Regen problem L 3901 anyone ever have this?

North Idaho Wolfman

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I can say it works incredibly well, the marine industry uses it because all the moisture issues in their fuel systems.

I think one reason that you don't find it everywhere is that it's expensive, too much risk for wally world and the such kind of places.

There are three similar product, starbrite, startron and Soltron, I've never use the other 2 and they might work the same (I think one is specifically for gasoline) but I don't want to change considering I've had excellent result from Soltron.
 

wgator

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I can say it works incredibly well, the marine industry uses it because all the moisture issues in their fuel systems.

I think one reason that you don't find it everywhere is that it's expensive, too much risk for wally world and the such kind of places.

There are three similar product, starbrite, startron and Soltron, I've never use the other 2 and they might work the same (I think one is specifically for gasoline) but I don't want to change considering I've had excellent result from Soltron.
Want to know a little secret about Soltron? Read the below attachment from the soltron FAQ page.

Soltron FAQ.jpg
 

SidecarFlip

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I have to sat I tried the Startron and it didn't do squat for my gas engines so I went back to Seafoam.
 

69 SS

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2015 L3901 HST,with Canopy,LA 525 FEL with SSQA bucket
Sep 26, 2015
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Old Gray Stallion ain't what he used to be,ain't what he used to be,ain't what he used to be. Supervised son in law, did water separator,no slime ,little sediment bottom of bowl,drained tank, 10 gal. fresh diesel with Seafoam, changed HST and fuel filter. All this after we watch the DIY on YouTube video. Cranked "Big Orange" , no leaks . after SIL left I decide to do all the grease fittings,get grease gun,last dummy that used it left it empty, Doh. Didn't have enough a$$ to pull rod to compress spring,ain't what he used to be ain't what he used to be.
Thanks to all ,especially the link to the DIY you tube video. Not for me ,but really help SIL get a clue. Now if I can get him back to pull on grease gun. It's 18 volt Ryobi, maybe there is a video for this to help him!!!
Thanks to all ,and good luck on all your projects.
 

angelo c

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Dec 23, 2019
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I have to sat I tried the Startron and it didn't do squat for my gas engines so I went back to Seafoam.
Im more concerned for my HPCR Cummins and Kubota Diesels where Bio's can hurt injectors. Clean fuel is the key to smooth HPCR's. Anybody have any experience with the Cat fuel filter add on for Diesels on Kubotas ?
filtration fears is about the only thing that keeps me up at night....( yes I have been through the DPF replacement shuffle)
 

lugbolt

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wanna know another secret?

Moisture in the fuel, even treated, is still there. The moisture didn't go anywhere; it is simply dispersed and nothing more.

Guy from startron "sold us" on it too; well "sold them" (not me). He took a quart jar, filled it about 1/2 full of some 87 octane we had in the shop, then put about 4 oz of water in it, shook it up and let it sit on the counter. It kinda dispersed but settled out. Then, he used whatever amount of startron in the mixture of water/gas, closed it up, shook it, and set it back down on the counter. Couldn't see the water-but the gasoline (mixture) was more of a cloudy color. For the 5 min or so I was watching, it didn't settle out.

BUT wait there's more....

Next morning I came in to unlock the doors and open up for the day's business. Glass jar sitting on the counter. In the bottom was a layer of gasoline and on top of it a tiny layer of something else (I assume startron), then the gasoline on top of it. My boss bought a ton of startron the day before. When he showed up for work, about 10 min after I did, I showed it to him. I don't think he was very happy about his order--just said "well I hope y'all can sell all we ordered".

Try it sometime. That water didnt' go anywhere it just got dispersed and you put more "stuff" into the fuel; and who knows what that "stuff" is and what it can do to injectors, etc. Remember, gas DI engines nowadays are using injectors that are somewhat similar to diesel injectors; just at a little lower pressure.

As I've always said; if you take care of your gas and use prevention as treatment and nothing more, you'll be fine. Only one time in the last, gosh 20 years, have I had any personal fuel issues and that was not the fuel or aging or water, it was a TICK that got into the carburetor somehow and plugged the main jet on my old boat motor. Cleaned the carb on the sandbar in about 10 minutes, continued on.
 

GeoHorn

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I can add to lugbolt’s good observations. Most fuel stabilization additives actually only suspend water so that it will pass on thru the system, the intent being to dis-arm it in such a fashion that it doesn’t cause a complete shut-down or failure.
Things like water still have to be pumped all the way into the cylinders where it can be blown out the exhaust....hopefully without causing immediate failures.

You’ve simply got to KEEP your fuel clean.

I have been impressed with a piece of equipment-design that was “imposed” by a former owner. I have an old (1986) Ferguson 5-8B asphalt compactor/roller. It weighs 16K lbs and I use it to “mash” down and “level” a private turf runway that wild hogs occasionally dig up.
This equipment is stored outdoors without protection and has clearly always been. It is all-steel construction with faded, peeling paint and lots of rusted components. It’s fuel tank is a plain-steel “box”... very UNsophisticated and completely exposed to the weather and temperature cycles.
A John Deere 4239 4-cyl diesel serves for propulsion. That JD engine has all the fuel system filters, etc they typically have in whatever machines they are ordinarily installed... for example, it has that square-glass-filter element unique to JDs. And it has a pre-filter-filter as well.
But this compactor was first-owned by the state highway dept (TxDot) and they made, or had specified, certain additional protections for either safety or utility/longevity. (Maybe they have experience with uncaring operators?)

For example, the fuel tank has, besides it’s usual engine injector delivery/return lines, an additional circuit which is driven by an additional fuel pump which operates continuously, whenever the engine is running. It pulls fuel from the BOTTOM of the main tank and delivers it to a unique filter-assembly which has a settlement-tank incorporated, before returning the fuel back to the main tank. That settlement tank has a water-drain of it’s own, as well as an additional debris filter-element. The scrubbed fuel is then delivered back to the main tank...and continues to recirculate thru that secondary filtration system completely independent from the main engine system whenever the machine is running.

After servicing the main system filters I’ve found them to be cleaner than expected, while I’ve discovered water, rust, and junk in the secondary system filter/settlement tank. My conclusion is the secondary system was a great addition and showed foresight by TxDot for equipment they likely knew would have a tough life.

Thought I’d share in case anyone might find it useful.
 

D2Cat

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Geo, I have an '80's model Ditch Witch R-40 trencher with a Ford industrial gas engine. It has a steel fuel tank behind the seat. The tank has a sediment bowl with a shut off valve.

I took the line from the sediment bowl and added an inline filter and a 2 PSI pump after that filter. This machine sets out all the time. I can look in the sediment bowl and see the brown crud. I then remove and clean the bowel and replace the inline filter also. It starts and runs like a top, even after setting for weeks/months.

If an engine does not get clean fuel, it will let you know.... and usually at the most inopportune time.
 

El Tut

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Kubota 3901
Jan 30, 2021
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A cold engine will not regenerate. It has to be hot. Bernhardline is correct on most points but I would suggest full throttle instead of just 2000-2100. Just push the lever all the way forward and let it eat. It will not hurt anything.
And some engines do not get warm enough.....I am going round and round with the dealer right now on my new L3901 that runs forever and doesn't get warm enough. I covered the radiator up halfway which did bring the temp up a little but finally threw a wool blanket over the intakes on the cowl and the temp came up high enough to regen......should not have to do that.
 

DaveFromMi

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L3901 RCR1260
Apr 14, 2021
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Did anyone drive tractor when you were recovering? It is odd that the tractor would suddenly jump to needing a parked regen when you start it.

The automatic switching of the lights and the beginning of a regen won't happen until the tractor is warmed up... may require more time.

Tractor appears to be in PM warning level 2-2. Manual claims you can switch to auto regeneration. You don't have to drive it, it can remain stationary, but you do have to run the rpm up.

Do you have the old style regeneration inhibit switch? Does yours have a diagonal slash through it?

If you can't get it to regen, don't drive it!
I tried that step yesterday. Auto regen while stationary. Cranked the rpm up to about 2700 to get the rpm light to go off. Regen light still flashing after 20 minutes. Tractor was warmed up prior to this due to working. Auto regen failed, then parking regen light in dash started flashing. Got manual. Verified steps.1-->5 and 7. Hit inhibit switch (on), then again, off. Lamps still flashing. Eventually after some iterations I can't remember, the inhibit and parked regen switches started flashing. Getting somewhere finally. Hit inhibit, switch light off and parked regen (switch light stays on). Then successful parked regen including automatic rpm increase/decrease.

Questions:
1. Will parked regen only work if you have inhibit activated first?
2. If you try auto regen, stationary, and it is going to fail, do you just wait for the parked regen lamps/switches to start flashing?
Note: Mine is also an L3901. Has about 47 hours.
 

El Tut

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Kubota 3901
Jan 30, 2021
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Oxford, Maine
I tried that step yesterday. Auto regen while stationary. Cranked the rpm up to about 2700 to get the rpm light to go off. Regen light still flashing after 20 minutes. Tractor was warmed up prior to this due to working. Auto regen failed, then parking regen light in dash started flashing. Got manual. Verified steps.1-->5 and 7. Hit inhibit switch (on), then again, off. Lamps still flashing. Eventually after some iterations I can't remember, the inhibit and parked regen switches started flashing. Getting somewhere finally. Hit inhibit, switch light off and parked regen (switch light stays on). Then successful parked regen including automatic rpm increase/decrease.

Questions:
1. Will parked regen only work if you have inhibit activated first?
2. If you try auto regen, stationary, and it is going to fail, do you just wait for the parked regen lamps/switches to start flashing?
Note: Mine is also an L3901. Has about 47 hours.
Good questions and I don't have answers unfortunately. My scenario was almost exactly like yours except I got the red engine warning light and it wouldn't go off. Dealer came by and the tractor wasn't throwing any codes, they gave up then came back on put it on a flatbed and took it back to the dealership. They also thought it was a throttle positioner issue but it was not.....they were lost in my opinion. At the shop they went back to a regen problem and said that the tractor wasn't getting up to temp in order to regen. They drained the cooling system and filled it with straight antifreeze and said that would make it run hotter. A little sceptical on that one and I have always read that running straight antifreeze isn't advisable and how it makes it runner hotter is beyond me. At their direction I blocked the radiator about halfway and that pushed the temp up a little. This weekend I worked it hard and the regen light started blinking along with the light indicating that rpm needed to go up. I popped it up to around 2800rpm until the light went off and let it run. The regen light kept blinking indicating the regeneration hadn't started and I then went and got a wool blanket and covered all the intakes on the cowl. Six or seven minutes later it apparently got warm enough to regen and the regen light went solid. 15 or 20 minutes later the light went out and I assume the regen was completed. This whole ordeal is horse s&*^. No way a new $25,000+ tractor should run like this. There needs to be a fix. I wonder if the engine has a thermostat? This is like buying a new $50-60,000 pickup and having to block the radiator to get the heater to work.....like 50 years ago! I plan on keeping on bitching to the dealer until they come up with something that make sense and works!
 

sheepfarmer

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Good questions and I don't have answers unfortunately. My scenario was almost exactly like yours except I got the red engine warning light and it wouldn't go off. Dealer came by and the tractor wasn't throwing any codes, they gave up then came back on put it on a flatbed and took it back to the dealership. They also thought it was a throttle positioner issue but it was not.....they were lost in my opinion. At the shop they went back to a regen problem and said that the tractor wasn't getting up to temp in order to regen. They drained the cooling system and filled it with straight antifreeze and said that would make it run hotter. A little sceptical on that one and I have always read that running straight antifreeze isn't advisable and how it makes it runner hotter is beyond me. At their direction I blocked the radiator about halfway and that pushed the temp up a little. This weekend I worked it hard and the regen light started blinking along with the light indicating that rpm needed to go up. I popped it up to around 2800rpm until the light went off and let it run. The regen light kept blinking indicating the regeneration hadn't started and I then went and got a wool blanket and covered all the intakes on the cowl. Six or seven minutes later it apparently got warm enough to regen and the regen light went solid. 15 or 20 minutes later the light went out and I assume the regen was completed. This whole ordeal is horse s&*^. No way a new $25,000+ tractor should run like this. There needs to be a fix. I wonder if the engine has a thermostat? This is like buying a new $50-60,000 pickup and having to block the radiator to get the heater to work.....like 50 years ago! I plan on keeping on bitching to the dealer until they come up with something that make sense and works!
What was the air temperature? What did you do after upping the rpm? If you go on working it, it is better. Yours is not behaving typically.
 

El Tut

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Kubota 3901
Jan 30, 2021
4
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Oxford, Maine
What was the air temperature? What did you do after upping the rpm? If you go on working it, it is better. Yours is not behaving typically.
Around 60 degrees and yes I kept on working it. I have also been keeping the rpm's up around 2500 as the dealer recommended even though most of my tasks only require 2000.
 

sheepfarmer

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Around 60 degrees and yes I kept on working it. I have also been keeping the rpm's up around 2500 as the dealer recommended even though most of my tasks only require 2000.
I find it difficult to believe your engine couldn’t get warm enough at that temp. I wonder if there is a defective temp sensor? See what it does next regen. If not normal complain again to dealer.
 

DaveFromMi

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L3901 RCR1260
Apr 14, 2021
610
530
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Indiana
In order for parked regen to work, does it need to be in inhibit mode first?

On another note, I watched a video where a guy had a bad parking brake switch, which didn't allow parked regen to work. In the auto industry (retired Engineer here), if the severity of a problem was very high (leaves vehicle disabled), extra effort/cost was needed to prevent the failure or some failure mitigation was needed.
Seems too many things can cause the emission system to fail causing the tractor to be disabled.
While searching for Kubota parked regen info on the internet, a top hit was the highly questionable DPF CAN emulator (previous post).
 

jimh406

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I don’t know if it will help you, but I had a truck that wouldn’t go into Regen mode and complete. It would start, and then shutoff again.

My solution was to add an extreme amount of Diesel Kleen Summer version. I put two 80 oz containers into the tank. It was an extreme measure, but it was the weekend I needed to make it home. As you probably know, power is greatly reduced as the DPF is clogged. After a few miles, the Regen started and later completed. In any case, adding Cetane won’t hurt anything, but will make it burn hotter. Just an idea.