My kid's LT 80 will start just fine and idle great, but when you punch the gas it falls on its face and wants to die. Any idea's what to look for? I have replaced the o-rings behind & infront of the carb mount plate. This is a 1990 LT 80. Any help would be great and save me from selling the Suzuki and looking for another atv!

 

Sell the quad when a simple carb cleaning is needed?
You have something blocking your main jet. [img]i/expressions/face-icon-small-smile.gif[/img]

 

Thanks, I'll clean the carb. They are out growing it anyway, it's easier to sell if it's running right! Thanks for the help.

 

Took the carb all apart and cleaned everything. Put back together and still have the same problem. Any other ideas why it idle's great but won't go when you hit the gas?

 

Yep, you have the same problem I did.

Remove the gas line from the pet-****, open it and see if gas flows, if it doesn't like mine it's clogged. Also check the diafram for the fuel return, they go bad over time. Also when it starts to fall on it's face, put the choke on it should "run" better but won't idle very well now, thats how I narrowed it down to a fuel delivery problem.

Good Luck and hope you don't run into the same problem I have, can't get the screws off for the pet-****, the metal inserts in the plastic tank are spinning. Still looking for a solution to that (see other post)

If you get yours off, take a look for me and see if there is any way to keep it from spinning if I cut the heads of the screws off. Thanks and again Good Luck.

 

You removed both jets and cleaned?
OK, check the petcock (like eatseregg suggested). Put the petcock on prime and see if fuel flows. In the on position, it will not flow till vacumm is made.
Fuel return?? That's a new one.I'm thinking he may have meant the vacumm line!?
Reed,compression,plugged pipe is where we will look when you eliminate the fuel flow question.

 

It's not the fuel flow, done checked that. Also when It's at idle and I put the choke on it runs worse or dies. Motor has been bored and new piston about a year ago, ran great. Will a bad reed let it idle but not run right? Thanks for all the help on this.
Tony

 

Guess thats what it is sorry miss quoted on the vacuum line thing.

I didn't check it cuz found the fuel problem but a friend did suggest a cracked reed might cause the same condition. I'm a 4-stroke guy so I'm kinda at a loss diagnosing these 2-strokes LOL [img]i/expressions/face-icon-small-blush.gif[/img]

Good Luck

 

I thought I found it but NOT. Getting closer, still need help. I removed the rubber air duct from the carb to the breather and the atv runs like it is suppose to. I took apart the breather box and it looked pretty choked up. (Thought I had it) After cleaning everything spotless and reinstalling, I still have the same problem. I removed the beather duct from the carb to the breather again and it runs fine again. Why don't it run with the breather hooked up????
Thanks Again for the help so far!
Tony

 

Finally found the problem! It ended up being the small vent line running from right side of the carburator that runs up by the seat. It was totally plugged. Once I blew it out the LT 80 is back to itself again! Thanks for all the help on this. Hopefully if someone else runs into this problem this thread may help cut down some time.
Tony