Kubota not starting

watgad · Jan 16, 2007

Update to my ongoing saga. Talked to previous owner. He was nice but had no advice(he went to the same diesel engine school I did). Talked to my mechanic bud. He instructed me to take out glow plugs and check. Plugs got fire red on ends. I thought we might be getting somewhere. I reinstalled plugs, tried to start-same song,second verse. I tried to bleed fuel lines again. The injector closest to the radiator seems to exert more fuel than the other injector. That is where I left it. In the next couple of days I will be taking Kubo to the mechanic. Sure was a short honeymoon. Thanks to all for the help and ideas.

psdx · Jan 17, 2007

I was never totally sure why since the fuel lines to the individual injectors are separate, but the manual says to start bleeding at the injector farthest from the fuel pump. I wasn't smart enough to overrule the manual so I have always done it that way. If you get bored before you send it to the mechanic, you might try doing it in that order sometime...

Once the line is purged of air, the spurts of fuel that come out of each injector line should be the same volume. A diesel engine needs fuel and compression to start (and sometimes heat when cold). Your glow plugs work - you've established that now. If you're getting fuel at all it should at least try to start, or start and run very rough. Since it's not starting for you, the next logical step would be a compression check. Having said that, this is kind of like the fuel thing - compression generally degrades in stages and maybe not equally among the cylinders. Therefore good compression in one or more cylinders should make it at least attempt to start.

Fuel delivery and/or compression that is sub-par will cause diminshed performance down to a point where it will prevent ignition. I would still attempt to purge the fuel lines once more, then if you have access to a compression gauge I would check that as well. Good luck.

Taiser · Jan 17, 2007

That was my next guess as well. If the glow plugs work and it's getting SOME fuel then you should hear it at least try to start or occasionally fire, unless the injector or hosing in too much fuel and flooding everything...if it's not then you're down to compression testing the engine and may need new rings on the pistons or you may have valve problems. Either one is no fun as it usually entails more to fix as you take things apart.

How was it running when you first got it? Was it smoking more than a normal diesel (other than start up)? Was there a heavy oil smell?

George2615 · Jan 17, 2007

Watgad,
Don't know where you are located but if your in cold country its possible your fuel gelled up. I just posted my thread in owning / operating about my tractor not starting this morning. My situation was twofold, a weak battery and gelled fuel due to cold temps in my area. Your post says your glow plugs are working and you are getting some fuel so it may be some other problem.

George

watgad · Jan 17, 2007

Thanks all for viewing and suggesting. I will try the reverse order of bleeding starting at injector furthest from fuel pump. I am not getting as much white smoke when cranking as I was when I first aquired machine. If I remove intake hose and place my palm over intake opening and crank, It will almost pull your hand in. When cranking and I put my palm over exhaust opening it is pretty good pressure being exerted. As stated once before It is Puff, Puff, Puff, coming from exhasust. Machine ran like a champ up until I peformed maintenance albiet I haven't had machine long and have not put it through any extended workout. It has been cold here (Memphis, TN area) for the last three days but before that temps have been in the 60's in the day and 50's at night. One note- when I remove oil fill cap there seems to be fuel in the area where the valves are located, not much, I tried to remove the fuel with a turkey baster and there was not enough in there to pull inside baster(probably irrelevant but this situation is strange to me and very baffling).

copperhead1967 · Jan 18, 2007

I'm wondering at the "just performed maintenance" statement you made. I know I have managed to do more harm than good if I skip a step while working on my tractor. I would retrace my steps to make sure I didn't fix something too good.
I had a issue where my fuel pump got unplugged under the tractor by a sapling . You should hear the fuel pump running as you warm the glow plugs.
There is a quick connect at the pump.

I had a problem with ice in both fuel filters once also. I removed them and took them in to warm, blew the water out and the tractor started right up.
Last thing is I have read that a lot of people installl fuel shut off valves for use when changing the filters. Since your tractor is used maybe one was put on if so its possible that its not fully open?

Tell us what maintenance was performed maybe someone can help.

rdsaustintx · Jan 18, 2007

watgad said:
One note- when I remove oil fill cap there seems to be fuel in the area where the valves are located, not much, I tried to remove the fuel with a turkey baster and there was not enough in there to pull inside baster(probably irrelevant but this situation is strange to me and very baffling).

Valve seals? How many hours on it?

Long as you are pulling glow plugs, do a compression test. Like everybody else has said, it only needs fuel + compression to run.