Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy.

   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #1  

GeorgeSB

New member
Joined
Jul 17, 2017
Messages
23
Location
Colorado Springs, CO
Tractor
Kioti DK35
Fuel cap and well weaknesses. A dangerous situation by design, dangerous for the tractor's engine.
Kioti DK35, early 2003 build.

I use the term, "conspiracy" to mean that one design weakness we might get away with but when combined with another and another and add environmental factors and even operator error(s), we can lose the tractor, tractor's engine or cost us dearly.

I'll be up front and not hide anything about the situation. Unfortunately I don't have a protective storage for my tractor, she sits outdoors.

This situation I'm about to describe could occur to any tractor operating or caught in weather with this Kioti design.

I love my Kioti tractor. She's served me very well all these years. She's saved lives. She's pulled cars out of snow drifts and brought mothers and children home to safety when otherwise they would have been trapped in the horrible winter storms. She's made easy work out of large tasks. I don't know how we ever lived without this tractor. I use her quite often. I've got somewhere around 650 + hours (not sure because the cheaply made with plastic part, tachometer cable was broken for a time. Another weak design for another story.)

The Kioti design is generally robust. The engine is strong and many aspects of the design are very forgiving. But I've run across some really weak areas of the design. Some of these weaknesses floor me. I don't think Kioti should have been so cheap? I don't know how else to put it.

I want to speak to just one here. The fuel filling spout, protection, and overflow. Clean and water-free fuel is paramount for a fuel injected diesel motor. Everyone knows. But Kioti design engineers/production cost control people blew it IMHO.

On my Kioti DK35 tractor there is a fuel spout on top of the tractor. I find it difficult to refill with a 5 gallon container of fuel. There isn't an easy way. I have a spout that works quite well. But one must lift the 5 gallons on top of the machine and balance my feet on a tire or something to get high enough to tip the container. But that's not the concern. I'm certain there are many clever ways around this. And if you have a fuel container or a pump, it's hardly worth mentioning. For a small operator like myself it's an inconvenience at most. This isn't the issue I'm going to address.

The fuel filling spout has a cap. The cap is surrounded by a well with a drain. The cap and well are covered with a lid. Here's the problems. The problems can conspire to do harm to your tractor.

The lid is extremely cheaply made and flimsy and of a plastic that deteriorates in the sun and is very vulnerable to wind. In some environments it is totally inadequate. What we have here in high plains Colorado is ample sun and constant wind. I've gone through several lids now. The lid is a very weak design. Crazy weak design. There is also no fastener to hold the lid down against strong winds. It just flops down by gravity into position. The lid also isn't sealed. Water from heavy rains can get past the lid and go down to where the fuel cap and well are sitting above the motor. Almost certainly, water will get past the lid in wind driven rain at times. If that lid should lift the rain gets in. If even a spec of debris is in there, water will gleefully get past the lid. If the lid lifts and breaks, which has happened to me twice now, there is no protection at all, be it marginal to begin with.

I've had a terrible situation where the fuel lid broke off and very heavy wind-driven rains fell onto the fuel spout cap. That would not be a problem by itself. But with the well surrounding the spout having a lip above the bottom of the fuel cap, the well can fill adequately in heavy rains to reach the height of the very bottom of the fuel cap when snugged down, then capillary action can draw water into the fuel tank. This can happen even with the fuel cap on properly and tightly. (the people I bought it from had it cross threaded when I bought it and could barely get it off. Accidental cross-threading could make the cap much more vulnerable to capillary action. This cap and thread could be better designed as well.) And it can happen with an in tact lid on. Just a few lifts of the lid by wind and wind-driven rain flows down past it.

Of course all of these weaknesses are exacerbated if any of the following apply:
Cross threaded cap
Cap that doesn't perfectly seal
Thread are no longer perfect
The tractor isn't pitched favorably for the well to drain quickly
Debris in the well drain
Heavy rains
High winds
Broken or missing fuel lid
Debris in the fuel lid interface to the tractor body
Others ...

One day my wife complained the tractor was hard to start. I had no idea what the problem was. I looked it into long enough to finally learn there was some water in the fuel. I had to tow it back to my garage. The repairs took a lot of work, research, labor, and perseverance. Fortunately for me I ended up having only had to replace the glow plugs. I ended up replacing the heater glow plugs after taking quite a bit of the fuel delivery system apart, draining and replacing fuel. My tractor was down a week or so. I was very worried I'd never recover the engine. But fortunately, the engine is robust, I got her going again. She's been serving flawlessly for some time since.

Here are the measures I've taken to prevent a recurrence. I tore out the rubber well that the fuel spout and cap sit in. If there is a fuel overflow while refueling, yes, it might get onto something, instead of neatly going down the overflow drain tube to the ground. But it's worth it! It is now extremely difficult for moisture, water, to stand at all in the area of the fuel cap. It's virtually impossible for water to stand high enough in any way to be drawn into the system from underneath the marginal cap. Also I'm no top of keeping the lid replaced as they break and fail over time. I've even covered the engine with plastic or other materials to keep heavy rains from pooling onto the fuel door lid. I am extremely careful to slowly start the cap threading and once i know it is correct then completely tighten her all the way down. I frequently visually check the area around the fuel cap for any standing water, right after rains.

I'm not going to mention the weak and short-lived fuel bowl "pot" that is talked about elsewhere. I just ordered a replacement. I don't think it has anything to do with the water issue.



I've not seen a recurrence of the problem since the repairs and changes. That is true in spite of heavy rains for many days and high winds as well. I also added frequent checks of the fuel pot for water potential or coloration. Will be more difficult with the new designed fuel pot that is milky colored. Darn!

I may at some point design and build a better fuel lid door with a latch and a water-tight seal in a manner that should and could have been included in the original design by Kioti. I also feel rather "forced" into finding the cash (I'm retired) to self-build a garage just for this tractor. She seems weak to the environment in numerous ways covered elsewhere (sun does a number on destroying all the plastic, the seats, the hydraulic lines. The wind drives dirt into the poorly designed shifter linkages and other moving parts, so we have to clean and lube quite often, etc.) . I may also study the fuel cap more carefully and if I don't think it is adequate, order a cap that seals better.

It's shortcomings like this the befuddle me in the Kioti design and build department. Taking short-cuts where so little effort and cost would be involved in a better way. I've seen a number of short-cuts now in the Kioti design, some affect safety, some affect longevity, some affect operations, some affect our backs. This is the disappointment of the Kioti. I have no idea if you'd find similar problems in other tractors, such as Kubota, Deere, Ford, New Holland, etc. This is the one and only tractor I've ever owned. I still love my Kioti. I've just had to learn and adapt and make some improvements of my own.
 
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   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #2  
If the well can catch fuel and direct it to an overflow tube down to the ground, why wouldn't water follow the same route and just be directed down to the ground?
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy.
  • Thread Starter
#3  
If the well can catch fuel and direct it to an overflow tube down to the ground, why wouldn't water follow the same route and just be directed down to the ground?

Good question.
I'm not an "expert" and haven't done time-lapse photography studies, so here's speculation.
If the well was designed for a little fuel overflow and not heavy rains, there's a lot of options for pooling of water.
if the tractor is not on flat and level, ground, and we don't have perfectly flat ground, it could exacerbate pooling.
If the outflow is in any way dirty it could exacerbate.
If the inflow of water is very heavy....
All I know for certain is that it happened.

It's possible that the well wasn't to blame, of course.
That leaves me only to think that "somehow" the cap allowed water in on its own.

I don't know of another entry point for water, except for refilling with water in the new fuel or refilling in the rain or some such.
We didn't refill the tank.
It rained heavily and high winds for days before this failure mode.
I'm conjecturing with what I can observe.

Thanks for asking the logical question!
 
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   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #4  
Any decent canvas shop could make you a cover for the center section from the grill to the PTO. Ask at your local boat shop for references.

My 2014 Kioti has a substantial metal door over the fuel filler. I use a 5 gallon plastic diesel can shaped like a cube, and I installed a flexible plastic fill line on it in place of the spout. I set it on the hood, pull out the fill line, and tip it on it's side with the line in the neck of the tank. It's a CARB-approved can, with a non-CARB-approved spout, but is unvented. It takes a few minutes to get the first four gallons out, then I hold and tip the can as needed. A good three-step stepstool would be needed if I were not 6'3. I know others who use racing fuel containers and/or siphon pumps.

An alternative would be to go to a race shop and see if they can help you either extend the neck of the tank or help you install a better cover. A good boat shop might also have a better cover.

Something like this: Amazon.com: Bully BBS-231 Black Bull Series Gas Door: Automotive
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #5  
If there is a fuel overflow while refueling, yes, it might get onto something, instead of neatly going down the overflow drain tube to the ground.
Well... Hawkeye beat me to it. I was re-reading the essay above and the same thought crossed my mind.

Firstly, these tractors are not designed to be stored outdoors in all weathers. None of the common colours are. Not without some rudimentary protection anyway.

I feel some personal responsibility may be called for and I think you're being a little harsh on the Koioti/Koreans here. They have provided a catch area and a drain pipe for any fluid that finds itself loose around the fuel cap.

If it's anything like the 'Green' or 'Orange' ones I've seen it will be 10-13mm ID and be more than capable of handling rain. It's a straight path to ground. Not even an "S" trap like under the kitchen sink.

Where I have seen the drain struggle is when debris has blocked the pipe.
You bought the tractor second-hand so do you know if the pipe was/is clean? Fuel spills of diesel cause the collection of oily dust/debris which eventually blocks the overflow pipe. At best, it restricts the flow.

The fuel cap is vented by design. The lid is there to protect it from direct water. The drain pipe is there to channel fluid (water/diesel) away from the console (electrics). Even a strip of Duct Tape will hold a fuel flap down.

The most common source of water in diesel fuel is from contaminated supply and, to a lesser extent, condensation. Is it possible you had a fill of diesel which was contaminated? Everyone answers "No" to this question, worldwide...

With regard to the Water Seperator - I have read the long thread elsewhere - I wonder if any of you Kioti owners have considered fitting a better quality unit from a JD or Kubota? They would be a direct replacement and have proven credentials in respect of the bowl, transparency and (JD at least) the Red Ring water indicator.

UV attacks the plastics. Outdoor storage exposes your machine to attack all day, every day.
Regards,
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #6  
Holy Crap! I have to re-engineer things just about daily. Nothing is made with any care these days and after being thrown together they push it off the line onto the retail buyer's upcoming headache area. DO NOT buy a new tractor under any circumstances, or be prepared to be astounded by the junk we get thrown at us- and are EXPECTED to accept with no whining!

Example: I bought a brand new 2015 Husky 322T ride mower; nearly $6,000. The front transaxle had a palm of my hand sized silicone glob jammed in at the axle shaft! WHY?! Because at the factory the rocket scientist assembling the transaxle decided to pass the leaking like a sieve unit out the door to my retail dealer, so I could buy it and have it replaced under warranty. It NEVER should have left the factory to be delivered to a retail customer, but it was. SOP these days. Trip up and back to deliver and pickup the mower, time and gas wasted in both directions, 1 hour each way, TWO times. So at least 4 hours of my life wasted because of some idiot at a factory. AND then they reinstalled the brake cable routed wrong, chafed the belt and the cable. Now the spring tensioning the same cable is damaged and needs replacement, AND the 'new' replacement transaxle seems to be leaking too- AND it's off warranty, so if it needs another transaxle it will likely be at my expense. If I hadn't had the bad one to begin with maybe the current one would have failed during warranty and I'd now be replacing the first factory installed transaxle instead of the one that should never have left the shop winding my warranty clock down so that when I need a replacement I end having to pay for it! Getting my drift?....

Show us pics of the offending area/parts and we'll design and sign off on a better design and send you on your way.

As pointed out, you live in a high wind, and rain/snow belt.
Take further preventive measures to make up for the 'deficit' that you think is Kioti's responsibility.

I'd try a appropriately sized tuna can or coffee can or similar and place a rock on it or on the original fuel cap door to hold it closed, or similar. Or build or buy a shed, or carport or aircraft hangar or whatever to block the wind, rain, snow, and flying dust, dirt, etc.

Paint and hydraulic hoses deteriorating in the sun?! Ha! What doesn't. Get some Armor All, or similar and wax your tractor's hood, etc. Put a tarp over it and hold it down with rocks, stakes or bat guano!

Next!
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #7  
My DK35se is a newer model. The fuel lid door is made of chrome plated steel. It is spring loaded to stay shut or open when fueling. The fuel cap has a gasket for sealing out water and debris. The well and drain work very well for containing any fuel spills and drains them harmlessly to the ground, but of course an occasional inspection for debris that may accumulate to stop up the drain would be in order. Perhaps the newer door and spring could be retrofitted to your older design?
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #8  
Tarps are cheap, you can't blame Korea for your tractor deteriorating in the weather. If I didn't have a garage to keep mine in I would have at least built a pole shed or car port to protect my hero. With the way the UV's are now days nothing will last sitting out in it for years.
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #9  
I could never understand why anyone would spent thousands of dollars on a tractor and then not build in some protection for it. I often see machinery being used and then the operator just shuts it down and walk away. I know money is a factor in many of these cases but a tarp is cheep and a lot of times given away at Harbor Freight.
 
   / Fuel cap and well weaknesses. Dangers for tractor's engine. Design flaws conspiracy. #10  
Agrreee 100 percent on these last two posts. You can make a pretty nice Q hut from bent conduit and shrink tarp for a couple hundred clams.
 

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