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Old 07-24-2007, 10:11 PM   #1
70heavyhalf
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Harmonic Balancer Rubbing Timing Cover

I noticed the Harmonic Balancer/pully on my 250 inline 6 was extremely close to the timing cover. Upon removal of the balancer, deep groves were cut in the cover, and one large crack. Any ideas as to why this would happen, except for someone installing it too close to the cover. Or maybe the thrust bearing is worn out and allowing the crank to walk a little.
Thanks
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Old 07-24-2007, 10:18 PM   #2
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Re: Harmonic Balancer Rubbing Timing Cover

Or the rubber on the damper allowed the outer ring to slip & make contact with the cover.
Got pictures?
s/t
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Old 07-24-2007, 11:10 PM   #3
70heavyhalf
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Re: Harmonic Balancer Rubbing Timing Cover

My dad and I took another look and we tried to move the crank from the rear of the engine and we are able to move the crank slightly with our hands so we think the thrust bearing is worn beyond spec.
Here are some pics.
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Old 07-24-2007, 11:17 PM   #4
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Re: Harmonic Balancer Rubbing Timing Cover

sorry forgot of pics.
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Old 07-24-2007, 11:21 PM   #5
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Re: Harmonic Balancer Rubbing Timing Cover

Here are a few more pics.
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Old 07-25-2007, 11:28 AM   #6
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Re: Harmonic Balancer Rubbing Timing Cover

Some one has to have an idea.
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Old 07-25-2007, 12:03 PM   #7
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Re: Harmonic Balancer Rubbing Timing Cover

Balancer only installs in one position. Check the balancer to see if the outer ring is on the same plane as the inner. Only two thing will cause this-thrust bearing or balancer.
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Old 07-25-2007, 12:23 PM   #8
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Re: Harmonic Balancer Rubbing Timing Cover

from the pic it looks like the crank is way to far back, check the thrust bearing.
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Old 07-25-2007, 02:36 PM   #9
70heavyhalf
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Re: Harmonic Balancer Rubbing Timing Cover

Thanks for all the help, it looks like the thurst bearing is worn because we are able to move the crank with our hands slightly. So the engine is going to need a rebuild so I guess its time to put the 350 in.
thanks again
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Old 07-25-2007, 09:00 PM   #10
PanelDeland
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Re: Harmonic Balancer Rubbing Timing Cover

If you can tell the crank is moving by hand then the thrust bearing is worn.Or you may have a bigger problem.
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