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My portable generator ran fine for 5 hours, then ran out of gas. I refilled the tank but now the pull is excessively hard and the unit will not start. I removed the spark plug and the pull was normal.

What next?

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Please describe more about after the spark plug was pulled out. For example, it should be really easy with it out, easier than when in place before the trouble started. Then you put it back in and pulled it was normal? or is it excessively hard again when it is replaced? – Jack Dec 10 '13 at 19:38
You have enough oil in the engine? It could something screwed up in the crankshaft. In other words it sounds related to the engine and it doesn't sound like a problem with the pull. – maple_shaft Dec 10 '13 at 20:22
Check the intake and exhaust for any restrictions. 2 stroke Engines are fairly simple, air/fuel mix in, exhaust out. Check for sticking valves, or blockages. Including the make and model number of the generator might be useful. – Tester101 Dec 13 '13 at 12:03
Mine is the same but I was using 95 octane fuel should have used 91. may have over heated??/ Just guessing – NLJ May 22 at 12:51

Mine is doing the same. I fully disassembled after checking the easy stuff. The decompression lobe on the cam is no longer functioning. Mine needs a cam.

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Could have been a compression problem which got worse because there was no ignition. That's why some chainsaws have a push button on the cylinder-head to relieve pressure in the cylinder, which makes it that much easier to start them. (otherwise with each pull the compression gets worse and therefore the pulling gets a lot more difficult)

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That would not be it. Engines do not accumulate compression with each pull. Any built up compression from failed ignition is released at the end of the cycle. The decompression valves you refer to act to reduce the compression level of each cycle during the starting procedure, it does not relieve built up pressure from previous cycles. – bcworkz Dec 11 '13 at 23:03
It obviously has something to do with compression, as it's only hard to pull when there is compression. – Mazura Feb 24 at 5:28

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