Kubota TG1860G Gas Starved

[com.one]

I have a Kubota TG1860G. It starts right up and runs absolutley perfectly for about 20 - 30 minutes. Then it starts spittin and sputterin like it's starved for gas. I let it cool down and it runs perfect again,,,, for about 20 - 30 minutes. Then the procsess starts all over again.. I blew out all the fuel lines and cleaned the gas tank out but that didn't change a thing. I love this machine, I just can't seem to figure out what is getting hot that makes it starved for fuel and start missing.. Any ideas

Thanks A Million
Jeff
com.one

 

[John C]

I am unfamiliar with your model but for the sake of this post I'm assuming that it's a gasoline engine! If thats the case and it's carburated what you discribe is commonly known as vapor lock. this happens when the gasoline in the fuel line becomes hot enough to boil to a vapor and due to the pressure created within the fuel line at the point where this is happening carb starves for gas. Years ago I had several old carbed engines that did this it's usually fairly easy to fix by rerouting fuel lines away from heat sources. I had one that clipping wooden clothes pins onto the fuel line across the top of the engine created enough of a heat sink that it cured the problem without rerouting the line. once again this is assuming that your talking about a gasoline engine!

 

[com.one]

Yes,,, It is a gas engine. And I will sure follow the gas line to see if I can see where it's laying against anything hot.. Thanks a million for your response I really appreciate it..
Jeff

 

[Ob1kubota]

I have a Kubota TG1860G. It starts right up and runs absolutley perfectly for about 20 - 30 minutes. Then it starts spittin and sputterin like it's starved for gas. I let it cool down and it runs perfect again,,,, for about 20 - 30 minutes. Then the procsess starts all over again.. I blew out all the fuel lines and cleaned the gas tank out but that didn't change a thing. I love this machine, I just can't seem to figure out what is getting hot that makes it starved for fuel and start missing.. Any ideas

Thanks A Million
Jeff
com.one

I'd like for you to also look at the vent in your fuel cap and make sure its breathing as designed. Quick check is to run the tractor until it starts acting up and at that point loosen the cap up and see if it clears up.

 

[Michael]

If it is fuel starved because of a vapor lock the trick that I have used in the past is several big washers with a small center hole. I avoid using cloths pins but only for a short term fix as I have seen them almost catch on fire anytime they are near the exhaust manifold.

The trick is to take the line loose and then get a washer that has a small inner diameter that is close to outer diameter of the gas line and little RTV. I simply remove the line from one end and slide the washer down to where the line sags against the engine and then I use a dab of the RTV (high temperature RTV) and then I use another washer a little ways up the line until it clears the part that is sagging against the engine. I used this trick was I was living in Texas and Nevada where high temperatures and low humidity tended to cause problems for any gas or diesel engined vehicles. The reason I used the RTV was to prevent the washer from moving and having the washer abrade the line.

I had a old Plymouth Duster with a slant six engine that was really prone to vapor lock and once I did the washer trick it never vapor locked on me again and I had the car for 15 years.

 

[Ob1kubota]

I have a Kubota TG1860G. It starts right up and runs absolutley perfectly for about 20 - 30 minutes. Then it starts spittin and sputterin like it's starved for gas. I let it cool down and it runs perfect again,,,, for about 20 - 30 minutes. Then the procsess starts all over again.. I blew out all the fuel lines and cleaned the gas tank out but that didn't change a thing. I love this machine, I just can't seem to figure out what is getting hot that makes it starved for fuel and start missing.. Any ideas

Thanks A Million
Jeff
com.one

Jeff here's another idea... if it happens with time and heat if you observe your fuel filter ( assuming its clear ) see if its half full on the suction side and if full I would then put an inductive type spark indicator on the plug wire and watch the LED indicator to see if it's erratic. If erratic ( in other words it hits and misses like the engine rpm) I would suspect the solid state CD ignition module as breaking down dielectrically from heat, This would explain letting it cool down and then starting normal and running until it breaks down again. It's worth a try... advice is cheap, frustration is expensive. That TG1860 is a great mower, wish I still had mine. I traded for a new GR2110 so far, so good with the hydrostratic transmission...