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Old 10-13-2013, 07:34 PM
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Jeff in Pa Jeff in Pa is offline
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Join Date: Feb 2012
Location: Zionsville, PA
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Quote:
Originally Posted by finsruskw View Post
My experience w/this is that by the time you get the busted one out (drilled or driven), the hole is hogged out so much a new press zerk won't stay in. And if you drill and tap, the new one will be screwed in so far by the time it gets tight it will be sticking ithrough into the shaft hole and you will have to file the inside down for clearance. At least that's the way it worked out for me on a wide frame spindle.

Dave S
Perhaps you ran the tap in too far. In most cases, the NPT tap is turned in 2/3 rds of the body height for "correct" pitch diameter. Some blueprints for cast iron NPT holes call for them to be tapped shallow to allow for wear. In those cases we run the tap in about 1/2 way which is about 2-3 turns on the gage too shallow.

You can grind the bottom of the fittin goff too if it protrudes into the mounting bore.
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