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General => General Discussion => Topic started by: blue on September 11, 2014, 02:24:21 AM

Title: scoots down
Post by: blue on September 11, 2014, 02:24:21 AM
Scoots down cant find out whats wrong.time to sale for parts.and get new.
Title: Re: scoots down
Post by: tortoise on September 11, 2014, 02:39:39 AM
cant find out whats wrong
What engine, and which of the fuel-spark-compression related elements is deficient?
Title: Re: scoots down
Post by: blue on September 11, 2014, 09:56:59 AM
Its a gy6 50 cc has spark and compression and geting gas.the last few mornings its been starting hard.I replaced the carb and still nothing.valves have been checked.and new battery.thinking its something in the wireing. Maybe cdi.
Title: Re: scoots down
Post by: tortoise on September 11, 2014, 12:40:28 PM
gy6 50 cc has spark and compression and geting gas
If no intake manifold vacuum leaks, check timing . . sometimes the flywheel woodruff key will shear.  Insert a mini-screwdriver into the spark plug hole to determine when the piston is at top-dead-center while rotating the cooling fan . . then verify flywheel and camshaft sprocket timing mark alignment.

ValleyScooterParts offers free shipping over $15 . . so a replacement stock CDI and ignition coil (http://www.valleyscooterparts.com/elpa2.html) would cost around $20.  ScrappyDog offers just the trigger pickup coil (http://www.chinesescooterparts.com/GY6-ignition-trigger-pickup-0122-08.htm?categoryId=-1).
Title: Re: scoots down
Post by: 2wheelfun on September 11, 2014, 12:43:26 PM
If it's getting spark the CDI will not be bad. Is it a strong blue spark or weak yellow spark? Those cheap spark checkers from HF work really well for testing. Old plug hooked up and layed against a ground works well too.......is the plug wet after trying to start it? Does it fire up if quick start is sprayed into the air intake then die?
Title: Re: scoots down
Post by: blue on September 11, 2014, 01:01:09 PM
Nice blue spark.and plug is wet.ill try to adjust timeing and valves again just to make sure.
Title: Re: scoots down
Post by: blue on September 12, 2014, 02:16:33 AM
Its the stator I have no power come from it when motor turns over.
Title: Re: scoots down
Post by: BettinANDlosing on September 12, 2014, 04:03:41 AM
Nice blue spark.and plug is wet.ill try to adjust timeing and valves again just to make sure.
If the spark can jump a 1/4" gap and the plug is wet you rich, puke rich. What's your jetting and any mods ?
Title: Re: scoots down
Post by: blue on September 12, 2014, 04:19:49 PM
Oh no it might be to rich.I did put a bigger gas line on.ill go back to a smaller one and try that.
Title: Re: scoots down
Post by: BettinANDlosing on September 12, 2014, 07:03:16 PM
Fuel line size makes no difference in jetting.
Title: Re: scoots down
Post by: zombie on September 12, 2014, 09:52:29 PM
+ one on the woodruf key. I've had a few slip/shear.
I'd do a compression test too. Maybe a burnt exhaust valve.
Title: Re: scoots down
Post by: blue on September 13, 2014, 12:56:35 AM
Compression is over 120 .mmmmm has to be something in the wireing.if valve is burned would I still have that good of compression.
Title: Re: scoots down
Post by: tortoise on September 13, 2014, 01:25:02 AM
has to be something in the wireing
AC or DC-CDI ignition system?
Title: Re: scoots down
Post by: blue on September 13, 2014, 01:46:11 AM
AC or DC-CDI ignition system?
   dc
Title: Re: scoots down
Post by: zombie on September 13, 2014, 03:50:53 AM
Compression is over 120 .mmmmm has to be something in the wireing.if valve is burned would I still have that good of compression.

The compression would feel good by hand or sound good on the electric start but it would never read good on an accurate tester.
If you have spark it cannot be a wiring issue.
I had one scoot that had the same problem. It went to three shops before the gal found me. I looked at the thing for three days before I thought of the crank key, and as soon as I put my hands on the flywheel/rotor, it spun on the crank.
Pulled the nut off, and found the key had sheared off level. I guess what happened was the nut loosened just enough for the rotor to slip. It's worth looking at.

One other thing I have done is put a socket in a 1/2" drill on a 6" x 3/8" extension and use the crank nut, and drill as an electric starter. Do this with a timing light, and the plug removed. It will spin the engine fast enough for you to read the timing marks.
Title: Re: scoots down
Post by: blue on September 13, 2014, 04:49:46 AM
Thanks zombie.I will check that out in a few days.im off work next week for vacation so ill have time then.
Title: Re: scoots down
Post by: zombie on September 13, 2014, 06:43:02 AM
That's what Vaca is for... Fixing all the sh** that breaks during your work life.
Who made this system up?
Title: Re: scoots down
Post by: blue on September 14, 2014, 07:05:43 PM
Geting to the end of the rope with yhis scoot.I have spark.but week out put from stator.if the elec.relay is bad would that make the stator week.my guess is no.
Title: Re: scoots down
Post by: zombie on September 14, 2014, 08:27:49 PM
If you have spark at all it is not the stator.
Title: Re: scoots down
Post by: blue on September 15, 2014, 02:14:59 AM
Looks like ill be pulling the head off for closer look.
Title: Re: scoots down
Post by: zombie on September 15, 2014, 03:10:54 AM
Use a LONG straw, like one of those giant fountain drink straws, to direct the spray from Brake Clean or Carb clean into a glass. Once you have about one ounce pour that into the upside down heads ports one at a time (intake/exhaust) If any of that cleaner weeps thru the valve(s) you know where the problem is.
Title: Re: scoots down
Post by: BettinANDlosing on September 15, 2014, 07:13:19 PM
If you have spark at all it is not the stator.

The primary coil in the stator can be bad, i have a bike in the shop right now that does have spark but its super weak, won't even jump a few millimeters to ground. The primary coil was only putting out 40v ac.
Title: Re: scoots down
Post by: 2wheelfun on September 15, 2014, 07:26:42 PM
Do you know what the stator voltage a/cv should be, if 40vac is too low?
Title: Re: scoots down
Post by: blue on September 15, 2014, 11:52:18 PM
Tryed a new coil.got nothing did the same thing.im thinking bad valves.
Title: Re: scoots down
Post by: BettinANDlosing on September 16, 2014, 05:31:24 AM
Yeah from what I understand 50v ac will work but its weak, your want 100v ac ideally out of the primary coil.