L2501 power upgrade

[Scott.vy1co]

This is a new thread In Relation to a previous hi rev power issue.

After some investigation and ultimately going yo the dealer, I was td by the dealer that Kubota has recognized the little mechanical pump on the l2501 is insufficient...at best it produces 1psi. The warranty repair is to now replace it with an electric pump mounted to the firewall...similar to the bigger L3901 etc. 7psi.

As well, while not an official kubota endorsement, the dealer said half the hard work is done to do the power increase if I wanted...simply adjust the fuel timing screw (in a non tamper cover) and power I crease would be significant. I have no plans to do that now, but after warranty ty it should not be hard to get it in to the low 30's for HP.

Just passing on as this is the first time I have heard it from Kubota.

Passed on for discussion only.

Happy tractoring

 

[lugbolt]

I asked Kubota about it (directly, at a training facility).

The official answer is something along these lines.

Tampering with it is getting into emissions stuff, thus Kubota and it's dealers are NOT to discuss this with ANYONE.

They wouldn't even hint at anything. They generally play on the safe side and always have.

One way to do it is increase the torque it makes at the same rpm. The right way to increase HP is to increase the rpm and you probably don't want to increase that; as the pto will run way too fast, the tractors travel speed will run too fast the pumps will run faster, etc.

that said I did my own research at one point, comparing the various engine submodels and found the differences. It's pretty simple but it's also requiring a lot of work to get it done. Upper 30's isn't impossible, maybe 40. But again you're going to run into a lot of other issues. If you bought all the stuff new, I was seeing about $2200 worth of stuff....which I'm not sure is feasible. Mind you that was about 2016...probably $4000 now.

what you're describing is pouring more fuel to it which will also increase combustion temps and EGT. It's designed to ingest so much air, burn it, and exhaust it....so without KNOWING for sure what an increase in EGT would do, I can't say whether it's a good idea...or a bad one. Maybe you can be the guinea pig and try it?

 

[Roadworthy]

That's good information to have and I know the tractor is rated conservatively. Even so mine has sufficient power and doesn't need the stress of trying to put out more. If I needed more power I'd probably shop for a heavier tractor, too.

 

[Scott.vy1co]

That's good information to have and I know the tractor is rated conservatively. Even so mine has sufficient power and doesn't need the stress of trying to put out more. If I needed more power I'd probably shop for a heavier tractor, too.

I agree...I am just happy to have the sputtering gone. The little 2501 is a beast znd dies all I need it to do...nice it could do mire, but fir now it's fine.

 

[Rdrcr]

You may be able to gain some additional power from the D1703 by simply adjusting the fuel set screw but, in order to make a substantial gain in power, you’ll need to advance the injection pump timing and that’s a much more involved process, but entirely possible.

Mike

 

[Rdrcr]

Or, you can throw caution to the wind and add a Turbo to the L2501 for a substantial gain in power;

Mike

 

[Cathy Liebchen]

This is a new thread In Relation to a previous hi rev power issue.

After some investigation and ultimately going yo the dealer, I was td by the dealer that Kubota has recognized the little mechanical pump on the l2501 is insufficient...at best it produces 1psi. The warranty repair is to now replace it with an electric pump mounted to the firewall...similar to the bigger L3901 etc. 7psi.

As well, while not an official kubota endorsement, the dealer said half the hard work is done to do the power increase if I wanted...simply adjust the fuel timing screw (in a non tamper cover) and power I crease would be significant. I have no plans to do that now, but after warranty ty it should not be hard to get it in to the low 30's for HP.

Just passing on as this is the first time I have heard it from Kubota.

Passed on for discussion only.

Happy tractoring

 

[Cathy Liebchen]

The power upgrade is replace it with a 3901/2

 

[Rdrcr]

The power upgrade is replace it with a 3901/2

That’s an option.
But, an expensive solution.

The Kubota L3901 produces 37.5 HP and delivers 30.6 PTO HP. This tractor makes 34% more power and is $4,734 more expensive than the L2501.

The Kubota L3902 produces 37.5 HP and delivers 30.3 PTO HP. This tractor makes 34% more power and is $6,987 more expensive than the L2501.

An L2501 modified with an Injection Pump timing advancement and additional fuel will produce roughly 31 HP and 25 PTO HP. That’s a 20% increase in power…for FREE!

And, an L2501 equipped with Turbo setup, making only 4 PSI of boost pressure will produce roughly 38 HP and deliver 31 PTO HP. That’s 35% more power than stock for around $2,500 (more power can be made by increasing boost pressure and adding additional fuel). That’s a TON cheaper than upgrading to an L3901/3902.

Mike

 

[whitetiger]

Just passing on as this is the first time I have heard it from Kubota.

You did not hear anything from Kubota, you had an employee from an independent Kubota dealership giving you their personal modification and opinion.

 

[Rdrcr]

^^^^^
Indeed.

I wouldn’t mind learning more about this fuel pump….mounting location, part number and installation…

I’d also like to know why the factory fuel system failed.

Mike

 

[Scott.vy1co]

You did not hear anything from Kubota, you had an employee from an independent Kubota dealership giving you their personal modification and opinion.

Thanks for your thoughts on this and what you thought I heard. The dealer reached out to Kubota who advised them they are seeing more and more of these issues under warranty and for the past year have been recommending this mod with the fuel supply system. Thanks, Scott.

 

[Rdrcr]

^^^^
I'm pretty sure whitetiger is a Kubota technician working for a dealership. Perhaps, he hasn't seen any official bulletins from Kubota authorizing this specific fix?

I haven't experienced any fueling issues with my L2501....and I have my fuel turned up for my Turbo system. But, thank you for bringing up the topic...just in case I run into some issues in the future. I would just like some additional information, like the part number(s) for the replacement fuel pump and installation procedure.

Mike

 

[lugbolt]

Or, you can throw caution to the wind and add a Turbo to the L2501 for a substantial gain in power;
View attachment 88374
Mike

what is your PTO power? What is your EGT under max power?

 

[Mark_BX25D]

what you're describing is pouring more fuel to it which will also increase combustion temps and EGT. It's designed to ingest so much air, burn it, and exhaust it....so without KNOWING for sure what an increase in EGT would do, I can't say whether it's a good idea...or a bad one. Maybe you can be the guinea pig and try it?

Two thoughts. Okay, three.

1. People have been powering up diesels by nothing more than adjusting the fuel for a long time now. It has its limits, but it works.
2. An EGT is never a bad idea if you are going to tweak the fuel.
3. If it will take a turbo without blowing up, it will surely take a bit more fuel without blowing up. The trick is in knowing the limits (so see #2).

 

[Rdrcr]

what is your PTO power? What is your EGT under max power?

L2501 Turbo: A Journey Defined - The tractor, The comparison, The modification, The results...

Part 1: Background The purpose of this thread is to share the concept, creation, progress and performance of my custom Turbocharged Kubota L2501 HST 4WD tractor. I’ll start by offering my opinions on this tractor, why I bought it, how it’s performed, the advantages and disadvantages, and why I...

www.orangetractortalks.com

Post #6 and continued on post #22.

Mike

 

[lugbolt]

L2501 Turbo: A Journey Defined - The tractor, The comparison, The modification, The results...

Part 1: Background The purpose of this thread is to share the concept, creation, progress and performance of my custom Turbocharged Kubota L2501 HST 4WD tractor. I’ll start by offering my opinions on this tractor, why I bought it, how it’s performed, the advantages and disadvantages, and why I...

www.orangetractortalks.com

Post #6 and continued on post #22.

Mike

so you are selling them? Are you a company? Vendor?

 

[GreensvilleJay]

curious ...
If you increase the power of the engine, will the rest of the drivetrain handle the extra power ( torque) ??

I've seen splined axles turned into 'bars' when others upped the engine HP.

 

[rancher1524]

Simple solution, buy a bigger tractor.

 

[tractorX]

^^^^^
Indeed.

I wouldn’t mind learning more about this fuel pump….mounting location, part number and installation…

I’d also like to know why the factory fuel system failed.

Mike

this is my next mod (will turbo eventually) on my l2501.
a good friend (owned and raced high performance diesel trucks) told me, the mod isn't complete until i take the pump, pipes and injectors to a diesel pump specialist for tuning. i found one of the best in the nation bout 1.5 away. when i get time this winter i'll pull it and run it over. ill keep you posted.

OP, i have advanced the timing and fuel on my l2501, BIG difference in performance! the l2501 uses the D1703 engine, detuned from 37HP to 24.8HP to meet tier 4 regulations.
~50hrs of hard dirty excavation and clearing since the mod... it just wants more!
check this out, great info on the D1703 engine

L2501 Modifications

Hey Guys new to this forum. I own a performance shop and I build turbo kits. I started in the diesel world with a 4bt swapped 47 Chevy currently making 600whp 950 tq on 70 psi. I also build custom turbo kits for bmw platforms. I purchased 5 acres of property and jumped on buying an l2501 HST...

www.orangetractortalks.com