02 426 Motor Locked Up


3 replies to this topic
  • KodiakGreen

Posted December 17, 2007 - 05:51 PM

#1

02 426 I was luggin the motor and the bike died I went to restart and the compression relase had no tension, after playing with the lever i finally got some tension out of it. I got the bike started and it idled for 30 seconds then made a loud deep sounding ping and just died. I drained the oil and inspected oil filter neither had any metal shavings. Its not locked up I can kick it through but it wont fire.

  • brt 426

Posted December 18, 2007 - 04:16 AM

#2

If the exhaust valves are open then your decompression cable will be slack. But that's not to say that the exhaust valve was stuck open and pulling on the cable hasn't released it. If that's the case then the exhaust valve hitting the piston would give you a noise like you described. Pop of the cam cover and check your clearances. If the valves are bent or stuck open you will have a large clearance on the offending valve/s.
When you kick it , does it have compression as usual? If not , can you hear air leaking out the exhaust or intake when kicking it over.
I would stop trying to start it till you have checked the valve area. Hope this helps.
Goodluck

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  • rdbermshot

Posted December 18, 2007 - 03:42 PM

#3

you didnt tell us if it had any compression--just that it would turn over---mine used to kick over but no compresson-then it would have some like a sticking valve or cable-but it would always start------your cam chain adjuster and chain may have caused it to jump time and you now have bent valves thus no compresson----i have rebuilt many and the highest wear areas are the cam chain and the small sprocket on crankshaft for camchain--- hey dig this---friend changed his oil and put a sign on seat saying no oil---he took sign off of bike to load up to ride---never put any oil in the bike---rode the bike for a good 20 min.--bike never seized up---he was sick---we tore that whole motor apart looking for bad stuff---replaced the crank and that little gear and cam chain look the worse......thats allfolks

  • sirthumpalot

Posted December 18, 2007 - 05:41 PM

#4

Lugging then a clunk on an older (worn) motor, my guess is the timing chain slipped a tooth or two because it was loose or because the crank sprocket was worn (or both). I recommend checking the valve timing, if it's off then I'll bet that's what happened.





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