L5240 or 5740 HP vs fuel consumption?

[dbk123]

Hi,

I'm considering purchase of an L5240 or L5740. The most demanding use in terms of HP requirements will doing brush hogging some rather steep pastures with fairly thick grasses using a 6 foot rotary cutter. This will done in the summer with AC running in the cab.

I'm trying to determine whether I'm better off with 45 or 50 pto HP for this application and trying to determine how the fuel economy might differ between the 45 HP tractor working harder or the 50 HP tractor running a bit easier.

I understand that the method used to get the additional HP from the L5740 involves "turning up the fuel flow".

Any information greatly appreciated.

Thanks,

-dbk123

 

[curtisfarmer]

The added HP will greatly outweigh the fuel savings of only a marginally smaller engine in the long run. 5 more hp. is worth more than saving $4 every 8 running hours.

Just my 2 cents.

 

[hayden]

I think you will find the fuel consumption to be very close between the two machines. Unlike gas engines which have a very non-linear comsumption to output profile, diesels are much more linear. This means fuel consumption is more closely proportional to power output. If it takes something like 35 HP to mow and cool the cab, both engines will consume about the same fuel to generate that 35HP. I'd go with the larger tractor.

 

[hayden]

I just remembered that the L5240 and 5740 have the same engine, so I don't see any way there would be a fuel consuption difference at any load at or below the 5240's max.

 

[curtisfarmer]

I believe the L50's have the same motor, but offer non turbo(L5040) and turbo models, and only increase the rpm rating to achieve the desired output. I think there would be a measurable difference due to these factors, but we are talking about amounts that are so small they really don't mattter. Go with the bigger HP machine for sure.

 

[john_bud]

In some cases the smaller engine will actually use more fuel. When engines are at the 100% max output, the economy often is not as great as when they are opertating at 75% of max.

For your stuff, the larger one would be my choice.

jb

 

[art]

Onr good thing about an injection pump vs the carburator is the injection pump is a variable sized hole! If your not calling for it, it's not going to send it so a diesel can run very economical to a degree. The biggest difference would be under higher load condions where the lower horsepower might be over taxed which might burn far more fuel then a larger engine running easily.

 

[Double Orange]

I run my 5240 Cab
at 2250 RRR's powering a 72'' RFM. She'll burn 1.5 gph.

 

[Bob_Young]

What Double Orange just reported for his 72" RFM, is almost precisely what my old Ford 4000 burns turning a 72" brush cutter and also what my L4300 burns running the same implement. Unless seriously undersized or oversized for the job, a diesel just burns what's needed to get the work done. Much different than a gasser.
Bob