Join Date: Sep 2013
Location: Colorado Springs, Co
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Distributor Shaft End Play?
I fired up the 460 in the jetboat yesterday, and she was backfiring through the carb, running very rough. I checked timing, it was 40-60* at idle! She would die quickly if dropped to <30*.
Pulled the cap; it and the rotor are pretty chewed up, the rotor more-so than the cap. The rotor coil pickup tab is crushed into the rotor body. the end of the rotor arm is very chewed up. Obviously riding very high in the cap. The cap has some wear at the top of the contacts, the plastic has some shearing/wear.
This must have happened recently; I started it once a few months ago for 10-15sec, was getting it ready to finally get it in the water this year.
There is approx 1/8" vertical play in the distributor shaft, no perceptible side play. Dist is a Prestolite IBM-7025s (NOS a few years ago, limited hours on it) with a Pertronix 91582 Ignitor II conversion kit. Have several seasons with this converted dizzy and have had no problems.
Wondering how the rotor tab would get so crushed and how the rotor would contact the cap interior if the shaft is drawn downwards.
Also curious about the vertical end play. Is that something that is a precursor to major failure, or a normal amount of play?
1978 Glastron/Carlson CV23; 466ci/Berk
1997 Newmar Mountain Aire 3757; 460ci
1964 Falcon 'vert; 260ci, 351w 4v heads, C4, etc
2000 Big Dog Bulldog; 107" S&S, Shorty G, Bassani, etc
2004 Saab 95 Aero
1980 Bradley GTE