2007 50cc lance By silverfox96 (Read 1,843 times)

[silverfox96]

Hey fellas! My neighbor has a 50cc lance scoot, it's her only means of transportation. Hasn't run since Oct of last year. She took it to a guy here in town to get it running for her. He told her just to leave it and over the winter he would get it taken care of. Long story short, it didn't happen. She was told that she needed a new carb. This scoot only has 753 miles/klicks not sure which on it.

She got it back from him yesterday and brought it to me. This is what I've found so far.

It did start, but only with at least half throttle applied. Smoked like hades! white smoke but smelled like gasoline. Accerates on centerstand but very doggy, with some very quiet popping noise.

I shut her down and began to "inspect" the scoot and make an evaluation as to what it will take to get it running properly. First thing I noticed was the airfilter tube was disconnected from the carb. The vent tube from the valve cover is bad and needs replaced. The air filter was very dirty and oil was coming from the intake tube on the filter. Didn't find any oil inside the air filter housing, though but the intake tube was soaked in dirty oil, and had dripped out onto the cvt cover and the filter was very dirty. Checked the engine oil and found it absolutely filthy and way overfilled. Pulled the spark plug to see what condition it was in. It was black and wet with gasoline. However, when I pulled the plug, I thought that I was having a problem with getting the socket on the plug. Took the socket off the ratchet and slipped it on the plug and discovered that the plug was barely finger tight and ready to fall out. (The guy who worked on it said that he had the carb apart 3 or 4 times but couldn't get it to run right.) What I'm thinking, at this point, is I need to get a new plug, a new vaccume hose, change the oil and fill it with the proper quantity, 750ml, clean the air filter element (it's foam), adjust the valves and make sure that everything is back together, tight and fitting correctly, then start it and go from there. I don't think it's the carb that's causing the problem. She told me that when she first got the scoot it had 75 m/k on it, but it would only run about 20 or 25 mph. It got progressivly worse and finally would only run about 15mph. Personallly I'm leaning towards normal maintainence and a valve adjustment and oil change is all that's wrong with it. Got any ideas or suggestions for this situation? Sproket or Alleyoop or Rich?

[sprocket]

Could be the petcock diaphragm is cracked and leaking fuel into the vacuum line and running straight into the intake elbow...

Remove the petcock from the fuel line and just join the hose with a piece of copper tube etc.

Then plug the petcock vacuum hose... then give it a try

[silverfox96]

I'll check that too, Sprocket. Thanks.

[Alleyoop]

Silverfox,
From your post your right on , the loose plug will cause compression loose as well as fouling the plug and running like a dog. Do what you said and then work from there. But I bet after you do all that it will just be minor adjustments and will have a good running scoot.
You can test out the Petcock by just disconnecting the fuel line from the carb and cranking the the motor the fuel should flow out and stop when you stop cranking.

Also I would not take anything to whoever it was taken to the first time.
Alleyoop

[Bashan]

The overfilled crankcase was pushing oil up through the breather into the air filter, that would explain the mess. Then the clogged air filter was dumping all gas into the head which would explain the white gas smoke. I agree with Alley, I wouldn't let that "mechanic" clean my litter box. Rich

[Alleyoop]

HAHAHA, good one rich
Alley

[sprocket]

If the 'litter box mechanic' had the carb apart 3 times.. which I doubt.. he may not have put the diaphragm needle back in it.. that would cause a huge amount of fuel to enter the carb as well...

It would just suck the fuel bowl dry...hence the white smoke...

[Alleyoop]

HAHAHA, And here is was trying to be Diplomatic
Alley

[silverfox96]

The "mechanic" she took her scoot to is the same one that was supposed to help me get that 50cc scoot running that I assembled from 2. He never did show up to help me, so I just dove into it myself.

I sold it a few weeks back. Got 400 out of it. The young man who is riding it tells me every time he sees me what a good running scooter it is.

I started working on this Lance yesterday. Made a list of things I felt needed done to it. I replaced the vent tube, put a new plug in it (dropped the darned plug and it went down inside the cooling housing and couldn't reach it. had to take the fan shroud off and there it lay, right next to the fan!) Hate changing plugs on these scoots! When the neighbor lady got home from work, I called her over to my garage and went over the list with her. Kind of a show and tell. She said she appreciated me taking the time to explain what needed done, but still had no idea or clue as to what I was going to do! LOL

I did check the airfuel mix screw. It was turned out 3 turns, so I bottomed it gently and turned it out 2 1/2 turns. At least that will give me a good starting point for adjustment when I get ready for that. Had to stop earlier than I wanted yesterday. chest pains and pressure. A nitro and a couple of aspirin stopped the pain, but afterwards didn't think it a good idea to continue, besides, the little woman was on my six about trying to do too much at one time. So it might be tomorrow before I get back on it.

[Bashan]

Maybe take a break before the chest pains there SF, we like havin' you around here. Sprocket's comment also made me think maybe the plugged air filter caused an excess of vacuum and lifted the needle=too much gas. Anybody think that's possible? Rich

[silverfox96]

Well, I adjusted the valves on the neighbors scoot. they were tight. replaced the valve cover vent tube and inserted a fuel filter into the end of it and zip tied it up. Installed new fuel filter in fuel line. Charged the battery. Changed the oil. Set the af screw to 2 1/2 turns out, from 3 1/4 out. Cleaned the air filter and the airfilter housing. Discovered that the tube connecting the inlet tubing on the intake filter was broken. I had a used one lying aroung and replaced it. Also plugged the opening for the vent tube from the valve cover. Dang! It's ready to start! The problem is, the starter engages and in less than a 1/4 turn it kicks out. Tried several times to no avail, so off comes the cvt cover! Starter bendix was rusted pretty badly and hard to move so ordered a new one from Mainleyscooters. It'll be here monday around 3pm. The variator pulley (the one with the gear teeth on it) is really discolored and has some deposits on it of some kind. Belt looked good though. Gonna clean the variator up as good as i can with some emery cloth. Hopefully this little Lance will be running by Tuesday.

[silverfox96]

I'm to the point where I needed this scooter to start, so I can adjust the carb. No such luck! Messed with it most of the day, yesterday and finally took the batt to O'Rielly's and had it load tested. Bad Battery! So now have to wait until neighbor can get the money for a new battery. She's got right at 42 dollars in parts in it now. It's a 7 amp battery and the dealer gets 45 for a new one. Her brother told her that I was too thorough and that she should have just had it patched up so it would run! LOL Sorry, but I just don't do things that way. I feel that if it's worth doing then it's worth doing right! Instilled in me by my Grandfather!

[silverfox96]

Well guys, I'm still working on that Lance 50cc of my neighbors. It has me totally stumped. I repaired the air box, the inlet tube was cracked 3/4 way around. Changed the vent tube from the manifold to the airbox. Pulled it off the airbox put a filter in the end of it and tied it up high. installed a new spark plug. Adjust the valves. Changed the engine oil. intalled a new fuel filter. Checked the vaccum operated petcock and it works fine. Starter wasn't staying kicked in so the scoot wouldnt start I installed a new bendix. That didn't do much. Checked the starter and it is ok. Had the battery load tested, it was bad so replaced it with new. Still won't start! Checked for spark by pulling the plug wire off and inserting a new plug in it, grounded it against engine case. Spark varies in color from white to red, no blue at all. Then I checked the pickup. the little metal dot in the center of it was corroded badly. I used some xtra fine emery cloth and cleaned it up.

Started to reinstall the pickup and dropped one of the bolts down behind the flywheel! snit! I couldn't get it to drop out, so it must be caught on something inside of it. Tomorrow I'm gonna pull the flywheel and retrieve the bolt, then reinstall the pickup.

My question is this: Could the corrosion on the pickup have cause the extremely weak and intermittent spark that was present when I checked the coil for spark and would cleaning it with the emry cloth fix the problem?

[sprocket]

It could have but I have seen rusted pick-up coils and they worked fine...

You need to test the voltage going from the stator to the CDI and see if what you get when you turn the engine over...should be above 40 volts AC...50 to 60 ideally...

Check the pulse on the pick-up coil it should be about .5-1 volts every time the coil fires...

But if you have red spark it is either the stator, CDI, ignition coil or high tension wire or plug boot...also check the spark on a bare part of the FRAME.. it could be a bad engine to frame ground.. seen it many times...

The CDI steps up the voltage to about 180 volts and it is fed to the coil where it get ramped to about 18,000 volts...and then fed down the wire to the plug.

The pick-up coil is simply the trigger.. and if you have any spark it is probably working fine...

[silverfox96]

I forgot about the engine ground! When I was adjusting the valves I thought it strange that there wasn't a ground from the valve cover to the frame. Think I'll try that first. Thanks.