Turbocharging new L3940 Gutless Pig Tractor

[The Fred]

Instead of bashing my new powerless L3940 HST Cab tractor I would like to turbo the thing.

I see the same engine is used in the Bobcat S-160 skid steer with a turbo.

Rather than tell me why I don't want to do this can you throw me some ideas? Very serious here.

Thanks, Fred

 

[DT86]

Go order a replacement turbo for the skid steer online, you'll pay a little more since you don't have a core return. Next start hacking up the manifold, rerouteing the intake, welding, cussing and with a couple trips to the parts store you'll be in business.

 

[WilliamBos]

Will the fuel need to be turned up??



PLEASE do a thread on this for us, ok?

 

[nybirdman]

I know a guy that turbo charged a L3940,I don't know any of the details but I know it can be done.

 

[claridon]

Not an expert by any means but will the trans and axles take the additional power or will you end up chasing failures through the drive train?

 

[murphy1244]

Not an expert by any means but will the trans and axles take the additional power or will you end up chasing failures through the drive train?

Good question, could be more than you bargained for

 

[nybirdman]

I know somebody has got to ask....what are you doing where the tractor feels so underpowered?I had a L3130 HST that pulled a two bottow plow,pushed a six ft.snow plow ect.Traded for a L4240 mostly for the cab.I do most of my work with the L4240 in medium and toggle between high/low,this plus auto throttle I don't see how you can be underpowered.

 

[JerryG]

You will have to turn up the fuel pump unless the turbo is just set to break even. If you don't it will damage your engine.

 

[JasG]

There was a person who added a turbo to their Kubota several years ago and posted pictures here some where.

That being said the "newer" 40 series Kubota's are "emissions certified" and I don't believe you can turn the pump up. Which would mean you would have to change the fuel pump. As others have said, will the rest of the tractor take additional power?

It's probably more you are losing power from the HST. I have a L3240 and do regret not trying harder to find a L3540 with the GST. While I have good PTO power, the unit HST isn't as good at putting power to the ground. I have to do everything slower than an equal HP gear shift unit. I have read that you can lose as much as 35% of your power through an HST. So as much as 1/3 of any gain could be lost. I don't know what % the Kubota HST uses.

 

[MtnViewRanch]

Very common for the pistons to be different, the rods, injectors, injector pump and or settings. If you just put the turbo on without changing everything else that is suppose to be changed for that particular engine, you have just taken an engine that has a 100% duty rating and lowered that duty rating. How much depends on the engine itself. Really not a good idea if you work your tractor hard any length of time.

Just saying what you don't want to hear, but it is what it is. Can you do it and everything be good, maybe, but then there is a better than average chance that it pops.

Good luck

 

[DT86]

You will have to turn up the fuel pump unless the turbo is just set to break even. If you don't it will damage your engine.

Please explain. I'm lost on this one.

 

[pjbci]

Please explain. I'm lost on this one.

Me too!

 

[WilliamBos]

Please explain. I'm lost on this one.

It will run lean once you add a turbo, and will need more fuel, or it will blow up. Anytime you add more incoming air, you need more fuel.

Most of these pumps are mechanical on the compacts, should be able to turn it up.

Run it on a dyno to be safe afterwards.

 

[DT86]

It will run lean once you add a turbo, and will need more fuel, or it will blow up. Anytime you add more incoming air, you need more fuel.
.

What???? Please explain how this will cause the engine to "blow up"?

Unless you run it so lean that you put the fire out there are no problems from running a diesel lean. Even then it's just going to miss and sputter.


A lean gas motor will burn the pistons, a diesel no.

 

[WilliamBos]

What???? Please explain how this will cause the engine to "blow up"?

Unless you run it so lean that you put the fire out there are no problems from running a diesel lean. Even then it's just going to miss and sputter.

A lean gas motor will burn the pistons, a diesel no.

I tell you what, add a turbo to yours. You will find out first hand what happens.

 

[DT86]

I tell you what, add a turbo to yours. You will find out first hand what happens.

I have a turbo on mine thanks, bought it that way.

I played with diesel trucks through high school into my mid twenties. Not the tuners and chips kind of stuff, turbos, pumps and injectors kind of stuff. Read every diesel power magazine you ever heard of and a probably a few you haven't.

Now, if you'll bother to explain exactly what you think will happen I'll listen, but just saying it will "blow up" doesn't do for me.

I will agree adding a turbo with out fuel adjustments won't do much for the power department but running a diesel leaner will lower EGT's which can mean better economy.

...…Edit....

I realized that there was an incomplete thought pertaining to my playing with trucks and reading.

We've all heard of people blowing stuff up from too much fuel but never once have I heard of too little being a problem.

……That is all……

 

[MtnViewRanch]

Again, just my :2cents:. If the OP has power problems, sell the tractor and get one that will do what needs to be done. We ALL make mistakes, sometimes they are costly ones, (first hand experience here ) get what you need and move on. Now IF Kubota holds it's value like so many like to think, the OP should be able to get just about ALL of his money out of his tractor and get the one that he needs, don't you think. :confused3:

 

[DT86]

Again, just my :2cents:. If the OP has power problems, sell the tractor and get one that will do what needs to be done.

I agree I wouldn't start screwing around with a new tractor either.

 

[the old grind]

If there's no throttle plate and no air fuel ratio in a diesel, it seems a 'lean' condition will happen any time we're not churning out black smoke. :confused3:

Suppose a turbo increased BMEP at speed and thus demanded a tweak to injector timing that didn't happen. Over-pressure damage resembles that from running lean with petrol and gives rise to an unlikely concept/cause/label. just sayin' ...

 

[Loadstar]

If I was looking to do this I would start hunting for a potential donor turbo motor. Even just try to find a core turbo and maybe score a manifold.