• Spark but doesn’t crank over

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 #13486  by Alexmeza
 Sun Apr 28, 2019 2:45 pm
I have a Yerf Dog spiderBox GY6 that has been sitting for quite some time. Initially it had a bad intake manifold & was running rough. It got parked and didn’t get messed with for a couple years. I went ahead and changed the oil, gas & installed a new the carburetor, intake manifold, starter solenoid, battery, tested starter (was good) . It was cranking ( lights came on)but realized there was a short & wires being old a brittle I went ahead and ordered the engine wiring harness, a new cdi & engine start switch. Installed & tried turning it on over. It cranks (lights don’t turn on) but still hasn’t turned over. I grounded the spark plug & did indeed get sparks. I also ordered the stator and tool to remove the flywheel but haven’t been able to remove the nut on the flywheel. Does the flywheel have a certain position it needs to be & or if moved do valves need to be adjusted? I’ll try again after the stator is replaced & maybe a new plug & with starter fluid see if it’ll turn over but stuck on what else to try. I should mention the connection that requires the brakes to be pressed in is also bypassed. Any help appreciated
 #13524  by stevrigg1
 Sat May 04, 2019 10:21 pm
before you do surgery,,, if the engine "cranks" then it is turning over. I think you are trying to tell us that it won't fire
or show any attempt at starting.
there are three things that make an Otto engine work. wind fire fuel. "wind" can be checked with a compression gauge!
fuel is the hardest to prove! "fire"is simple enough if you are willing to hold the spark plug and crank the engine!!!
if you have fire you will NOT be happy you did this, as there are easier ways to do this, though I have seen the untrained say "no spark" even when there was. in many cases these engines have no spark due to bad grounds. read the testing laid out in the forum(follow the tests according to what they tell you to do) and in the majority of cases you will have a running machine very soon.
 #13540  by Alexmeza
 Thu May 09, 2019 10:48 pm
Yes the GY6 howit engine will not turn over! I just went ahead and changed the magneto stator & still won’t fire up. There is spark. I’ve tested by holding & grounding. Don’t currently have a compression gauge. I have a new carb and gas lines & nearly all new electrical components as stated above. I noticed that I wasn’t getting current from the stator magneto to the cdi (head lights, ground and a red cable). Even with the new magento. I appreciate the response.