View Full Version : 1988 LT80 Questions

08-25-2007, 12:17 AM
I recently picked up a 1988 LT80 for my daughter this week. It had been sitting for several years and I just got it running tonight. I have been reading the posts on the forum and have a few questions.

1. Oil Injection
I am curious about the oil injection. The quad smokes sometimes, but it is not consistent. I briefly removed the output line of the injector pump while it was running and it was not "squirting out" like I expected. How much oil should come out of the injector pump under normal conditions. The lines are clear and I have cleaned the carb thouroughly. Air can flow freely through the output tube through the injector orifice inside the carb.

2. Idle
The quad does not idle well at low RPMs . I did a compression test and it has 100 psi. I have disassembled the carb and cleaned it thouroughly. I do not have a manual yet, but there is one adjustment screw on the carb that appears to be for idle speed. If I decrease the idle speed until the quad stops "pulling" then it dies after 10 seconds or so.

3. Lubrication
Is there somewhere to check the lube level in the engine / transmission. If so, what type does it use? This is my first 2 stroke so please excuse my ignorance. The only place I saw to lube the quad was a grease fitting on the rear of the axle housing. I am going to get a manual, but my daughter is really "chomping at the bit" to ride. I just don't want to damage it because of the basics.

Thanks in advance for your help...

08-25-2007, 11:41 AM
Welcome LT80 newbie. :)

The oil injection: there should be opil drip out, it is slow. Removing the oil inj. and running pre mix is the best.

Yes the screw is the idle adj. It should idle fine but after sitting, it may need some running to get the old gas and such out.
100 isn't the best but should be good enough for now. I've seen alot worse and run.

And you did remove the pilot jet and make sure the lil holes were clean
You also cleaned the gas tank out.
You also tried it with the petcok on prime to see if the petcock/vaccum isn't the problem. <G>

Pulling at idle may point to a clutch problem. I'd maintenence the clutchs while you have the clutch cover off disabiling the injector. LOL
You'll be checking the rollers for flat spots,hard grease,wore variator (where the rollers sit).

That'll keep ya busy. :D

08-25-2007, 02:56 PM
Thanks for the speedy reply LT80. My daughter and I went trail riding today and after running for a little while, it started idling alot better. I noticed that it is really hard to start when cold. To get it to crank, I had to shoot a little starting fluid in the intake. There is a small gap in front under the tank that worked great for that. It starts great when it is warm. I did clean the pilot jet, tank, and petcock on prime. New inline fuel filter too. Lots of fuel flow on prime.

The oil injection seemed to work great all day. She was smoking normally the whole time. I still may remove it and mix though. I'm not sure how much I trust it.

I think I do need to look at the clutch as you suggested. I don't know how much torque it is supposed to have, but I feel like it should pull up a small hill from a stop. It just sits there. I let her try because I am 190# but it did the same with her. She weighs about 65#. It runs really fast when you can wind it out though. All in all, we had a great day.

Also, does the crankcase or transmission have any oil in it? I cannot find anywhere to check it.

Thanks again!

08-26-2007, 07:50 AM
LOL, I forgot about the oil. :)

In front of the front sprocket, there is a 6mm bolt (10mm socket).
You remove that and oil should drip out. If not oil is needed. 10-40 works fine.
Above the sprocket on the top of the motor there is a bolt to put fluid in (12mm socket).
If you widh to drain and install all new oil, on the bottom is another bolt like on top.
Glad to see it comming around. :)