No start issue

[ConwayMuddy]

Having a no start issue, kart is a yerfdog dog 3206 with a 150c.c. Back over summer the kart died and wouldn't start, no clicking or anything. Now that it's winter I'm finally digging into it. Replaced the starter solenoid, no change. The brake switch is bypassed. If I use a test light, I have power at both sides of the fuse holder. I have no power at the on/off switch, no power at the push button start, and no power at the brake switch.

Since I'm electrically stupid, could it just be a bad ground? I found a main on the motor but haven't seen another. It also looks like the on/off either sends or receives power from the cdi, is it possible that my cdi is cooked?

Any help (speak slowly and simply) would be greatly appreciated. I'm beyond frustrated

[ConwayMuddy]

Found that the power wire going to the brake switch was broken at the plug, under the electrical box cover. Fixed that, if I connect a test light to the bullet connector before the switch, to ground it lights up. If I probe the connector to the wire from the brake switch to the push button, no light. Checked the on/ off switch, no power, didn't think to check the start button.

[xlint89]

Welcome to the site.

So did you solve your problem?

I was going to say check your grounds.

Broke my engine to frame ground once and replaced the starter for nothing. Elec connector snapped so no juice to starter, no click, nothing....

[ckau]

Yep! Check those ground points! Poor or broken grounds are probably the most frequent cause of failure in the whole wiring circuit. The yerf harness is poor at best, inadequate wire size, cheap pin connectors, just plain problematic in general. Bad ground points cause all sorts of issues, Slow or no starter spin, hard starting, misfires or ignition skip and dead batteries. Many a time starters , cdi's, carbs and batteries have been replaced only to find a faulty ground.
you can cure a lot of electrical issues by creating a solid ground terminal. Follow the negitive wire from the battery up to the electrical box on the swing arm. It will most likely be twisted together with some other ground wire going to the starter solenoid, rectifier, and ignition. Find a accessible spot on the electric box metal base. Drill a hole for a 1/4-20 x 3/4 bolt. Make sure the wire from the battery is 10g or larger. Connect from the battery to this bolt using a steel eye lugs. ( aluminum lugs will crush and break)you now have a solid ground terminal to work from. From this bolt run another 10g wire to one of the starter mounting bolts on the motor. You now have a strong ground to the motor for starting, charging and ignition coil. run another 12g wire up front to the dash area. This is a ground terminal for the ignition /starter switches and accessories. The 12g wire running forwards bypasses some problematic connections, (like that brake safety switch) and stream lines the negative path. Using terminal points helps with future electric issues by creating a test point for diagnostics. I.E... the CDI is controlled by ground. By grounding out the cdi it shuts off. The ignition switch sends ground to the CDI. A ground short anywhere in the circuits shuts the CDI down. Many a CDI has been replaced thinking it's bad.
I removed the electrics totally from the swing arm and located everything in a box on the chassis behind the seat. There is a negative terminal point and a positive fused terminal point. All the circuits, starting, ignition, charging, lights and oil cooling are run from these terminals. A failure in one circuit won't effect the others. Another helpful addition is a kill switch with a removable handle at the battery. This prevents battery drain while not in use. This switch shuts everything down! Also serves as a safety kill or a anti theft device.

[ConwayMuddy]

The broken wire was repaired and the kart started and ran, briefly... I was able to rip around for about 30 minutes, parked it. The next day it started but ran funny and died after a few minutes. Now it won't fire up.

I checked and I'm getting gas to the carb, It also had spark when I checked the plug against the valve cover. It sounds l8ke it wants to fire but mostly cranks over.

I did notice I had the wires on the on/off switched. Swapped them around, but I'm unsure if the ground should be the middle of the 3 terminals or the one farthest from the on position?

Now I also have to have the headlights connected for the motor to crank. They were unplugged all summer and it was fine so I'm confused as to how that changed.

Currently the battery is grounded to the engine block and the other grounds under the electrical box are also ran to the block if I recall. I checked both connections and they were clean and tight.

[TigerBuggy]

Fellow Spiderbox owner here. Any luck sorting out the engine/electrical issue?

[ckau]

you got electric gremlins, Typical on those yerf wiring harnesses. It's as though the electrics deteriorate after some years, everything falls apart! Here's a basic yerf wiring harness schematic. Follow through and double check everything.

[ConwayMuddy]

Checked again tonight, still have spark. Going to check the wiring again tomorrow. Don't know why the headlights would need to be connected for it to crank. After I check wires again I guess I'll be pulling the carb. Best guess since it has spark and fuel to the carb, fuel isn't getting through the carb.

[ConwayMuddy]

Pulled the carb apart today, was stupid clean. Cleaned out everything anyway. Kart starts but I don't know how it will run. Took a guess as to where the mixture screw should be. Says to lightly seat and then back out 1.5 turns, don't know how you tell if it's seated or not? Also figured out the ground has to be on the middle terminal of the on/ off switch or the kart won't shut down.

Not electrical but anyone have any advice on getting a stock carb to clear stuff when it's on a 30mm intake? According to b.d. it's a guaranteed fit that may or may not work... the fuel bowl and drain line hit the bolt that holds the engine in the cradle, if I raise the carb up it wants to flood out. Have a uni filter I want to put on so I don't suck junk into the carb...

Happy new year and thanks for the help.

[SYCARMS]

I would just run your stock intake. The 30mm intake is angled up as compared to the stock and will be of no value as to power gains. The stock intake will require you to make up a red neck cold air intake from carb to air filter.

[xlint89]

The idle air screw is "bottomed out" when you can't turn it IN any more. Turn it in GENTLY as you do not want to damage the tip of the idle air screw. It is a precise metering device and deforming the tip by over tightening it will cause you carb adjustment frustration.

So, turn it IN until is stops. (gently) Then turn it OUT 1 1/2 turns to start. Once the engine is warmed up adjust the screw IN and OUT 1/4 turn at a time looking for your MAX RPM. Once you find the best RPM, try turning the screw 1/8 of a turn to obtain the absolute best RPM.

Once that is achieved, reset your idle RPM by adjusting the throttle position screw to your desired RPM.


While adjusting the idle air mix screw, if you find the best RPM is with the screw turned all the way IN, you need to go down 1 jet size on the pilot circuit. If you find the best idle is with 3 full turns of the screw OUT or more, you need to go UP 1 or more jets on the pilot circuit.

And I will agree with Tom on your intake manifold Q. However, I will also add if you want some performance, match up your intake manifold and head ports. Also clean up any casting slag inside the opening. If the air flows smoothly into the head with no obstructions you should see a slight gain in performance for FREE.

[ConwayMuddy]

Not really looking for performance gains with the intake. I just wanted to replace the stock, cracked one that didn't really stay tight on the carb anymore.

I set the idle air screw close to where it was before I removed it. Seems alright, starts about as well as it always did. Have to mess with the throttle stop since the kart wanted to roll when idling.