Question about Harley Davidson FLHR - FLHRCI Road king Motorcycles

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The small hole behind the petcock is leaking gas is the diaphram bad or is it pressure problem from maybe the gas cap

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It's a diaphragm problem most likely. These things are notorious for giving problems. I always suggest people upgrade to a high quality manually operated petcock like a Pingle.

But, if you want to keep you vacuum operated petcock, you'll have to drain the tank of fuel. Get a large funnel and an empty gasoline can. Loosen the petcock with the large funnel to catch the fuel and guide it into the empty can. Unplug the fuel line and the vacuum line. Remove the petcock from the tank.

On the backside of the petcock, there's four small screws. Remove the screws and carefully take the back off the petcock. There's diaphragm, a needle and a small spring behind the plate. Hold the diaphragm up to the light and gently stretch it. Look for holes. You can get a replacement diaphragm from your local dealer.

Good Luck

Posted on Sep 10, 2010


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