Kubota ZD25F No Start

MarineScott · May 2, 2010

:confused2::confused2:I am working on a Kubota zero turn mower ZD25F. The soleniod for the starter was bad, replaced the starter and I have a cranking but no start. Filled, charged and load tested the battery-Good. Changed fuel filters, Drained and re-filled fuel. Checked for voltage at the glow plugs, ohm checked the glow plugs,all seems good, still no start. I was told the battery might not have enough power to turn the engine fast enough....true?????
I work on cars on a daily basis as my occupation and I am mechanically inclined.I do not own this Kubota. This is my elderly neighbor who lets me use anyone of his 3 Kubotas as I need. Any advice will be appreciated.
Thanks Scott:confused2::confused2:

Jim Thompson · May 2, 2010

Sounds like a fuel problem. Loosen one of your fuel lines at an injector and spin the eng. It should have fuel present. If not, Check the fuel shut-off solenoid, possibly the fuse or a connection.

Also, if you changed the fuel filter, there are specific bleeding procedures. Normally you bleed the line to the injector pump. Then, since you've spun the engine, you'll have to bleed each injector until there is no air in the lines and it should run.

milkman · May 3, 2010

Check fuel shut off solenoid, I believe there is a fuse for that and the system on my ZD is self bleeding so shouldn't have to bleed the lines. Let us know if you get it going.

MarineScott · May 3, 2010

OK Bled the injectors, Had the battery on a maintainer( the battery was 1/2 full of water before I started anything,filled with distilled water and charged) it cranked over faster and seemed like it wanted to start the slowed. Hooked it to a Kubota 4X4 in turned over fast then slowed,chugging like it wants to start but like it's flooded. I'm not familiar with diesels, can this be flooded? Heavy smoke out the exhaust as I crank. Is the battery too slow?

om21braz · May 3, 2010

What color is smoke ? Depending upon conditions. white could mean unburned fuel or other, black smoke would mean unburned fuel most of the time. Considering what you've already done, I'd now check the air filter - if dirty - don't clean it, replace - especially if single element. Hope it's not extremely dirty. If air filter looks good, make sure there is'nt some other obstruction to air intake. If all is well there, check engine oil level - a overfilled condition w/ thin look to oil + diesel fuel smell could mean injector issues. If none of these checks help in determining the problem, hopefully one of the many diesel smart folks on here can be of more assistance. Good Luck & let us know how everything turns out !

MarineScott · May 4, 2010

Can a diesel be flooded and does the speed of the starter ie:battery not up to full potential, have anything to do with a no start or flooding?
How would you un-flood a diesel?:confused2:

om21braz · May 4, 2010

Unlike a gas engine w/ carb, remember a diesel engine is only going to receive fuel during the process of cranking. If it is getting too much fuel, something is wrong - injector broken letting too much fuel in for example. The unburned fuel is either coming out of the exhaust in the form of smoke and/or washing down the cylinder walls into the crankcase. This is one reason to check the engine oil - see where the level is - is it overfilled/thin looking/smell of diesel fuel ? If you suspect there is fuel in the oil, I recommend not attempting to start it until the fuel system components have been checked out and the oil changed (engine oil). Just to note - my ZD21 will start in warm weather without preheating via the glow plugs - just puffs a little black smoke from exhaust maybe 3 seconds before starting and it turns over a little hard. Also my battery just decent - it is the original unit, never been charged and is 5 yrs. old - but probably will need replacing by next year.
Considering what you have already checked, I'd say check the air filter/system and the engine oil for fuel.