394 cylinder/piston damage due to throttle plate sucked in.....is it salvageable?

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aquan8tor

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So a while back I had a bad day with my 394XP; it was always a hard starter, 5-7 pulls cold at least, sometimes 10. This particular day it ran great, until I heard a little pinging sound like a screw or something hitting the inside of the cylinder walls. Well, that was exactly what I heard. The carb throttle plate (or choke plate got sucked through. I don't know which; it happened a while back and I tore it down right away. Turns out that the screw holding it on had corroded right through; (I know this because I noticed it when I did a carb rebuild a few months before it happened, shame on me for not replacing it then....). I had put loctite on the screw, but I guess that wasn't enough; I noticed rust where it screwed down. Explanation aside, here's the pics. What I want to know is, is it worth getting a new piston (and coil, because now it has no spark after sitting, and I checked the switch) to try and fix it, or is the damage to the ports going to completely screw up the timing because of the chips in the cylinder? They're small, but I know only a few mm can be a big deal. There's no scoring, and this is an expensive cylinder to replace. I have a spare carb; the plate from the other one is trash after going through the crankcase. I got a bunch of little tiny pieces of steel out too from the screw; it looks like it shattered when it got sucked in.

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Last edited:
I was worried about further screwing up the intake timing. The piston replacement is a sure thing. The rings are frozen, and compression was LOOOOOOOOW after this event. I didn't test it, but lets just say there was no difference between using the decomp button and not using it.
 
A new aftermarket piston will come with rings so you will be all set there.
blend carefull the dings in the port as said and dont worry.
 

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