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Posted

On my 2004 400ex I bought a magnum stage 2 cam and pulled the cam flang off the stock one also i put a 440 kit new timing chain. the problem I am having is I cant get it to run. I have timed it with the book spec I Know the 400 ex timing is tricky but I have redone it 4 times. i even advaced it like you would in a pick up truck. 2 teeth still just back firing. None out of the carb. please any advice???

Posted

What was the reason for the cam change? Any noises before the tear down? Maybe your timing mark is off. Verify that the piston is at TDC. Stick a screwdriver in the sparkplug hole and make sure the piston is at tdc then check the timing mark. That way you also know your crank is timed too. Then make sure you have spark, no air leaks blah blah

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Posted

The reason for the new cam cam was more power no misfuntion or noises just normal wear what originaly happen I demolished the piston rings jug. So I rebuilt it to a 440 so I figured why not put the stage 2 . I have done the tdc everytime I have retimed it just to double check crank position no air leaks all is new. Thank you for your help..

Posted

after 2 weeks of searching and troubleshooting i found someone on another forum. he was having the same issue he said withafter market cams you change the cam flange lick I did they have a spring and pin behind the clutch on the cam. mine does not have it so you have to remove the decomp system. Just food for thought thank you for your help.

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