|
|
Post by zfjelstad on Sept 21, 2012 12:00:27 GMT -5
Last night I adjusted the mixture screw on the carb while the engine was warm and I thought I had the perfect setting. This morning when I went out to start the scooter cold, I wasn't able to get a spark. I haven't tried it this time yet, every time I mess with the gas flow or carb mixture screw on my MC-54-250b, I have trouble getting a good spark when starting the scooter cold. I change out the spark plug and it fires right up. I'm just rotating between two spark plugs. Is this a sign of a bad coil?
|
|
|
|
Post by richardthescooter1 on Sept 21, 2012 13:00:34 GMT -5
It could be a bad coil, what did your spark plug look like?
|
|
|
|
Post by carasdad on Sept 21, 2012 13:15:31 GMT -5
|
|
|
|
Post by richardthescooter1 on Sept 21, 2012 13:34:38 GMT -5
Awesome info carasdad, thanks.
|
|
|
|
Post by zfjelstad on Sept 25, 2012 12:46:08 GMT -5
So I know that I am getting proper spark to the engine, because I hold the spark plug against the engine block and it sparks on time along with the turning of the engine. Just to remind you, I had the scooter running beautifully until I decided to mess with the mixture screw on the carb. I had the mixture screw fully tightened down before I decided to mess with it. It seems that the mixture screw being fully tightened was the only setting that the scooter would run with power. This was after I had changed the vacuum lines and the fuel filter. After adjusting the mixture screw out about 1 full turn, the scooter was still running very well, however it was nice and warmed up while I was adjusting. I came back to the scooter the next morning and I could not start the scooter; it would fire a couple of times in the first couple of seconds and then nothing. I checked the spark plug and it was completely soaked but it was still getting spark as said before. I checked the carb needle on top and it was moving in and out without without tension. I never messed with the idle screw. My air intake seems to be working just fine without any hassle as well. Where do I go from here?
|
|
|
|
Post by barnie on Sept 25, 2012 14:14:35 GMT -5
No chance you have a vacumn hose crossed?? If it ran very good with the air/fuel screw closed, I think i would just leave it alone. I have a jcl with the linhai 257 in it and it doesn/t make much difference where I thurn the screw to so i just leave it at 2 1/2 turn out. Yours may act similar. Sounds like you are getting just to much gas on the start circuit.
Barnie
|
|
|
|
Post by zfjelstad on Sept 25, 2012 14:33:25 GMT -5
I know that the vacuum lines are more open than they were before since I replace them with quarter inch fuel lines from the auto parts store, and that vacuum line splitter I replace with a 3-way quarter inch brass splitter. I don't think I crossed ay vacuum lines since I replaced them one at a time. Are there any techniques to overcome this flooding issue at the start? I know once I get it started it should run fine as before.
|
|
|
|
Post by richardthescooter1 on Sept 25, 2012 14:36:57 GMT -5
What do you have that set, lean or rich. I have the mc-54-250b scooter, my needle jet clip is set to the highest of rich, my carb is 2 1/2 turns out. Hard starting can also be a vacuum leak or a loose intake clamp. vacuum line should be 3/16, they may be to big? just a thought. Attachments:
|
|
|
|
Post by zfjelstad on Sept 25, 2012 14:49:38 GMT -5
That is a good thought about the vacuum line size. The scoot wasn't getting enough fuel before I change the filter and vacuum lines and I just chose the size of the vacuum lines based on the size of the fuel filter receivers. Now I'm definitely getting a lot of gas since the spark plug is wet after trying to start; before it would always come out dry. I never thought about the needle setting. I'm sure it hasn't been changed from its original setting, so I will check on that. Does richer mean it's going to allow more gas? Maybe if I'm getting too much gas, I should adjust to more lean?
|
|
|
|
Post by prizmm on Sept 25, 2012 14:52:41 GMT -5
vacum lines why ? only line i have is for my mikuni fuel pump,, plugged the rest
|
|
|
|
Post by richardthescooter1 on Sept 25, 2012 15:16:11 GMT -5
I'd would first switch back the vacuum lines and then try starting scoot before you do anything else, then if you need to check your needle jet check it before you adjust a/f, I see you live in an area that gets cold, these scoots need to be richer in cold whether. The only line I have that is qauarter inch is my fuel line and from gas tank to fuel filter, and fuel pump.
|
|
|
|
Post by zfjelstad on Sept 25, 2012 16:25:31 GMT -5
Maybe it's cold for someone from the east coast.  |
|
|
|
Post by richardthescooter1 on Sept 25, 2012 16:49:25 GMT -5
I was out there two summers ago and it was pretty cool at that time of the year. Let us know how you make out.
|
|
|
|
Post by zfjelstad on Oct 8, 2012 12:28:53 GMT -5
Well I went back to my old trick and it work. I just changed out the spark plug and it fired right up and works just as fine as before. However, I think I'm getting horrible gas mileage, because when I ride it, I wreak like gas fumes afterward, as if I'm driving a two-stroke. I have the carb needle at the mid-range between rich and lean, and the mixture screw is tightened all the way. If I loosen the screw at all, I only get about have the power. Do I need to adjust the needle to a leaner setting? Will that improve my gas mileage?
|
|
|
|
Post by zfjelstad on Oct 8, 2012 12:29:43 GMT -5
half the power, not have.
|
|
|
|
Post by WarrenS on Oct 8, 2012 16:17:56 GMT -5
The enrichener is probably not extending and shutting off the extra gas when it gets hot. Or it could be a float problem.
|
|
|
|
Post by macktheknife on Oct 8, 2012 17:08:50 GMT -5
This is another case where the GY-6 stator, CDI and coil test does not apply this is a 250 system with different outputs and a different type CDI. Great 250 troubleshooting here: |
|
|
|
Post by zfjelstad on Oct 8, 2012 18:34:36 GMT -5
I went out on a limb and adjusted my needle one notch to the lean side. I restarted the scoot and it fired right up. I then loosened the mixture screw one half turn and I can't smell the fumes nearly what they were before. I hope it lasts. We'll go from there.
|
|
