Kubota L6060 Engine failure

Rdrcr · Mar 6, 2021

^^^^
Agreed.

Although, as ridiculous as it seems, I can understand Kubota requesting a fuel sample to determine/rule-out fuel as a culprit before making a decision to fund the repairs. To me, that’s Kubota doing their due diligence before making their final decision.
That said, based on the information posted within this thread, I sincerely believe Kubota should pay for the OP repairs in full as a goodwill warranty.

Mike

MHarryE · Mar 6, 2021

Sobering story knowing I have the same model tractor about the same age. First off, what I said before, was for tier 3 when we introduced CRI. I retired during Tier 4 development but one item we did not want to carry forward was our injectors which had delayed several product introductions trying to reach reliability. As I remember, our minimum was near where you were - 3,000 hours. We wanted better but getting to 3,000 was a challenge. Starting Tier 4 development, we had the major suppliers submit injectors for accelerated wear testing. The winner was Denso, by a large margin, and I might be mistaken but I believe Kubota uses a Denso injection system. Also, our engine division told me diesel in Japan is very tough on injection systems and so have been developed for more durability. So I’ve thought of Kubota as best durability and your experience is a downer.

Fuel quality differs all around the world so a worldwide supplier like Kubota needs to design for the worst. That, however, is not a given. When I owned a BMW diesel in Europe, I received a letter from BMW telling be they experienced shorter than expected injector life in cars where the owners used lesser brands. They provided a list of brands to use throughout Western Europe. I have no idea how fuel is supplied in Europe but here in Minnesota all fuel comes from one of 2 Koch Bros refineries no matter which brand it is sold under. Brand additives are added when distributed but the base fuel is the same. I don’t expect Alaska fares much different.

Water - tougher on CRI injectors but they have a separator. I have water separators on my 2 pumps trying to keep my fuel most water free when it still has water. The separator on my L6060 now has the indicator near the drain separator level. At one time I plotted injection pump failures (tier 2) worldwide and used it to plot fuel quality. USA has a wide spread by region - I cannot remember Alaska but I pointed out we needed to design for all. And checking your current fuel - if it’s bad per their standard, will they say one bad tank will ruin a set of injectors? My book says only use #2-D at -10C up and #1-D under -10C. Knowing your weather, you probably use #1 much of your year and a #1/#2 blend during the summer. Our machines leave the factory with a blend.

This doesn’t give you much help toward the fix. I have given you my ideas earlier. I wanted to give you info from my perspective from product support at a division of the largest construction equipment Mfgr.

5030 · Mar 7, 2021

What a terrible thread. Sure am glad both my large frame Kubota's are Pre 4 mechanically injected and no frigging computer. In fact the only electronic device on either is a fuel cut solenoid. I'll never purchase any post 4 tractor and it's not just Kubota either, They all suck.

thclimer · Mar 7, 2021

This is a very unfortunate situation for the OP, I'll be watching this thread to understand the final outcome.

ruffdog · Mar 7, 2021

If it were my tractor, I would want the fuel from the tractor tested. What if someone dumped glue or paint in your tractor? You wouldn't want all the new parts to digest the same fuel that damaged the old parts, would you?

s219 · Mar 7, 2021

Technically, since the fuel system is past the warranty period, anything Kubota does is going to be goodwill on their part. To me, that means they have the right to test the fuel and do whatever they feel is needed to make the decision. I would not accuse them of stalling or delaying. If you want to press them for a quick decision, they are in their rights to just say no and get it over with.

tradosaurus · Mar 7, 2021

Dear OP, I hate to hear of your saga with your Kubota tractor. A tractor that has been worked like yours in a harsh environment (extreme cold and logging) with no major issues for 6 yrs and 2400 hrs is amazing.

The fact that your are in a remote area with only one dealer support compounds the problem trying to get your tractor fixed. I think most of us in that situation would have had the same result. And with only one dealer you definitely don't want to "burn a bridge".

With your tractor being part of your operation and therefore income, what kind of backup plan can you initiate so that you never lose income based on a non operational tractor? Are there extended warranties for tractors?

If I was going to lose, say, $50k, in income because my tractor wasn't working, $10k to get it operational as quick as possible would have been a no brainer.

AKForest said:
The engine was running fine then one morning it stopped running. Initial inspection on my part indicated an injector pump problem. The dealership said that the injector pump should not have failed. It could be anything. bring it in and we will put it on the computer and Identify the problem. They put it on the computer and agreed that the injector pump had failed. After replacing the injector pump, the tractor still wouldn't start. With consultation from Kubota, it was decided that the ECU had failed. it was replaced. Parts and labor by this time was in excess of $6,000. The tractor still would not start. At this point, they are looking at the injectors as also failing. Replacing those would bring the cost for parts and labor to around $10,000. The tractor is just a little over 6 years old with 2,400 hours on it. I have performed all the suggested maintenance as detailed in the Operators Manual. The people I have spoken to with much more experience with diesels than I, have said that they have never heard or seen three major components fail simultaneously like I encountered. I am reaching out to other Kubota owners/operators to see if they have had similar simultaneous/chain reaction failures with the L6060 tractor or other Kubota equipment with this engine.

Username Taken · Mar 7, 2021

US Diesel Fuel just simply sucks. There's no other way to put it.

When Bosch, who makes many of the HPFP's in modern cars and trucks, tests their equipment they test it in Germany. Makes sense since they're a German Company. Diesel in Germany is different than diesel in the US. It's better.

It isn't that we don't know how to refine better diesel, we sure do. It's just that there's a group of people out there (the EPA) that don't want us to. Don't get me started on them.

There's an ongoing war over Bosch CP4 pumps and the fact that they like to grenade once in a whle causing immense damage to the engines they're in. Big damage. GM went to Denso for their HPFP because of being getting the snot sued out of them for not making pumps compatible with American Diesel Fuel.

Cummins used the CP3 until 2019 when they used the CP4 for two years. I understand they've gone back to the CP3 for '21 after an outcry from owner/buyers.

I have the CP3 in my Cummins so I'm not all excited about it. But if I had a CP4 on my truck or a tractor with a mystery HPFP, I'd make sure and use a Cetane additive/booster and a winter additive and make sure it's right for cold (real cold) weather if I were in such a climate. Don't over-do it.

I don't know what Kubota is using on this particular engine but I bet it's a HPFP and when it grenaded it may have sent nasty all through the fuel system.

It's too late to save AK but the rest of you, if you have a HPFP, pay attention.

I hang on some diesel truck forums and it's real thing, these fuel pumps. Most people never have a bit of problem with them but the ones that do..... It's bad news.

You can help head it off if you understand your engine. Maybe not 100% guaranteed but you can sure improve your chances.

And make sure to send a 'Thank You' note to the EPA. I bet they'd love to hear from you.