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Alternator Mounting Bracket Cracked

SEGA

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Good Morning Everyone,

I was changing the oil in my 6A and wiping off grime and found a through-and-through crack on the cast aluminum mounting bracket for the alternator (see pics). I was wondering if anyone knew where to purchase a replacement off the shelf or the torque spec for the mounting bolts to the engine case and alternator pin. The alternator is on the starboard side of the case, and the engine is an ECi XIO-360. Thank you so much for the help!

-SEGA
 

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From looking at the first picture....it appears there could be a side loading of the mounting bracket, which would explain the crack. Some brackets in that position are u shaped with a long through bolt, called boss mounts, so the load spread across the bracket. I can't tell from the picture what the rear tab is actually.
Clearly you can replace the existing bracket, but prudence would have you looking into WHY it cracked.
 
Also, looks like the strap that ties the starter to the alternator bracket to stabilize side loads is missing in this installation.
 
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Also, looks like the strap that ties the starter to the alternator bracket to stabilize side loads is missing in this installation.

Good catch. That support strap is a 3/16" steel strap who's primary purpose in life is to avoid the side load on the Alt pivot bolt. That Alt bracket is not designed to take that side load; it is counting on the strap to do that. Not a design flaw, but an installation error. You can see the side load stress based upon the crack orientation. Directly parallel to the load carried by the missing support strap. The empty threaded hole on the starter IS NOT an extra; it is for the other end of the strap.

Larry
 
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Vans sells a U shaped bracket that should work, and like Ralph said, I agree that the tie strap is critical. I had to make my own, but not a big deal.
 

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Those old aluminum/extruded/welded brackets are junk and would break all the time. The brackets currently supplied with B&C/Planepower are heavy steel and never fail, the starter/alt support bracket is no longer required with these new brackets and lightweight components. Might be time to upgrade.
 
Safety wire

You may also want to change the bolts that attach the unit to the engine to drilled head so they may be safety wired to each other.
 
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