ATV Question AGAIN

I did post a ATV won't start topic earlier and received some comments to help me to fix it, clean the Carb, 91 fuel, replace the coil, CDI ....... it works. but the ice wasn't good enough for it, it stay in the garage for 3 weeks after fixed. then last Monday I try to make it ready for Saturday, but it won't start again, I can hear it crank but hard to start, then I try to press in the throttle then push the start button, I heard pop pop pop from the Carb intake, I took the connect hose between the air box and the carb, when ever it crank, fuel is come out from the carb intake, then I press in the throttle then push the start button, sometimes it will fire and pop pop pop pop then die, Finally, I change a new choke today and Spray Quick Start in the intake, seems it will pop a bit more, after a few times. it start again, after it warms up, I quickly spray seafoam from the intake a few times until it runs smoothly, after that I noticed there was lots of water splash out from the Exhaust Pipe. it's black in color. The ATV is sitting in the middle of the garage, I can tell the water splash is very strong cause I found the water was on the wall too. it seems all the water was being push out when it start. Is that mean I have too much water in the engine or Exhaust before. How and why? I am going to change the oil maybe 2 times, try to flush the engine to get all the water out. Beside this what things can I do to avoid this happen again.

Any thoughts and idea is appreciated

Sounds like a jetting problem with you're carburetor.

But I did clean the carb from top to bottom twice. 100% sure it is good.

But I did clean the carb from top to bottom twice. 100% sure it is good.

It may be clean but has it been adjusted/set up? I would recommend you start by getting it set up properly and then go from there.

I wouldn't worry too much about the black water coming out the tail pipe, both of mine will do this when I start them up in the winter after they have been sitting awhile.

Do you keep your battery on a trickle charge when you are not using your quad? This would help give you better cranking amps when starting.

first don't use starting fluid, a little water from exhaust is ok but if its lots check antifreeze coolant level if its going down may have gasket gone, possible poping out of carb could be valves need adjusting intake could be sticking open not allowing fuel and air to compress well and if its stuck open allows fuel to ignite in carb causing popping sound. if you did carb make sure float level is ok and settings are in proper place. even do a compression test do a dry and wet test let us know what you find

After I clean the Carb, I reset everything as per the service manual. I did clean the carb before. I have the battery connect to a trickle charger like my bike during winter season. I understand small amount of water will come out from the pipe, but this time is different, it's a BIG splash, I can tell by the water mark is 7 ft far. I did think of the valves problem too, I was planning to adjust the valve, but after it start I talk to my son and his friend, his friend is a mechanic, he said looks like somewhere in the exhaust is chocked by condensation and carbon , I was lucky all being blow out suddenly. If not, it will takes a long time to find out.

By reading I would be suspicious of the needle and seat not sealing. Does the black water smell like gas? If the carb is flooding and letting gas straight through it will end up in the crankcase and mix with and thin out the oil to a water consistency. Will also ac ount for slow cranking since the crankcase level will be much higher causing more fluid resistance to the crank shaft and eventually hydro locking the motor. I would check the oil level and smell it to make sure it's not super high and gassy smelling.

Yeah, I was thinking like this too but the oil is fine, just dirty, actually the fuel pump will stop working if there is no spark. So, chance to flooding the carb is very low. I did check the black water too. Can't smell and gas in it and it's just black dirty water.

Change the slow jet in the carburetor its a #38 you can use up to 45 I think but go with a #38 it's a eight dollar part it should fire up.

I noticed you mentioned you have a service manual. If so, measure your valve travel. A popping sound out of the intake indicates a worn exhaust cam lobe. Just a few thousands of an inch will do this.

From the symptoms you mentioned, that's where I'd start. If the sound is more like a backfire, you have an ignition problem.

Forget the water in the exhaust. It's simply a build up of humidity in your exhaust because the engine isn't breathing properly. Once you have it running right, the water will dissipate.

Thanks, it start and run like before, but I still want to adjust the valves and check the timing chain, the first thing is take out the Cap cover, it's a screw in the middle of the left crank case, It stuck like rock, I think I need to destroy that screw, if I can't take it out, then I can't get to the TDC and find out where is the "T" mark inside the crankcase, I can't do the rest at all. Since it start and run, I am going to use it for the rest of this ice season and make it as my 2017 Spring project.