threads.

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Post by john HD » Sat May 17, 2008 3:22 pm

they look good to me, i got about 3 seasons out of my last set before i started tinkering with my linkert.


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Post by 51Hog » Sat May 17, 2008 3:56 pm

Thanks guys- I thought they looked good--I just had never seen the "BB" deposits. Unless they were aluminum from melting pistons.
I will get some anti seize.

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