Kubato ZG222

Thumprr

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I have a ZG222 for about 8 years now. I have really enjoyed it. Recently, on two different occasions I have got gas in my oil? I changed the oil and filter, all is well again. Several weeks later the same thing happened again? Anyone ever had this problem before?
 

bertsmobile1

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About 20% of the posts here are because the needle valve in the carb has failed to close off fully allowing fuel to overfill the carb & dribble down into the engine.
So remove the carb & clean it check the flaot valve i making a seal by inveting the carb & blowing through it.
In good condition the float needle will resists 10 psi from the weight of the upside down float alone.
 

Rivets

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lugbolt

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Excessive idling can cause it too. So can evap system problem.
 

StarTech

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About 20% of the posts here are because the needle valve in the carb has failed to close off fully allowing fuel to overfill the carb & dribble down into the engine.
So remove the carb & clean it check the flaot valve i making a seal by inveting the carb & blowing through it.
In good condition the float needle will resists 10 psi from the weight of the upside down float alone.
And this should be done using a pressure gauge to check for slow leakage as needles and seats do develop fine line leaks that would pass a quick none gauged test. I usually test that they hold the same pressure for at least 10 minutes.
 

johnorlandi

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I have a ZG222 for about 8 years now. I have really enjoyed it. Recently, on two different occasions I have got gas in my oil? I changed the oil and filter, all is well again. Several weeks later the same thing happened again? Anyone ever had this problem before?
I have a B4200 2 cylinder and had the same problems I spoke to the dealer and they had me change the diaphragm in the fuel pump and this stopped the fuel from getting into the oil hope this helps
 

lugbolt

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I have a B4200 2 cylinder and had the same problems I spoke to the dealer and they had me change the diaphragm in the fuel pump and this stopped the fuel from getting into the oil hope this helps

well a ZG222 has a competely different design, it is a completely different machine altogether and honestly has no place in this discussion because there is literally no similarity whatsoever.

Wait, it does have some similarity. They're both Orange. Sorry.
 

Born2Mow

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About 20% of the posts here are because the needle valve in the carb has failed to close off fully allowing fuel to overfill the carb & dribble down into the engine.
First:
You did the correct thing by changing the oil and filter. You'll need to do that every time this happens.

Second:
The float valve in the carb was always an "iffy" setup. The problem is that GRAVITY is always going to put fuel pressure on the valve, and the float valves aren't perfect.

The TRUE solution is to add a manual fuel ON/OFF valve to the system. And then start using it with the ZEAL of a new religious convert. Many newer fuel systems have an electrical fuel cutoff valve, but those can't be diagnosed.... until it's too late. IOW, they are untrustworthy.

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The manual fuel valves, which every store sells for $5 -$8, is the only safe, fool-proof solution. The only other solution is to run the mower completely out of fuel after every use. This because GRAVITY is working against you 24/7/365.
 
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lugbolt

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ZG222 already has a shutoff valve.

Behind R.R. tire buried back there. It also has a drain function built the valve so you can drain the bowl.

On the 222 and 227 both (same engine) the carb sits down in the engine valley. When you turn the engine off, it gets hotter. The heat radiated from the cylinder heads has been known to cause fuel boiling. Could potentially lead to fueling of the crankcase. It'd be odd. Typically the boiling issue results in no or hard starting when hot, have to let it cool in order for it to start. This condition is most often found with guys who use a small enclosed area to store their mower after use, i.e. enclosed trailer, small shed, etc.

Also if the float valve sticks it just normally fills up the intake manifold. The bowl doesn't hold much fuel. The tank is lower than the bowl, so it doesn't gravity feed (hence the need for an electric fuel pump behind the seat). Generally when the 222/227 float vavle leaks, it causes hard starting (flooded hard starting) when cold, before its' been used for the day. Only seen one that filled the engine, and it was on a mower that was stored in a shed that set on a hillside, such that the fuel would actually flow into the left cylinder's intake port. Weird one.

I still think that the evap system can be an issue with filling a crankcase on a 222 that is newer than about 2014. It's got a check valve and a pressure relief that is supposed to relieve tank pressure so that the fuel pressure doesn't rise so much to cause the tank to swell and hit the tire and enough to overcome the float valve. I've seen a stuck relief cause the tank to hit the tire, and owner will keep using it not knowing and next thing you know the tire eats a hole in the tank and creates big leak, but haven't seen a float valve leak because of it yet. "Yet".

Excessive idling WILL cause fuel vapors to build in the crankcase over time. Perfectly normal. Engine isn't designed to idle a lot. Full throttle/speed is what it's designed for.
 
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