I'm stumped! No start!
#1
I'm stumped! No start!
Hello,
I have a 2003 Sunl 150cc. Gy6 engine. When I bought it, it was well-used with a no-start, no spark condition. I installed a new CDI (it had none) New Champion spark plug, fixed a shorted kill switch. I now have spark when the plug is grounded to the block. Had a leaking carb, so I got a brand new replacement and put it on. Still no start. Not so much as a pop. Set the valves to .004. Still nothing. Seems to have good compression. Shot some starting fluid in the carb. Still not a pop. I even removed the plug and shot a little in there. Still nothing. The gas line is clear and the carb seems to be filling. The only thing I can think of is maybe the rubber carb boot to head is leaky. I'm doubting that this will do it and I hate to just throw more parts at it. I'm stumped. Any ideas would be appreciated.
Thanks, Tom
I have a 2003 Sunl 150cc. Gy6 engine. When I bought it, it was well-used with a no-start, no spark condition. I installed a new CDI (it had none) New Champion spark plug, fixed a shorted kill switch. I now have spark when the plug is grounded to the block. Had a leaking carb, so I got a brand new replacement and put it on. Still no start. Not so much as a pop. Set the valves to .004. Still nothing. Seems to have good compression. Shot some starting fluid in the carb. Still not a pop. I even removed the plug and shot a little in there. Still nothing. The gas line is clear and the carb seems to be filling. The only thing I can think of is maybe the rubber carb boot to head is leaky. I'm doubting that this will do it and I hate to just throw more parts at it. I'm stumped. Any ideas would be appreciated.
Thanks, Tom
#7
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#8
what gap are you using anyways? have you tried pinching it down a little?
#9
Join Date: Dec 2008
Location: Tracy, California, USA
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Well I am stumped too. Spark, Fuel, Compression. With all of those it should start.
I would revisit all the things you've done again with a fresh outlook just in case you missed something. Check the spark again, valve adjustment, etc.
Check the ignition timing with a timing light. There is a rubber access plug on the flywheel cover to allow the timing light to shine through to the marks on the flywheel, though I've found it easier to remove the flywheel cover to get a better view. Although rare, I've seen people report sheared keyways which allow the flywheel to rotate on the crankshaft and fire the plug at drastically the wrong time. I've also seen reports where the CDI self triggers and fires erratically (and at the wrong time).
Else I'm out of ideas at the moment...
I would revisit all the things you've done again with a fresh outlook just in case you missed something. Check the spark again, valve adjustment, etc.
Check the ignition timing with a timing light. There is a rubber access plug on the flywheel cover to allow the timing light to shine through to the marks on the flywheel, though I've found it easier to remove the flywheel cover to get a better view. Although rare, I've seen people report sheared keyways which allow the flywheel to rotate on the crankshaft and fire the plug at drastically the wrong time. I've also seen reports where the CDI self triggers and fires erratically (and at the wrong time).
Else I'm out of ideas at the moment...