kubota 4701 engine problem

[dan210210]

i started my tractor last sunday...it was cold about zero..i let it warm up..went into the barn to check on a calf..when i came out..the tractor was racing above 3000 rpms..and blowing white smoke..out the exhaust..i turned the key off it wouldnt stop..when i finally got it to shut off...it wouldnt start again...its a 2016 with 600 hours on it..i think it broke a ring

 

[plastikosmd]

How did u get it to shut down?
Was this a “run away” situation?

had that happen on a dirtbike once
I even pulled the plug wire off to no avail
I thank god the clutch held and I was able to flood it with choke
No way I could get to a co2 extinguisher or operate it!

 

[Jerry/MT]

i started my tractor last sunday...it was cold about zero..i let it warm up..went into the barn to check on a calf..when i came out..the tractor was racing above 3000 rpms..and blowing white smoke..out the exhaust..i turned the key off it wouldnt stop..when i finally got it to shut off...it wouldnt start again...its a 2016 with 600 hours on it..i think it broke a ring

Sounds like the governor failed.

 

[Dave M7040]

Start asking dealer and Kubota headquarters about Kubota programs in some areas for crank case vent system heaters.

A known problem for some models in cold areas. Some models require an alternator upgrade to handle the heaters used to keep the positive crankcase vent system from freezing tight and then forcing crank case oil into the cylinders. If you have a turbo, the crankcase oil can be foreced up the turbo drain. The engine can run on warm crankcase oil.
This is a post from a Kubota owner:

"Kubota has determined that a defect which relates to cold weather operation exists in certain tractors and may cause internal engine damage if not corrected. "

Kubota has indicated that this issue was known internally in April 2016.

I purchased the tractor in November 2016.

The sent out the product improvement campaign to dealers in December 2016.

They sent me this email notification November 2017 after almost a year of cold weather use.

Further responses from Kubota indicated:

"In freezing temperatures there is a possibility that moisture buildup in the closed crankcase ventilation (CCV) filter could freeze and restrict air movement. If this occurs the engine crankcase pressure can build and spray oil out of the dipstick hole. To prevent freezing from occurring a heater kit has been developed. "


Dave M7040

 

[JWR]

Not sure what you had happen but it is NOT sucking crankcase oil and burning it through the PCV route. I had that happen one time driving a VW diesel. Ring blowby in a worn engine got so bad it put enough pressure into the crankcase to force crankcase oil back up into the intake. The rear view mirror was the biggest black cloud of smoke ever seen on a US highway! If you have white smoke it certainly is not burning crankcase oil.

Since diesels do not involve electrical ignition, it would have gone until it burned up the engine. No way to cut it off. I was able to shift into high gear and overcome the engine with brakes until I finally stalled it out.

Being this far into telling the story you need to hear the rest. I used a Metamucil jug (plastic container maybe quart sized) and plumbed the PCV hose into a hole cut into the side of the jug with the outlet from the top of the jug back into the engine. This caused the Metamucil jug to gather oil by gravity keeping it in the jug over a week or two when I would then pour the collection back into the crankcase and go ahead. Hard to believe I did that & even harder to believe the person I sold it to listened to the story, said she understood, and got in to drive it 1500 miles to Denver. True story.

 

[Agvg]

i started my tractor last sunday...it was cold about zero..i let it warm up..went into the barn to check on a calf..when i came out..the tractor was racing above 3000 rpms..and blowing white smoke..out the exhaust..i turned the key off it wouldnt stop..when i finally got it to shut off...it wouldnt start again...its a 2016 with 600 hours on it..i think it broke a ring

How advanced injection system is it on this engine?

 

[5030]

So you installed a 'catch can'. Good idea. Have them on the cars. I dump the 'slobber out however.