Yamaha G9 stopped running this weekend at camp

[maxim1157]

Hey guys.. got a question about my buddies G9. It quite on him Sunday morning, he said it was running very poorly and spit and spuddered getting it back to his lot. I took off the gas line to see if the pump was getting fuel up to the carburetor.. it was okay there. I pulled the plug next and it was black and wet with fuel, tried cleaning the plug and was checking to see if it had spark.. very little spark. I pulled my plug out of my cart to see if it would fire up his cart.. same exact plug, but it too would not fire his cart.. I'm wondering if the coil is bad since the spark was not very strong??

[spriddle]

More than likely it needs a good tune up if you're getting a spark. NGK plugs foul really easy and are usually not very good after they foul out. It's probably dumping too much fuel since you swapped the plug with yours and same issue (your plug could possibly be weak also or fuel pump is full of grit). Pull the oil dip stick and see if it smells like gas down in the crankcase mixed with oil.

I'd start with new plug, pull bowl on carb. and clean the entire carb out best you can with carb cleaner, pull the fuel pump, take it apart and clean it. Check the fuel filter in the bottom of the tank also (I suggest removing it and installing an in line fuel filter, you'll have to cut the filter part out more than likely). Take out air filter and blow it out really well and make sure it isn't covered with oil or fuel (if so, post back). The air box should be completely sealed. Check the little hose going to the back of the engine that helps pump fuel. If you pull the carb., be very very careful with the spacer, simply snug the two 10mm nuts only. It can crack very easily!!

And I know this may sound crazy, but pull the battery cables and clean them and the battery terminals really well. G9's are notorious for not running well with corroded battery terminals.

Also make sure the muffler is not stopped up somewhat. Just something extra to check on these after a good tune up. If it is, check out our thread on muffler BBQ: http://www.buggiesgonewild.com/gas-y...-hot-pics.html

I always start with the least expensive items first and work my way up. Probably needs a good tune up anyway.

[maxim1157]

I had his cart home 2 yrs ago because it wouldn't run, and took everything apart and cleaned it. Removed the filter in the tank and went with an inline filter then. Took carb to work and used our ultrasound cleaner got it good and clean.. didn't look at airbox or check the crankcase, but it was pumping out fuel when I had the plug out. I just didn't like the weak spark I was seeing.

[CP241]

If the spark is weak, check the grounds and check the coil and spark plug cap. The cap is available separate from the coil and should read ~5k ohms.