1986 lt50 dying`

[morley8065]

Hi everyone, I am new here. i just bought my 4 year old a 86 lt50, ran like a champ for 2 days, I mixed up some new gas for it yesterday, and still ran fine, but today it would run out for a few seconds then die.....nothing has changed since last night, but it is throwing fuel out the air cleaner side and not wanting to run at all, i can get it to start after a few pulls, it will idle, but give it gas and dies.......any help would be appreciated, thanks/...the guy i bought it from said the carb was rebuilt, thanks

the previous owner ran it on 32:1 and amsoil syn. i didnt mix amsoil syn, but tried to get pretty close to 32:1.thanks

[VAL]

Originally Posted by morley8065

Hi everyone, I am new here. i just bought my 4 year old a 86 lt50, ran like a champ for 2 days, I mixed up some new gas for it yesterday, and still ran fine, but today it would run out for a few seconds then die.....nothing has changed since last night, but it is throwing fuel out the air cleaner side and not wanting to run at all, i can get it to start after a few pulls, it will idle, but give it gas and dies.......any help would be appreciated, thanks/...the guy i bought it from said the carb was rebuilt, thanks

the previous owner ran it on 32:1 and amsoil syn. i didnt mix amsoil syn, but tried to get pretty close to 32:1.thanks

Sounds like a stuck float or needle valve.

Did you shut off the fuel valve last night when you put it away.

[morley8065]

i dont think i shut the fuel valve off when i put it away that night.....is that a no-no...i just took the carb off and was going to try and clean it...any suggestions or things to do or not do....thanks

[VAL]

Not many needle valves can keep the carb from overflowing it the motor is not running and the fuel valve is left open. You said that you had fuel coming out of the Air cleaner this would indicate that the carb has flooded. (I dont understand why you didnt see a puddle of fuel on the floor though. We can addresss that later)
Before you do anything, just drain the carb. There might be a small recessed scew at the base of the carb bowl bottom next to a hose. If its there, make sure the fuel is turned off and then unscrew the screw until fuel exits the carb through the hose. Good ides to have something under to catch the fuel. Once it stops flowing, turn the screw in to close the drain. Open the fuel again and start the motor. It may take running the motor with the fuel off until the motor clears out. If it clears out then open the valve and have fun. Make sure to turn off the fuel everytime you stop the bike. If this doesnt work, post again and we can go further with the issue.

[morley8065]

ok, drained carb, tried to start nothing, have spark, but after about ten pulls, i can see fuel dripping out the air cleaner side, (air cleaner is still removed for now)...not even thought of firing......i even drained the bowl a few times but nothing...even switched out plugs.....i am lost....

[VAL]

Originally Posted by morley8065

ok, drained carb, tried to start nothing, have spark, but after about ten pulls, i can see fuel dripping out the air cleaner side, (air cleaner is still removed for now)...not even thought of firing......i even drained the bowl a few times but nothing...even switched out plugs.....i am lost....

OK, from what I can see on Bikebandits, your carb doesnt have overflow tubing. Here is what I suggest.
1) Remove the carb and check to see that the float isnt stuck. Check to see that once it raises it shuts off teh flow from the feed. You can do this by lightly blowing (by mouth) in the fuel feed tube and then raise the float with your finger till you get the flow of air to stop. I dont have the float height spec but most of the time it is when the float is level in the chamber. You should be able to get a reference horizontal point on the float to determine when the float is level.

2) With the gas coming out of your air intake, equally you probably have a ton of fuel in the cases. Pull your plug and crank the motor over allot without the carb. If you can, tilt the quad on its nose with the spark plug removed. Cycle the piston and see if any fuel comes out the spark plug hole. Yo should get to a point where the transfer ports open and the cases will evacuate. You are trying to get the fuel out and air out the cases.

3) Reassemble the carb. Hook the carb up to the fuel line and while its in your hand and not connected to the intake manifold turn on the fuel and see if it overflows. If it doesnt put it back on the motor and reinstall your plug and try and light her.

[morley8065]

ok, nothing, float isnt stuck, got some fuel out of cylinder when cranked, and i pulled it 30 times and nothing, pulled plug and soaked.....has to be the carb, so might take it somewhere or buy a new carb....i hate it when i cant figure something out.....

[morley8065]

update, just checked compression and got about 70-75....is that way low...or not..thanks

[VAL]

Originally Posted by morley8065

ok, nothing, float isnt stuck, got some fuel out of cylinder when cranked, and i pulled it 30 times and nothing, pulled plug and soaked.....has to be the carb, so might take it somewhere or buy a new carb....i hate it when i cant figure something out.....

Dont buy a new carb right now. Just go through the old one like I said. These things arent that complicated. If you are getting fuel out the spark plug hole without tilting the quad, you need to tilt it on its nose, or at least let it evaporate over a day or two.

Originally Posted by morley8065

update, just checked compression and got about 70-75....is that way low...or not..thanks

This is a 50 cc motor, that sounds alright (not fresh but ok). It was running before the flooding issue.

Get her dried out and the carb set properly.

[morley8065]

thanks, i think the float is messed up, tried to adjust it to specs, but didnt get any fuel in bowl, so dumped a little in carb and got it to puff twice.....thats a start...lol

---------- Post added at 12:04 PM ---------- Previous post was at 10:58 AM ----------

well, she is dead.....had a half of a little washer looing thing come out intake side, pulled it a few more times and locked right up......now, is there somewhere that sells new motors....or should i learn how to rebuild this thing....

[VAL]

Originally Posted by morley8065

thanks, i think the float is messed up, tried to adjust it to specs, but didnt get any fuel in bowl, so dumped a little in carb and got it to puff twice.....thats a start...lol

---------- Post added at 12:04 PM ---------- Previous post was at 10:58 AM ----------

well, she is dead.....had a half of a little washer looing thing come out intake side, pulled it a few more times and locked right up......now, is there somewhere that sells new motors....or should i learn how to rebuild this thing....

Can you post a pic of the "washer thing"?
Rebuilding a two stroke is fairly simple.

[morley8065]

---------- Post added at 02:07 PM ---------- Previous post was at 02:03 PM ----------

i am trying to get piston off right now, i think i am just going to do top end, everything else seems fine, got a little scoring on cylinder walls, not sure what to do about that, can i try to clean it up myself....

[VAL]

If the scoring is super fiscal, that is if you run your finger nail across the area and it doesn’t hang up, you can smooth it out with a scotch bright pad. If its deeper, then it should be honed or bored. (I don’t think these little bikes had their sleeve coated. you should call the shop a find out) If you hone or bore you will need to spec it out to make sure you get the right piston and rings.

I can’t make out what that partial ring is. The pictures are a bit fuzzy. There are three ways for it to have gotten in there. Intake, exhaust spark plug hole or from the crank, piston area. Have you examined these areas to see if there is a source? Need to know where it came from before you spend time and money on rebuilding. The other thing that looks strange to me is the wrist pin hole looks elongated on the last picture. Is it?

[morley8065]

that hole isnt the pin hole, just a hole in the side of the piston, it was also cracked at the bottom....internally it looks good, not sure where the washer thingy came from, but was wedged in the wall of piston pretty good....i think i will try to clean up cylinder wall, slap in new piston and rings and see what happens....

[VAL]

That is the ugliest piston port Ive ever seen. Now that I look at the picture more I see that it is 90 degrees from the wrist pin.

Take a little time and mic our your cylinder to make sure you are where you need to be for your piston.

Wish you the best of luck with the top end.

[morley8065]

thanks, i am trying to figure out if the piston was standard or not, acc. to my manual it should be40.930-40.945mm. i am getting like 41.35- 41.40mm....but they say art, suzuki on the inside....so i dont know if it was already bored out or not..even the cylinder bore seems bigger then my manual...

[morley8065]

well, $133 to bore it out, new piston (1.0mm over) rings, and top end gasket set.....hope this works

[morley8065]

well, she lives...bored anotheer .020 over, new piston, rings, and actually runs....first top end rebuold on a 2 stroke....very easy...thanks for your help....

[VAL]

Good work, congrats