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Discussion Starter #1
I've got a 98 foreman 400 and I just changed the timing chain and rebuilt the top end while I had it off. I've got everything timed correctly and back together the way it should be but for some reason now the starter drags pretty bad with a fully charged battery unless I remove the air box lid or spark plug. It's getting fuel and fire but it won't even try but did back fire one time when I held the throttle down for a couple seconds. I'm at a loss... Any help will be greatly appreciated.


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What do you have for compression in PSI? My guess is that you have a bent valve. It is best to use your hand (not the starter button) to gently motor the engine through after reassembly for its first few rotations.

Rick
 

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Discussion Starter #4
I used my hand until I felt the compression build up. I don't have the right fitting to use my compression checker but my felt like it had plenty. I still don't understand why the starter would quit dragging if I remove the air box lid or spark plug. I did clean the carbon off of the head and clean the valves and the lap them and they were not bent


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One of two possibilities here. 1. You did something wrong which would require a complete disassembly. 2. Something failed during the disassembly process unrelated. #2 seems unlikely. However a weak battery, corroded or loose battery connections or a bad starter can exhibit these symptoms. #1 seems more likely.
 

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I've got a 98 foreman 400 and I just changed the timing chain and rebuilt the top end while I had it off. I've got everything timed correctly and back together the way it should be but for some reason now the starter drags pretty bad with a fully charged battery unless I remove the air box lid or spark plug. It's getting fuel and fire but it won't even try but did back fire one time when I held the throttle down for a couple seconds. I'm at a loss... Any help will be greatly appreciated.
What was done to 'rebuilt' your topend? Machining & parts...?

Did you put the new chain on while following the FSM?

This is a guessing game at best so far... not enough info yet...
 

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Discussion Starter #8
I replaced the jug, the piston, cleaned the carbon off the bottom side of the head and valves. Lapped the valves, changed the valve seals. After I changed the timing chain because I had to remover the top end to remove the chain tensioner anyways.


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Thanks, were the brand new cylinder & new piston & rings, OEM Honda? Were any of those were aftermarket? Please bear with me... I don't like to guess if I don't have to.
 

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Discussion Starter #12
The jug is stock the piston is aftermarket. Those were installed before the timing chain and it did run before it just needed the carb tuned. I did the work on the head after I replaced the timing chain before I reinstalled it


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The most likely fault is the cam timing then... assuming everything is installed right, with new gaskets, etc. And assuming the ground cable got put back on the motor and is clean and tight.

You may have to loosen the valve adjusters up and pull the cover off from the head and go through the cam chain installation/timing procedure in the service manual again. Can't really help you much... too many things could be wrong with parts fit & assembly to be guessing about it.
 
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