1983 Pw80 Help!

[slowgsxr97]

Hello, im new to the forum but there looks to be alot of knowlege on this site so I decided to join.

I have a 1983 PW80 I just got for my nephew, I put it back together today. I bored it .020 brand new piston, rings, gaskets. My problem is that it just wont run right, it runs very sporadicaly, its revs way up, wont idle. but when i put it in gear it doesnt rev up on its own but still wont idle.

I have cleaned the exhaust it was almost plugged up. cleaned the carborator. But I dont know what to set the screws at. should I check for air leaks?

Also i am premixing the gas but the injector stuff is still hooked up do I need anything special to dissconect it?

any help or advice would be great.

 

[1BAD250]

Are you sure you got the timing right?

 

[TimberPig]

Two things to check, 1) is it sucking air in through the injector system that you aren't using, and thus leaning it out? 2) crankcase seals, you may have a leak.

 

[slowgsxr97]

I checked for air leaks but its hard to tell if it makes a difference when I spray it the way it runs. it it sounds like its running more than half throttle without even touching it.

 

[slowgsxr97]

Ok i sprayed carb cleaner on the oil injector stuff, base and head gaskets and no difference. How can I determine if the crank seals are bad.

With the choke on it revs like crazy. but with it off it wont even idle. {Pilot is clean} i set the floats because gas was coming out of the overflow but it still trickles a little bit.

im stumped....

 

[TimberPig]

Is your oil tank full, or the lines plugged off? It sucks air from the tank through the injector, not from the outside through the injector.

The easiest way to check for air leaks is to vacuum and pressure test the crankcase, which requires plugging the intake and exhaust, and applying pressure and vacuum and seeing if there are leaks. The seals often leak in vacuum, but hold pressure fine. Spraying gas, WD-40 etc on the seals to look for leaks is often used, but is not a particualrly accurate method of finding the leaks, especially when it won't run well enough to idle, like your bike.

 

[slowgsxr97]

Is your oil tank full, or the lines plugged off? It sucks air from the tank through the injector, not from the outside through the injector.
QUOTE]

The oil tank is off, but nothing is plugged as of yet. I put my finger over the 2 holes for the injector and it made no difference.

 

[slowgsxr97]

every thing for the oil injection is properly blocked off. still no change. today it revs like crazy with the choke on but wont idle at all with it off. if I try to rev it with the choke off it will bog untill i let OFF the throttle then revs up. any other tips

 

[JasonJ]

recheck the Pilot jet and pilot air jet passing a single strand of a brake cable or old throttle cable through the hole. This is typical of a clogged PJ as when its on choke it pulls gas up the main jet, choke off, no idle, throttle up and gas starts to enter via the main jet. These little bikes are SO senistive since the jets are so small, I have seen the left over cotton from a Q tip used in cleaning clog the PJ of small scooters. Also, the reed valves can be hung open by even a single blade of grass but that usally causes a no start condition. Recheck your gas mix by mixing up a new batch. Also, the oil injectors on these little bikes are great, consider re installing it as the tiny 2 bangers run rich on oil at idle and are very prone to foul. The injector systems add very little oil at idle and crank up the ratio when the throttle opens up. Very nice, I dont know why people hate them so much.
JG

 

[slowgsxr97]

It was dissconected when I bought it, I dont want to chance hooking it up if not functioning properly. the pilet jet looks clean and I can see through it but I cant even stick a sewing needle through it long ways. is the hole really that small?

 

[JasonJ]

yes it is. Thats why I say pull a single strand of brake cable off about 6 inches long, and push it through there. You can then spin the jet on the wire to clear it out. Check the rest of the PJ passage as well and use that cable strand to work your way through the air passages. The cable strand is flexible and strong enough to work its way through even 90 degree bends with some spinning and pressure.

 

[slowgsxr97]

new seals installed

 

[slowgsxr97]

Bike is together and ripping around the yard, crank seals it was! thanks everybody