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spark plug cap and carb coming off? any one else

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on both my yamaha 4 strokes, i have had problems with the spark plug cap, coming up of the spark plug a little bit, but you can tell that it off, becasue there is a sharp loss of power, also i have heard, that the carb can slip off the intake in a tip over has that happend to any one else?

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My carb is getting a bit loose on the intake port, I can twist the carb with the clamp fully tightened. I'm going to cut a bit off the clamp spacer so it tightens a bit more.

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the guy that i heard about this happening to he took 2 zip-ty's and wraped it around carb.starting at the motor mounts, going down in between the choke and the fuel intake hose, then it goes down to the folt bowl, and then hooks the ziptys together. pretty trick!

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I read here almost every day and this is the first complaint I remember seeing about carb and spark plug cap coming loose.

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The spark plug cap can do this if the drain port coming from the plug well gets clogged. This is particularly true if there's any moisture in the well. Run a piece of wire in through the hole on the right side of the cylinder head far enough to reach to the spark plug to make sure it's clear use compressed air if available.

If the carb is loose in the rubber isolator with the clamps tight, replace the isolator. It has shrunk. The clamps contain a captive distance sleeve that limits how far they can compress the rubber. This is done so that the screws can be tightened down solidly to keep them tight and still not crush the rubber too much. I don't recommend modifying them.

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If the carb is loose in the rubber isolator with the clamps tight, replace the isolator. It has shrunk. The clamps contain a captive distance sleeve that limits how far they can compress the rubber. This is done so that the screws can be tightened down solidly to keep them tight and still not crush the rubber too much. I don't recommend modifying them.

Too late. :)

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