80 liquifire won't stop running!

[deereoftheyear]

I took my liquifire out last week end. Ran good but when I went to shut it off it would sputter and keep running. Turn the kill or key on runs great again. Flip the kill switch or key again, sputter but runs. I made a wire jumper across the key contact still runs and sputter but won't shut off. Remove wire runs great. Any ideas? BTW I have basically replaced or rebuilt every part of this sled over the last 3 years...except the igition. CDI? Rev-limiter?

Thanks, Luke

[robtan88]

Luke. With the spark grounded out, the only concievable thing that I can think of that would cause this scenario is extremely hot combustion chambers still igniteing the fuel such as hot glowing carbon deposits, or your engine could very well be running lean and ready to burn down on you. I would take a very good hard close look at this. Just my opinion, and hope this helps answer your question...Rob.

[427cobra]

Try turning the ignition off or hitting the kill switch. Then pull it over a few times...do you have spark?? If there is still spark you probably have a bad ground or bad connection. If there is no spark then your engine is dieseling as described above.

[lwb140]

i have an 80 sportfire that my daughter dearly loves , she rode it last winter putting arounf the yard at this time she was 8 years old , it had a rod bearing bad and you could hear it knocking and banging as she rode it but the damamge was already done and seemed to not to be an issue until she went to shut it off . we pulled the plug wired off the plugs and it continued to run , we ended up choking to death , seem like that was the last time she rode that sled that year

[JoeRainville]

Luke,

After I overheated my Liquifire in the I-500 last year, I pulled the teather to kill it. She kept running. So I hit the kill switch. She kept running. I choked it and started to open the hood to put my foot on the clutch, and she finally died. Ignition system was fine, she got so hot it was "dieseling" or running on 'pre-ignition'. I have heard of a Liquifire running away RPM wise doing that.

Either she is getting too hot, or too lean, and getting a hot spot on the edge of the piston, ring or spark plug. It's causing the air/fuel mixture to start to burn when it hits that hot spot. I am guessing your plugs are not goopy black, but white, showing a lean condition. This can be cause by leaky seals, dirty carbs, or too much igniton advance.

I hope this helps,
-Joe Rainville

[deereoftheyear]

Im going to run it again tonight or tomorrow. Im going to check the plugs too. I pretty confident on crank seals as I replaced them last year. Ill keep you posted.

Thanks, Luke

[deereoftheyear]

UPDATE

I took the sled out today a little. With the kill on and the engine running rough I opened the hood to pull the plug wires off to check if was deiseling. Engine imediately died when I opened the hood. Found wires at hood hinge shorted whenever hood was shut. Repaired, OK