Kubota RTV900

[chado613]

Occasionally when starting the (diesel)kubota, It will start and rev extremely high right away and shut itself off when cold. It will then have to sit for a bit then will usually start right up.

I replaced the fuel filter on the weekend and I went out to start it up this morning, the following happened:
1. Glow the plugs for 25 seconds
2. Started it up
3. Began revving higher and higher
4. Tons of dark grey smoke was coming out of the exhaust
5. I turned the key to the off position
6. The engine kept running hard even with the key off
7. eventually after 20-30 seconds it began to rev down and shut it self off

This only happens when starting the machine cold, It does have a block heater and if plugged it starts fine. Last winter though the machine never did this. I am worried this will lead to a future (larger) problem(s).

I am not sure what the heck is going on here and if anyone has had previous experience with something like this I would love to hear from them

 

[JOHNTHOMAS]

I laid a diesel powered tractor on it's side and it did this high revving and smoke just boiled out. Started fine and ran fine after I got it back on its wheels.
Have an RTV1140 with no issues until it got -15 and I hadn't put Power Service white bottle in it and it would start, run and then die. I added Power Service and waited awhile and it started and has ran fine since. Will do Power Service silver bottle in summer and Power Service white bottle in winter from now on. Have added Power Service white bottle for years year round and had quit doing it this past summer.
Post cure for your RTV when you find out the problem. It's getting excess fuel at cold start up for some reason )if it isn't laying on its side like my tractor was).

 

[Kanook]

How's your air filter look...Sounds like an excess of fuel...The solinoid should cut the flow of fuel when you turn the key off...Others on this forum have experience/knowledge in regards to 'diesel runaway' that will likely jump in.

 

[Gary Fowler]

That sounds like a governor problem, but I have no idea how to fix or what is causing it.

 

[chado613]

I talked to the Kubota dealership in my area and they mentioned that they have seen a few cases where water(ice) has gotten into the injector pump. So as JOHNTHOMAS mentioned I got some power service white. I also got the red which is the diesel 9-1-1. I am going to try this and I will share the results. If this doesnt work I guess the next step is removing the pump to get the water out. Does anyone know if that is a big job?

 

[lakeridge]

Your problem is related to condensation and moisture around the injection pump not moisture in the fuel. The governor linkage is freezing due to this moisture resulting in the fuel rack lockup at startup. The governor linkage is lubricated by the engine oil. You have moisture in the oil around the engine pump cavity of the block. You need to get that moisture out of the area.

 

[chado613]

Lakeridge Sorry if im being dumb here but I am relatively a inexperienced in the mechanical field, but would an oil change help fix this issue?

 

[kuboman]

I betting that the kind of use your rtv gets is a lot of short runs? You need to take it out and run it hard so everything gets good and warm so the moisture will evaporate out. And yes an oil change will help after you get it really warmed up.

 

[chado613]

Kuboman you are correct, its used to to collect the manure from the horse stalls then a short run 200 feet away to dump it.

Thanks for all the help guys I am going to try these suggestions and let you all know the results

 

[RollingsFarms]

The red bottle Power Service is for gelling diesel, there's another white bottle that they make that deals with water in the fuel. It has some green writing on the bottle so that's how you distinguish that one from the other white bottle they sell. I have never used the red bottle but I regularly use both white bottles and the silver bottle.