Kubota L1500 will not start

[alchemysa]

Just to make you look silly it will no doubt start as soon as it even smells a mechanic. But seriously, are you sure the plugs are warming up enough? Or warming up at all? If you've done everything else right this is starting to sound more like an electrical problem to me. From a cold start I need to hold the ignition key in the pre-heat position for about 10 seconds. Some tractors take even longer. Are you doing this? I dont know how you'd check if they're warming up. I've never had to do it, and my tractor is too far away to test, but I guess you could just carefully put your hand on the plugs to see if theyre warm.

 

[mechanic]

how did you come out after making your checks? I was welling to bet you let air into your system. The same can happen if you let it get to low on fuel.

 

[alchemysa]

Sorry to harp on this and possibly sound like I'm trying to teach you to suck eggs, but are you fully familiar with the operation of the start key? If it's like mine, the ignition switch has four positions. OFF/ON/PRE-HEAT/START. In the ON position you might see a couple of lights come on on the instrument panel. Don't be fooled into thinking that these lights indicate that the plugs are heating up. To heat the plugs you have to turn the key to the next position and hold it. (It's spring loaded). You might then see an extra light appear on the panel. After 10 seconds or so you then turn the key further to the start position. This simple mistake can easily fool an inexperienced operator who has received limited instruction. Its possible that the two previous times the tractor started it was still warm from recent running, and started without pre-heating. Sorry again if I'm telling you the obvious but you didn't say how experienced you were with diesels.

 

[watgad]

Thanks to everybody giving me advice. I am not experienced with diesels, I have tried to start engine with key in all positions. My glow plug inidicator on the dash is in the appearnce of a lightning bolt. My key positions are Off, On with headlamps illuminating, On without headlamps illuminating(this is the position where I turn the"knob" (located away from ignition key) to the left for my plugs to warm up. The lightning bolt will turn red. I then turn the "knob" to the right to crank/start engine. Being of unsound mind but sound back and hard head I am going to start from the start and try to bleed air from system one more time.

 

[billbill1]

Is the filter now full of fuel? Make sure it is before you start bleeding, that's where this all started in the first place, if I understand you correctly.

 

[watgad]

Yes, I have clean fuel in the filter.

 

[RobJ]

Hey Rob,

I called myself today loosening the injector lines at the top of head. I tightened back down, but engine would not start.

Did you crank it over when they were loose? Was the fuel coming out in spurts? You should get a good solid spurt, not a fizzle or bubbly one.

Don't give up, you'll get it. It did run once!!

 

[gilbertmsg]

Don't feel bad, I just did the same thing. Just purchased Iseki TU 1700 and replaced fuel filter without filling the bowl up back up. Having hard time getting air out of system. Will try to bleed again tomorrow. Let me know if you hear of a better tip. Was getting plenty of black smoke out of exhaust before I messed it. up

 

[KJM]

[Hope this is not needed and you have it running now!]

There is an air bleed screw on the top of the filter housing on all the Kubota's I've seen (but I haven't seen an L1500). On my ancient B7100 there is one too. When you open the filter or stupidly run out of fuel you need to open the screw up. Keep it open till the bubbles stop. You need to screw it in while the fuel is flowing out. Messy, but essential. You now have the fuel filter full of fuel.

The next step is to clear the line from the fuel filter to the injector pump and the injector pump itself. There is a bleed for that too. AFTER the fuel filter is bled, you need to open the bleed there and keep it open till you get fuel (and no air). On my B7100, it ran out of fuel at the top of the steep drive way - and gravity wasn't working - so I had a mate crank it over to get the fuel to flow out. Once you have fuel here, it usually starts and splutters till all the air is out of the injector lines. If it doesn't catch, you then crack the injector lines. Keeping well clear of the high pressure fuel spray! A piece of paper put near the cracked line will tell you if you have fuel mist - don't use your body!

There is no short cut to bleeding diesels - you must do it right - which means being systematic. Cracking injector lines randomly before you have assured fuel to the pump is pretty pointless, for example.

I agree with my almost-neighbour alchemysa tho' - the glow plugs seem essential for the kubota's around here. My B7100 won't catch even on a 40C (105F) day unless it has some glow plug assistance (the first time, after that it's fine).

Since it was working before you did the maintenance, it must be air in the line - so keep at it - you need to be able to get a diesel going again if you own one!

Hope it helps

 

[charlz]

On my B7100, it ran out of fuel at the top of the steep drive way - and gravity wasn't working - so I had a mate crank it over to get the fuel to flow out.

The B7100 owners manual I have says to crank the engine when bleeding the injection pump.

1)fill tank with fuel, open petcock
2)twist off air vent plug at the top of the filter with two turns
3)when bubbles disappear from fuel coming out the plug, twist it back on
4)Open the air vent plug on the fuel injection pump
5)Pull the engine stop lever to stop the engine and start the cell starter for about 10 seconds.
6)close the air vent plug when air bubbles disappear from the fuel flowing out.


When I did this on my b7100 I took the engine stop lever to be the decompressor knob, but maybe they actually meant the one that throws the throttle forward to cut the engine? That would seem a little counter intuitive as you would want fuel flowing to the cylinders?


From the pics the 1500 engine is laid would different but maybe this helps. I know you have bled the injectors but have you bled the pump?

Charles