2008 150cc Lance Won't start or idle By andre150 (Read 715 times)

[andre150]

Hi all, I have a 2008 Lance scoot that ran ok about four years ago before storage. I've been trying to get it running after following most of the tech items I know. 1) CARB pulled the carb, cleaned the jets, blew out all the orifices, and checked the idle screw, etc. 2) cleaned out the tank and manually tested the vacuum petcock (works fine under vacuum), 3) changed the plug 4) checked the valves and lash (.04 and .05), 5) replaced the vacuum lines from manifold to petcock and top of carb 6) checked to see if run kill switch was working (bypassed and wired directly) 7) checked manifold for leaks 8) changed out gas and added seafoam 9) test to see if spark (good spark), and finally, moment of truth, used a bit of starter fluid and got the engine running, but only as long as the ether lasted it wouldn't run longer than a few minutes.  So, I took off the carb, cleaned the jets again, opened up the idle screw a bit more (one more turn, so two complete turns total) and bent the floats tab down a bit to let more gas into the bowl.  Back to using starter, and now the engine only runs until the ether runs out .. about 5 seconds, worse than when i started.  So, took carb off, moved the float tab up a bit, and tried again.  No luck. Then turned idle screw back in a turn, no luck either.  I've given up on using starter fluid, as that's not actually getting things going.

I did notice when doing the valves that with the plug in, it was pretty easy to turn the engine through the compression stroke, so maybe poor compression? But it does run with starter fluid.

I'm about at the limits of my engine knowlege, so maybe some tips/pointers.  I did notice a hose missing off the EGR, but that wouldn't keep the engine from running would it? just poorly.

[andre150]

Ok, found the loose wire in the auto choke! and it starts, but only with starting fluid, and runs for about a minute or so, but only at full throttle -- as I hold the throttle steady, the engine just hunts for a steady consistent state.. backing off the throttle down or to the idle stop and the engine dies.  I can restart it occasionally right after, but it will only run at full throttle, but doesn't sound wide open, rather hunting and bogging down..  then it dies after about a minute (fuel starvation?? .. looking at the inline filter, and i see gas in the filter.  After dying, but letting it sit for a few minutes and it won't restart without starting fluid.

Sprayed starter fluid around the carb/intake manifold connection and the engine sped up. So, there's a leak in the intake manifold.

Thought it might be the pilot jet as well, without starter fluid near the intake or airbox, it dies, pulled the carb again and made sure the pilot was cleaned out.

[kz1000st]

Replace the intake manifold. They dry out and crack over time letting the engine run lean.