Oil & Fuel Kubota BX2360 choking up in the cold

[ruger.john]

It seems like it is freezing up which it has done before. The dealer has had it several times and blamed the fuel freezing up. Took off the tank blew out the lines replaced the filters and fuel pump and put in new fuel. Worked for a few hours a day or so ago but temperature today was below zero and it only worked for 30 minutes when it had all the same symptoms and just made it back to the shed(un-heated). Waited a while and it started up and ran fine. Filters did not look frozen up. We are adding the additive recommended by the Kubota dealer. I am beginning to think it is not the fuel. Any feedback?? Thanks

 

[jbrumberg]

Welcome to TBN. When the tractor starts lugging" is there any exhaust smoke? and if so what color?

 

[dodge man]

There are some threads on here about adding a fuel filter setup from a B series Kubota or a Racor system. The stock filters on a BX suck. Mine froze and/or plugged up twice. Even with the Racor on mine and a fuel additive, mine gelled up this winter. The advantage of the Racor is it has a clear bowl and you can see the gelling.

 

[RjCorazza]

If it ran for 30 minutes, limped to an unheated garage, then after a while parked it ran fine I doubt you have a fuel gelling problem.
My ZD mowers use the same electric fuel pump and inline filters. The ZD’s will somewhat run (intermittently) with a bad pump, and the first filter can clog fast causing fuel starvation. Even if the pump or filter are not your current problem, consider dodge man’s advice on replacing the first inline filter with something better. My ZD’s both have large 2 micron spin on filters, and non-oem electric pumps (Mr. Gasket diesel pumps).

 

[BeezFun]

If you just cleaned the tank and lines, I'd leave the filter element out and see if the problem goes away.

 

[Peter 315]

If you leave the filter off you might ruin the injector pump:2cents:

 

[dodge man]

Do not leave the filters off. Below zero temp the fuel probably gelled in the filters.

 

[fishpick]

@ruger.john - you said you are running fuel with "adding the additive recommended by the kubota dealer" - what are the additives?
What's the temp - you say cold but that's relative... my friends in South Florida consider 50F "freezing"
Is the diesel you replaced the tank with "new" or "old" - I see you are in Quebec so I assume like here in NY there's a summer blend and a winter blend up there...
Just looking for a few more details!

 

[Egon]

Fuel gelling & plugging filter.

When warmed sits in shop in the shop engine heat melts gelled filter and let's you start again.

 

[JWR]

If it ran for 30 minutes, limped to an unheated garage, then after a while parked it ran fine I doubt you have a fuel gelling problem.
....

I disagree completely. I assume you meant "below zero" as below zero F and more than 17 below Centigrade ? If YES, continue reading what I am about to say. If NO forget my comments here. The symptoms you describe are typical of diesel fuel gelling. Not actually "freezing." It is guaranteed to happen at zero F and I have seen it at about 11 deg F. with an automotive diesel. The warmth from running it a short time, being inside a closed place no matter heated or not, probably loosened up the fuel flow. This fits perfectly with a case where you had added an additive recommended by the dealer (!) and you were right on the edge of more serious gelling. It is also a perfect illustration of why I claim that additives are only a marginal solution that help in a limited way and DO NOT fix the problem with any certainty. Additives are just a maybe of a fix. Most of us do not want a Maybe. I have said in many posts that the real and certain fix is to mix #1 fuel (kerosene) with your normal diesel #2 fuel in a 50-50 mix. I repeat one more time, this is exactly what the heavy equipment operators do in northern VT and NH and places with climates similar to yours. In the very cold weather, just run half kerosene. It will hurt absolutely nothing. The lube qualities are only slightly degraded and that for a relatively short time. Your power output will be reduced by a tiny % and you will NEVER notice either of those 2 side effects. By the way, your experiment essentially shows how much the additive lowered your gelling point (or rather how far it did NOT lower the gelling point.) Lowered it some, just not enough. The additives won't hurt anything but if you really want a reliable solution, mix in the kerosene. I do not have the numbers but ask your local heavy equipment operators -- they can tell you how far below zero F the 50-50 mix will cover you.
By the way, there is no reason at all to get into these messy (and potentially problem causing) screwing with filters. Once the engine is warmed up running on a usable mix of fuel for a while the gel will be "disolved" in the various filters. Only if it was so bad you could not get it to run at all would screwing with filters be warranted. Even then it would be better to just move it to a warm place for a few hours. Good luck and let us know how this all came out.

 

[crazyal]

You may want to check the filler cap. I do believe it should be vented. If it can't suck in air as you use fuel it could cause a problem. Moisture could be plugging the vent when temps drop. It's an easy check, just loosen it the next time you have the problem and see how it runs.

 

[RalphVa]

JWR is right. OR, if you can get heat onto the fuel filter, it could keep it from gelling, or run up to 50% kero. Had gelling one time in 39 years of running diesel cars. That was one morning at -22 F in Vermont. Started up fine with lower radiator hose heater run for about 20 minutes. Drove down the road, and it stalled. Let sit a minute or two. Restarted. Drove down the road another mile or two. Quit. Same thing. Finally ran without stopping. Big fuel filter on a Benz is right next to the engine block. There is a tiny pre filter, similar to those silly ones big American V8s had upstream of their carbs. It never plugged.

Ralph

 

[Egon]

In most northern places there is a summer diesel and a winter diesel supplied by the distributors. The suppliers will switch between the two as per the season.

 

[JWR]

In most northern places there is a summer diesel and a winter diesel supplied by the distributors. The suppliers will switch between the two as per the season.

That is what is SUPPOSED to happen. The problem is the user filling his tank has no reliable way to know whether the distributor did the winterization or not. If he did, how much and how far down is it good for ? Where does brand A executive sitting in some office tower deciding fuel distribution policies think the border is between 'northern places' and non-Northern places? Depending on distributors winterizing fuel is a form of Russian Roulette. I've had the exact same experience as RalphVA describes above.

What works every time is to check the temperatures/forecast and if it may go below about 12 or 14 degrees F, then mix in some kerosene, up to 50%. What works some of the time is buy into the myriad varieties of additives. What stands an unknown % risk of stalling out with gel is to depend on distributor winterization.

 

[Egon]

That is what is SUPPOSED to happen. The problem is the user filling his tank has no reliable way to know whether the distributor did the winterization or not. If he did, how much and how far down is it good for ? Where does brand A executive sitting in some office tower deciding fuel distribution policies think the border is between 'northern places' and non-Northern places? Depending on distributors winterizing fuel is a form of Russian Roulette. I've had the exact same experience as RalphVA describes above.

What works every time is to check the temperatures/forecast and if it may go below about 12 or 14 degrees F, then mix in some kerosene, up to 50%. What works some of the time is buy into the myriad varieties of additives. What stands an unknown % risk of stalling out with gel is to depend on distributor winterization.

Up in the frozen north I've never had a fuel gell issue with filling station Diesel.

 

[JWR]

Up in the frozen north I've never had a fuel gell issue with filling station Diesel.

Glad you have not had the problem. There was no bullet in your chamber when the trigger was pulled. Very likely the fuel distributors are keen on the issue in places like Nova Scotia. It is very possible that fuel distributor practices have improved too.

I have had the problem (automotive diesels) in Troy VT near the Quebec border (at around 10 below zero F) and in West Virginia going over a mountain where the temp dropped below around +10 deg F.

How far down in temp will the filling station fuel protect you ?

 

[dodge man]

I also NEVER had a problem for several years until this winter. With the Racor setup and the clear fuel bowl, you could see the problem. That was with an additive. Mine was gelled up so bad I pretty much had to change the filter. I'd say JWR is spot on with his ideas. Additives help, but how much?

 

[Egon]

Glad you have not had the problem. There was no bullet in your chamber when the trigger was pulled. Very likely the fuel distributors are keen on the issue in places like Nova Scotia. It is very possible that fuel distributor practices have improved too.

I have had the problem (automotive diesels) in Troy VT near the Quebec border (at around 10 below zero F) and in West Virginia going over a mountain where the temp dropped below around +10 deg F.

How far down in temp will the filling station fuel protect you ?

Lowest I filled up was -45C. Happened more than once too.

 

[check]

Gee, I don't understand this gelling problem. My 2009 BX25 has always started in temps as low as -30 or even lower. I have never seen any gelling.

 

[repete]

I disagree completely. I assume you meant "below zero" as below zero F and more than 17 below Centigrade ? If YES, continue reading what I am about to say. If NO forget my comments here. The symptoms you describe are typical of diesel fuel gelling. Not actually "freezing." It is guaranteed to happen at zero F and I have seen it at about 11 deg F. with an automotive diesel. The warmth from running it a short time, being inside a closed place no matter heated or not, probably loosened up the fuel flow. This fits perfectly with a case where you had added an additive recommended by the dealer (!) and you were right on the edge of more serious gelling. It is also a perfect illustration of why I claim that additives are only a marginal solution that help in a limited way and DO NOT fix the problem with any certainty. Additives are just a maybe of a fix. Most of us do not want a Maybe. I have said in many posts that the real and certain fix is to mix #1 fuel (kerosene) with your normal diesel #2 fuel in a 50-50 mix. I repeat one more time, this is exactly what the heavy equipment operators do in northern VT and NH and places with climates similar to yours. In the very cold weather, just run half kerosene. It will hurt absolutely nothing. The lube qualities are only slightly degraded and that for a relatively short time. Your power output will be reduced by a tiny % and you will NEVER notice either of those 2 side effects. By the way, your experiment essentially shows how much the additive lowered your gelling point (or rather how far it did NOT lower the gelling point.) Lowered it some, just not enough. The additives won't hurt anything but if you really want a reliable solution, mix in the kerosene. I do not have the numbers but ask your local heavy equipment operators -- they can tell you how far below zero F the 50-50 mix will cover you.
By the way, there is no reason at all to get into these messy (and potentially problem causing) screwing with filters. Once the engine is warmed up running on a usable mix of fuel for a while the gel will be "disolved" in the various filters. Only if it was so bad you could not get it to run at all would screwing with filters be warranted. Even then it would be better to just move it to a warm place for a few hours. Good luck and let us know how this all came out.

Even in Western Washington state where temps do not get extremely low I used to mix a 50/50 #1 and #2 fuel for our diesel fuel fire station APU's that sat in the open. Although maybe every 30 years we get down to 0 degrees F, I did not want to have to deal with any fuel issues at that time should the rare north front happen. Power output may have been reduced a tad but it sure beat the alternative.