Kubota flooded

[Jason Morgan]

A man that I am working for just bought a Kubota 4700 from the auction. It has a five cyl diesel. We hooked a brush hog up to it today to test it out. Opened the throttle started to mow and not 45 seconds later, I heard the belt squeal and she started blowing white smoke. Didn't miss though. I idled her down, noise went away, still heavy white smoke. shut motor off immediately.Determined it was raw fuel being dumped into the engine. Tried to restart revved up blew white and died now will not start. Motor flooded with diesel. I am guessing the injector pump is wasted. Any ideas or suggestions would be greatly appreciated because I would like to help him fix it. Thanks, Jason.

 

[RodinNS]

Not familiar with the tractor... Does it have an inline pump or a rotary pump? Is there an external lift pump somewhere else on the engine?
I thought most of the Jap stuff used inline Kiki pumps... and those dumping fuel into the engine would be unusual. A rotary pump... not so unusual as the drive shaft seal can fail and then it lets fuel into the engine.

Other thoughts are bad injector(s) and bad glow plugs. Would it not start hot or just cold? Could be several things going on.
The white smoke I would generally attribute to a bad injector or low compression but one bad injector doesn't keep a 5 holer from starting.
Also... check the coolant. Could be a bad head gasket...

Rod

 

[504]

White smoke is water/anti freeze. Motor is water locked.

 

[David G]

I would also think it is antifreeze, diesel should be black smoke. It may be hydro locked if it does not turn over. Check compression on the cylinders. You may have blown a head gasket, if you are lucky.

 

[RodinNS]

White smoke indicates a cold fire wether it's in a cylinder, a furnace or a brush pile. In this case the cold fire could be from water... or it could be from a bad injector that's spraying a big shot of unatomized fuel in there...
Black smoke suggests a moderately hot fire with more fuel than oxygen available to burn it...

Rod

 

[Jim in Ma.]

Could someone have put gas in it insted of fuel??

 

[KSTractor]

Most Kubota engines have a compression release, look for linkage on the valve cover make sure it is not holding the valves open not all models had a cable to work it from the dash. It should never be used to stop the engine, only to get the engine spinning to start it, helps when the battery is low.

 

[Jason Morgan]

It does have an inline pump. I have pretty much already determined that it is large amounts of raw diesel being dumped into the engine causing the white smoke. When i smelled the smoke it smells like diesel and I don't smell antifreeze. But the diesel fuel that is in it smells old and stale. I wonder if bad diesel fuel could cause this? I probably should have mentioned, that when the smoke started to bellow out it was more dark grey and then dissipated into white.

 

[Jason Morgan]

The motor turns over fine, but I am not smelling any antifreeze in the white smoke coming out. the diesel fuel does kinda seem not normal. It smells old and stale.Seems a little oily or slimy on your fingers. Something just dosent seem right about the diesel thats in it. Coming from the auction there is no telling the story on it, may have been sitting awhile.

 

[Jason Morgan]

Thanks, I will look for that. If that compression release is cracked open the slightest that would explain why the fuel is not ignighting. Because even when cranking it puffs a little of the white smoke.

 

[Jason Morgan]

I will double check that. But I am kinda with Rod on this, I think its a cold fire. I am not smelling antifreeze and the radiator full. I hope somebody didn't put a band aid on tis tractor to get it though the auction. Ya never know.

 

[Jason Morgan]

No not suspicious of that. But the diesel does seem kinda old. It kinda smells like someone put kerosene in it.

 

[David G]

I would modify my claim of antifreeze and agree it could be a non ignition problem. The compression release could be an issue. The tractor would appear to be flooded.

 

[Jason Morgan]

Pulled the manifold today and determined cyls 123 were wet. Injectors looked good gonna have them tested and go from there.

 

[Tramway Guy]

Also check the air intake system. If it is blocked you can get symptoms like that...