Engine wont start? TROUBLESHOOTING GUIDE

[Al.Fisherman]

Well I am 64, and only had kidney stones, tonsils, adanoids and a little high blood pressure, slightly overweight, so I guess i can't let you show me up....thanks for the encouragement...

I'm 65, 5' 11", 220# and working on 15% of my heart. I use starting fluid/throttle body cleaner every time I start the engine for my first ride of the day. I went so far as drilling a small (large enough that the spray nozzle will fit into), on my left side of my filter cover. All starts, less then the length of my PU truck. You can even lower the compression by adding a extra head gasket.

[GoldVeng]

Do you know how many turns the idle set screw on the carburetor should be turned out from its closed position??

[Big Red]

Do you know how many turns the idle set screw on the carburetor should be turned out from its closed position??

As I recall we're talking about a chinese 2 stroke. I don't think it matters if it were something else. There is no precise setting for the idle screw, unless you're looking for a very precise idle speed. Get it running then turn it in to increase idle, turn it out to decrease idle. You just want it to run at an even low idle speed when you're done. Sometimes the chinese 2 strokes idle better when they are warmed up some.
Big Red.

[GoldVeng]

But if it is out to far, it will flood, and that may be the reason the thing wont start..

[GearNut]

Which carb are you dealing with?
CNSv1, CNSv2, NT, NTspeed?
As a generic starting point for any carb screw on any carb, no matter if it is an air screw or fuel screw, is 1 1/2 turns out from lightly seated (lightly seated = carefully screwed all the way in until it stops, not tightened down) . Note this is not in reference to the idle speed screw.
That should get the engine running and allow you to fine tune it from there.

[Big Red]

GoldVeng, Again I'm assuming we're talking about a stock NT carb and a chinagirl 2 stroke. You can take the idle screw all the way out of the carb and it still will not flood the engine, it just wont idle. All the idle screw does is raise the plunger up to where it will idle. It really has NOTHING to do with fuel flow.(EXCEPT AT IDLE.) The screw raises the plunger, which raises the needle, which raises the idle. (Or lowers it, ect.) Thats ALL it does.
And Gearnut, If you set the idle screw, (on a HT with a NT,) against the plunger then back it out 1 1/2 turns, it will not hold up the plunger and make it idle. That will only let the plunger fall all the way to the bottom and the engine will NEVER idle this way.
So GoldVeng, I think I've said this before, Get the engine running, THEN set the idle screw, either in or out, till the thing has a low, sweet idle when warmed up.
Big Red.
P.S. If your engine is flooding your float and shut off needle valve in the float bowl is set wrong, Or there is possibly a little carp obstructing the shut off needle valve.

[GearNut]

GoldVeng, Again I'm assuming we're talking about a stock NT carb and a chinagirl 2 stroke. You can take the idle screw all the way out of the carb and it still will not flood the engine, it just wont idle. All the idle screw does is raise the plunger up to where it will idle. It really has NOTHING to do with fuel flow.(EXCEPT AT IDLE.) The screw raises the plunger, which raises the needle, which raises the idle. (Or lowers it, ect.) Thats ALL it does.
And Gearnut, If you set the idle screw, (on a HT with a NT,) against the plunger then back it out 1 1/2 turns, it will not hold up the plunger and make it idle. That will only let the plunger fall all the way to the bottom and the engine will NEVER idle this way.
So GoldVeng, I think I've said this before, Get the engine running, THEN set the idle screw, either in or out, till the thing has a low, sweet idle when warmed up.
Big Red.

I think you mis-read my post.

[Big Red]

I think you mis-read my post.

Perhaps I did GearNut. If so, Sorry. You are right about carbs that have separate fuel/air adjustments. Those types work by restricting the fuel/air mixture at the adjustment needle. I'm only talking about the STOCK carb that comes with the STOCK chinese 2 stroke. It has only one external adjustment, the idle screw. On THAT carb, NO fuel flows past the idle adjustment screw to restrict. you can take the idle screw ALL THE WAY OUT of the carb, get it running, THEN screw it in untill it idles properly.
I've lost the idle screw on a ride and used the throttle cable adjustment to set the idle so I wouldn't have to keep it revved all the way home. ANY WAY that you can get the plunger to the proper height (for an idle) will work on these carbs. If the idle screw is lost and you adjust idle from the throttle cable you MIGHT want to plug the idle screw hole to keep from sucking in extra air flow, but I've never had that problem. If you set the plunger at the correct height, IT WILL IDLE.(unless something else is wrong.)
Big Red.
P.S. SORRY, You DID say "this is not in reference to the idle speed screw".

[Steve Faber]

ok I have read and read and read in this thread but not sure if the answer is in it. my issue is this , the other day I was riding and got hit by a huge rain storm carb sucked in water had to walk the bike about 1/2 mile before rain stopped and I was able to get bike started on a hill to get home. had rain for a couple more days so had the bike parked . yesterday I tried to get the bike going and as long as I don't hit the throttle it tries to start until I throttle on then it bogs down . I have checked fuel flow and spark ( plug was very black ) I WD40ed the throttle and clutch cables to be sure they weren't sticking I pretty much stripped the whole engine and connecting parts off the bike and reinstalled them all . I am at my witts end on this issue and really need a solution.

[Steve Faber]

ok well I took a shot that something was wrong in the spark system and I had an old chainsaw , so I cut off the wire that connects to the plug and attached it to the wire off the CDI and now it runs woohoo. I guess the wire itself can be an issue .