CUB CADET 1572 Kubota 16HP Issue

[evan4434]

My kubota will start but acts like it is missing and then eventually will die. When it is starting it will blow a lot of black smoke at first and this was when it was 60 degrees outside.

Here is what I have done.

Bleed the fuel filter housing, injection pump, and injectors. I followed the videos that Vic had on youtube.

I also took the feed line to the fuel pump off and turned the pump on just to make sure I was getting adequate fuel. This was before I did all the bleeding.

After this I am still having the same issue. I then checked the oil and noticed it was about one inch over the full mark, and looked really runny and black.

What else could I check? Is there a way to test the fuel injectors?

Thanks

 

[evan4434]

Is there anything special in taking them off? Do I just take the hard fuel line off and remove the injector like a spark plug?

Thank you for your help.

 

[evan4434]

Update

I started it back up tonight and let it run for about 5 minutes and it seem to be running fine.

Now the nut that I broke loose on top of the injectors when bleeding the system is leaking. I have it tighten down all the way, but it is still leaking. How do I fix this?

Thanks

 

[traildust]

Update

I started it back up tonight and let it run for about 5 minutes and it seem to be running fine.

Now the nut that I broke loose on top of the injectors when bleeding the system is leaking. I have it tighten down all the way, but it is still leaking. How do I fix this?

Thanks

Just gonna have to start from the basics.
loosen the nut all the way and disconnect. Get a good look at the threads and the seats of the flares.
Sometimes, over torquing can split a flare if it's been stressed.

Scott

 

[evan4434]

Update.

I got the leaking on top of that injector to stop.

I have bleed everything many times now and still end up with the same issue.

Here is what is happening. If it would help I could upload a video of what is going on tomorrow to youtub and post a link in this forum.

When I first go to start it (60 degrees outside temp) it acts like it is flooded out and puffs black smoke but will eventually fire and after about 10 to 15 sec it will smooth out. Before starting I cycled the glow plugs for 30 sec. I even tried 60 sec the day before, but that did not seem to help much.

Then while running if I increase the throttle it acts like it is flooding out or running on two cylinders again and then it will smooth out. If I don't touch the throttle it will run fine unless I put a load on it such as engaging the mower deck then it will repeat the same issue and smooth out.

Is there anything else I can check?

Right now my thought is a bad injector that is sticking. I have added power server and let it run for about 1 hour tonight and that did not help at all. At this point I am at a complete loss other then pulling the injectors out and replacing them, but that is about $450. I could put new fuel filters in, but they seem to be fine and I have a very strong fuel flow.

Any help would be much appreciated.

Thanks

 

[traildust]

If it would help I could upload a video of what is going on tomorrow to youtub and post a link in this forum.

That would be extremely helpful to those in the know. If you really could do the video and post a link that would be great. Good as Gold!


Scott

 

[Milo Holroyd]

What you describe as a flooded condition, is just that. Your engine oil is diluted with diesel fuel. Your injectors need to be pulled and tested. Then your engine oil needs to be changed.
Milo

 

[evan4434]

What you describe as a flooded condition, is just that. Your engine oil is diluted with diesel fuel. Your injectors need to be pulled and tested. Then your engine oil needs to be changed.
Milo

I did change the oil, and still the same result. Also the oil looks fine since I changed it and has not be going up, so I think the previous owner might have just put a little to much in. So far I cannot find anyone in Iowa that knows what the heck they are doing. Does anyone know a kubota mechanic in Iowa that is any good? Our Cub Cadet dealer is also a Case dealer, but I have taken stuff there before and 9 times out of 10 if I cannot figure it out they can't and then they charege me $300 or more. When I called a large Kubota dealer here in Iowa 3 days ago the said they have never tested a kubota injector or had to replace one. There are a couple of other Kubota dealers I can call today in Des Moines I will give that a shot. Also of course they all want $75 - $100 per hour.

Thanks

 

[JWB]

Hey Evan,
Know its frustrating when people are incompetent. Just a thought but did you check the air filter and air horn for obstructions. You probably did. Sounds like its to much fuel or not enough air.
Hope that helps,
JWB

 

[evan4434]

Hey Evan,
Know its frustrating when people are incompetent. Just a thought but did you check the air filter and air horn for obstructions. You probably did. Sounds like its to much fuel or not enough air.
Hope that helps,
JWB

Ya I did and it looked good.

Thanks

 

[Milo Holroyd]

I did change the oil, and still the same result. Also the oil looks fine since I changed it and has not be going up, so I think the previous owner might have just put a little to much in. So far I cannot find anyone in Iowa that knows what the heck they are doing. Does anyone know a kubota mechanic in Iowa that is any good? Our Cub Cadet dealer is also a Case dealer, but I have taken stuff there before and 9 times out of 10 if I cannot figure it out they can't and then they charege me $300 or more. When I called a large Kubota dealer here in Iowa 3 days ago the said they have never tested a kubota injector or had to replace one. There are a couple of other Kubota dealers I can call today in Des Moines I will give that a shot. Also of course they all want $75 - $100 per hour.

Thanks

Keep in mind, it doesn't have to be a farm / implement dealer /service center.
Any large truck / engine shop, should have a pop-off tester. If worse comes to worst, I bought 3 new injectors for my L245DT for $90.00.
Milo

 

[evan4434]

Ok I feel like an idiot now. I found out why my mower was having a hard time starting.

On a Cub there is a electronic fuel pump and it was not on when I was trying to start the engine.

Here is the procedure you turn the key left until the glow plugs are hot then turn the key all they way right to the "ON" position then press the start button. I was just letting go of the key and it would snap back to the off position. The funny thing is the mower will still run even with the key in the off position it will just run like crap. Now I have been running it in the on position and it is running much better, but it still stumbles a little now and then.

I also did an injector test that someone told me to do. When the mower is running you crack the injector line at the injector if the mower starts to die then the injector is good. All 3 checked out fine with this test.

I am going to replace both fuel filters, and the air filter to see if that clears up my remaining stumbling issues.

Man I feel dumb! That is what happens when you have only owned gas mowers and tractors. I have a diesel car and truck, but that did not help me

Thanks everyone for your help so far!

I will not be posting a video now unless it has issue starting again.

 

[handyman]

No you shouldnt feel like a idiot your like everyone else with something new you have to find out how things operate and the next person that has your same problem jump in and tell him what happened to you and how to fix it. Thats called learning thru experience. handy

 

[traildust]

I will not be posting a video now unless it has issue starting again.

No video?

Hey, congratulations on hammering out the start sequence. I bet you were really happy when you figured it out.

Also, don't feel bad, we all do crazy stuff! The best thing about what you did was you came back and explained the fix. By doing that you just rose to the top of the flag pole amongst respect.


Thanks,
Scott

 

[evan4434]

Ok I am still having the same issue here is a video of the starting issues.

http://www.youtube.com/watch?v=Wlbrz3n-qcw

I am going to replace all filters this week and see if that helps. If that does not help what would you suggest as the next step?

Thanks

 

[traildust]

Ok I am still having the same issue here is a video of the starting issues.

http://www.youtube.com/watch?v=Wlbrz3n-qcw

I am going to replace all filters this week and see if that helps. If that does not help what would you suggest as the next step?

Thanks

That is a good video, thanks for posting it. That sure is a lot of smoke.

In your video when the engine finally started it sounded like it ramped up to a high RPM. Is that correct? If so is it because the throttle is in an advanced setting during start? Have you tried starting with the throttles lever all the way at its idle stop? It should start and not have to be advanced above idle.




Just for the heck of it I'll toss a couple of questions out there.

Are you sure there is, or hasn't been, any gasoline mixed in that tank?

Is there a fuel shut off lever any where in the system? SOmetimes near the fuel filter. If there is, is it actually open. Or maybe there is something restricting the fuel in the fuel line from the tank feed. Maybe some crap got in there.



Scott

 

[evan4434]

I GOT IT !!!!!!!!!!!!!

At least I think

I blew air down the fuel return line with the fuel cap off the tank, and guess what no bubbles. I then disconnected the return line and ran a clear line into a pop can and it fired right up and ran great. In the process of removing the tank I closed the fuel petcock (in the direction I though was closed) and then all the sudden a ton of fuel started pouring out my return line. The feed and return lines must have been switched around at sometime. I hooked everything back up and it runs fine now.

Now I did check the feed line for fuel flow with the petcock in the closed position and it feed great now I know why. Now I know which way is open and closed on the petcock and which line it is hooked up to. From what I have heard this is common thing to do on these Cub diesel because there is a screen on the petcock that can plug, so people reverse the feed and return lines so that the feed line does not get plugged.

Thanks everyone for your help, and I hope I don't have to post a new post with this issue again.

 

[traildust]

I GOT IT !!!!!!!!!!!!!

Well congratulations Evan


Thanks a mill for posting what you found. That's great info that could help others.


Take care,
Scott

 

[Michael]

One other thing to check is the muffler. Prolonged use of the engine at idle or slightly above idle when plug up the muffler with soot.

Yanmar tractors are known to do this and what most do is remove the muffler and test run it (I realize it will be loud) and play with the throttle and loading the tractor with something attached to the PTO and see if this works.

I have in the past had a tractor that I was working on that had a similar issue and I removed the muffler and tested it and the ran fine. To clean the muffler inside I soaked it over night in diesel and then used a pressure washer and got 95% of the soot and garbage out of the muffler. I reinstalled it and ran the tractor for a hour mowing without a issue. Once in a while after doing this it did belch out some black smoke but the tractor performed fine.