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Discussion Starter · #1 ·
My buddy broke a rocker arm in his motor. It has a weller 686 kit in it. Anyone know why it broke or have the same problem? Is there an upgraded rocker arm he can buy so it doesn't happen again?
 

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never heard of that,thats a new one..........check the witness pattern/imprints on the contact points and clearances,wonder if he ran it loose,or if the wingnut who built the engine didn't use shorter guides and ran a big cam and compressed the whole assembly busting the arm??????sounds funny,how does the inside of the exposed material look like? Is it poreous(full of casting holes)? Maybe a bad casting?...they are fordged steel so I'm currious to know what the inside of the rocker material looks like...strange...
 

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Have seen it before. Usually it's either the piston hit the valve and the valve breaks the rocker or an over-rev where the valves float and the rocker ends up getting impacted badly. Did it still run? Did you tear it down? The only upgrade we do to the rockers is having the faces hardwelded and that wont prevent rocker arms from breaking.

Nate
Alba Racing
 

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Discussion Starter · #4 ·
It started smoking and ran good for a few quick test rides around his house. Then he took it on a ride and it quit on him. He took it to the guy that put it together and he pulled the valve cover and found the broken rocker. I havnt seen it yet.
 

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It started smoking and ran good for a few quick test rides around his house. Then he took it on a ride and it quit on him. He took it to the guy that put it together and he pulled the valve cover and found the broken rocker. I havnt seen it yet.
Most likely the GUY didnt time the engine properly.............
 
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