1999 DS won’t fire

[nwocart]

Was doing a lap at WOT around my yard last night. Cart died so I toook plug out and check it and saw I was getting no spark. Bought new plug today , checked spark and it was good. Put it in and it tried to fire ONCE (barely). motor turns over but doesn’t try to fire at all. I wonder if it isn’t a fuel issue now? Any ideas? I have to work today so I can’t mess with it till later but figured I’d post here. Thanks

[Fairtax4me]

A failing rev limiter or coil can give a weak or inconsistent spark that is not enough for the engine to run. When you check for spark, crank the engine for several seconds and watch to see if you have consistent bright blue spark the whole time. Often a failing coil will give one or two good sparks and then it will taper down to barely making a spark at all and it will appear very dim and yellowish color. A bad rev limiter usually just results in having no spark at all, or having good spark that comes and goes, with no real middle ground.

Try unhooking the rev limiter box ground wire first. It’s the brown wire that is bolted to the rev limiter mount bracket. Check for spark, and See if that allows the engine to run. If you still have a weak or no spark, find the white wire with black stripe that runs down the right side (belt side) or the engine. Disconnect that at the bullet plug that is right next to the rev limiter. That is the kill circuit wire and disconnecting it will remove the micro switches and key switch from the ignition kill circuit. Recheck for spark. If you still have weak or no spark, this will rule out a possible switch or wiring problem and confirm if the coil is faulty.
If the engine runs with the kill circuit disconnected, you will have to manually ground the Black wire from the coil to kill the engine. It will not shut off on its own.

[nwocart]

Originally Posted by Fairtax4me

A failing rev limiter or coil can give a weak or inconsistent spark that is not enough for the engine to run. When you check for spark, crank the engine for several seconds and watch to see if you have consistent bright blue spark the whole time. Often a failing coil will give one or two good sparks and then it will taper down to barely making a spark at all and it will appear very dim and yellowish color. A bad rev limiter usually just results in having no spark at all, or having good spark that comes and goes, with no real middle ground.

Try unhooking the rev limiter box ground wire first. It’s the brown wire that is bolted to the rev limiter mount bracket. Check for spark, and See if that allows the engine to run. If you still have a weak or no spark, find the white wire with black stripe that runs down the right side (belt side) or the engine. Disconnect that at the bullet plug that is right next to the rev limiter. That is the kill circuit wire and disconnecting it will remove the micro switches and key switch from the ignition kill circuit. Recheck for spark. If you still have weak or no spark, this will rule out a possible switch or wiring problem and confirm if the coil is faulty.
If the engine runs with the kill circuit disconnected, you will have to manually ground the Black wire from the coil to kill the engine. It will not shut off on its own.

Put a new plug in , cranked for 15 seconds , have consistent blue spark.

Took like off carb and turned motor over , fuel pump Spears to be working fine. I’m going to try and pull the carb and clean that, maybe a stuck float or something

[nwocart]

I’m not too familiar with these carbs but when I pulled the jets out, the small one with the threads was plugged. Got it cleaned out gonna try it later

[nwocart]

update: cleaned carb, the smaller jet (the one that threads in to hold the long jet in) was plugged, now it runs good. must have some crap in my fuel

[CP241]

I'd pull the carb apart and give it a good bath in an ultrasonic cleaner full of gunk carb cleaner. Nothing else works nearly as well

[nwocart]

Originally Posted by CP241

I'd pull the carb apart and give it a good bath in an ultrasonic cleaner full of gunk carb cleaner. Nothing else works nearly as well

been eyeing one of those, have heard good things about them especially in regards tokeeping carbs clean. I like to mess with old three wheelers and I have fought some nasty carbs. I don't have as many trikes any more so I haven't bought one, but I think they clean most small parts really well

[CP241]

Does a fantastic job. I think the one I got is a 2L one for like 80 bucks. It's got the heater and timer to shut off automatically. I've made some really nasty parts look brand new with it. Just disassemble, drop it in, let it go for about 30 minutes while you work on something else. Then pull it out (careful, it's hot!) blow it out with compressed air and reassemble. Never had one not work. IT also does a great job on some of the old 3/4 wheelers where the jets may strip out if you try and remove them (you know what I'm talking about!). I just leave those in and hope for the best, maybe give it a second 30 mintues depending on how bad it is. I've never had one not work :)

I use the basket that comes in the Gunk! can in the U/S cleaner. It's got smaller holes and doesn't lose the little jets and things. The basket that came with mine is just large mesh and wouldn't really work well, i threw it in the trash.

[crash12888]

When cleaning dirty carbs, alot of people tend to overlook the fuel tank and even the gas can(s) they fill there carts with.
I always clean the complete fuel system and mention to customers to really check their gas cans.

Cleaning the tank is easy enough, fill at least half full, jack up cart to get sediment/trash to run to one end, use 3/8 or 1/2" hose to siphon fuel. hose in bottom of tank will vacuum out trash at same time.

[nwocart]

Originally Posted by crash12888

When cleaning dirty carbs, alot of people tend to overlook the fuel tank and even the gas can(s) they fill there carts with.
I always clean the complete fuel system and mention to customers to really check their gas cans.

Cleaning the tank is easy enough, fill at least half full, jack up cart to get sediment/trash to run to one end, use 3/8 or 1/2" hose to siphon fuel. hose in bottom of tank will vacuum out trash at same time.

I know that that is something I should take heed, my tank has some bits floating around in there from years of having gas thrown in it by the rental company. Ill get around to it at some point, have an inline filter ready too figured I should do it all.