Lawn Care Forum banner

Diesel Zero Turn

6K views 13 replies 7 participants last post by  GMLC 
#1 ·
Wondering what information I can get on diesel mowers. I am looking at 3 new Gravely 460's with the 25 Kubota engine. Priced at 11,700. each seems very competitive. I have been running 27 kohler gas engines for a long time and after about 2000hrs they need replacing. How many hours are you guys seeing and just as important how much fuel do these engines use per hour? I have heard people say anywhere from 1/4 to 1-1/2 gallons per hour. Guessing that somewhere in the middle is accurate. Any pros or cons you have experienced? How about overall thoughts on the Gravely 460 machine?
Thanks
 
#2 ·
I have been running my Gravely 400 series going on two seasons now. IMO it has the best combination of comfort, cut, and quality in the industry. It is the machine that has set the bar. Mine is not diesel but I have run Kubota diesels with over 5000 hours which averaged 1 GPH.

I have a huge review on my 452 if you want more detailed info on the 400 series.
Posted via Mobile Device
 
#6 ·
Demo the exact mower you want to buy! I tried a 60" diesel last week. It didn't like the hills, or wet grass. Night and day difference between the gasser, and the diesel.
If I understand you correctly, you're saying it didn't like hills or wet grass- as in being on wet grass? Or did you mean it didn't cut wet grass well?

And yes, who's machines are we talking about here?
 
#7 ·
I run the kubota zd326. I have the 26hp diesel and I'm pushing a lot larger machine. I average 1gph cutting the worse grass working the engine for all she has. So far 0 issues with 1100 hrs. I have another 1800 hrs on my diesel grasshopper and no issues. I call false on the hills. I have never had a mower out do this kubota on a hill. It will not slide period unless the grass is wet, then any turn tire will. Some of the grasshopper guys on here are getting over 9000 hrs. These engines are 6000hrs before they expect an overhaul. You could see 10000-12000 hrs before an overhaul if you treat it well and I've gravely has its cooling system right. No real cons except weight, pro's are toque, fuel, life, and over lower maintenance.
Posted via Mobile Device
 
#9 ·
If I understand you correctly, you're saying it didn't like hills or wet grass- as in being on wet grass? Or did you mean it didn't cut wet grass well?

And yes, who's machines are we talking about here?
I believe he demoed a gas 400 series and a diesel 400 series. For some reason the diesel didnt perform like the gas. I dont understand why that is yet?
Posted via Mobile Device
 
#11 ·
OK, thanks.

I don't understand it either then, and would like to hear more about it.
I do know unless they change the frame a diesels sits high in the frame if your converting from gas. A diesel motor is abbout 3 ft tall and its weaviest at the top. My grasshopper and kubota the engine sits less than 6 inches off the ground and all of the machine weight is less than waist high. I don't think you would get that in gravely with a diesel.
Posted via Mobile Device
 
#12 ·
Sorry boys, It's been a long week. DSLS was asking about a Gravely 460 diesel, that is what I demo'ed last week. I also took a 460 gasser out for a demo earlier this summer. The diesel version is slower, and very weak when climbing a hill. It had a hard time climbing the hill and mowing at the same time. It was fine going down the hill. I think the problem is the smaller, but heavier motor, and transmission combo. The Gravely rep believed that all diesels do this. That I didn't agree with. This mower did a sloppy job cutting wet grass from 4" down to 3.25". It left a lot clippings. I don't know if any other mower would have done a better job. Like the rep said, "What did you expect? The grass is still wet."
 
#13 ·
Sorry boys, It's been a long week. DSLS was asking about a Gravely 460 diesel, that is what I demo'ed last week. I also took a 460 gasser out for a demo earlier this summer. The diesel version is slower, and very weak when climbing a hill. It had a hard time climbing the hill and mowing at the same time. It was fine going down the hill. I think the problem is the smaller, but heavier motor, and transmission combo. The Gravely rep believed that all diesels do this. That I didn't agree with. This mower did a sloppy job cutting wet grass from 4" down to 3.25". It left a lot clippings. I don't know if any other mower would have done a better job. Like the rep said, "What did you expect? The grass is still wet."
Definitely something wrong there. Diesels are known for their torque, and while they may lug down some under load (like going up a hill) they only do so to a point because that's how they are designed and when their torque skyrockets, and will then keep on chugging along long after a gas engine gives up and stalls.

The QOC shouldn't change just because one is diesel and one is gas unless the manu doesn't change the pulley set up to accommodate the diesel's lower engine rpm's at operating speeds. I've owned several diesel compact tractors ranging from 21 hp to 40 hp, and there is no gas engine machine in the same class with any of them that will do what they can do.
 
#14 ·
Definitely something wrong there. Diesels are known for their torque, and while they may lug down some under load (like going up a hill) they only do so to a point because that's how they are designed and when their torque skyrockets, and will then keep on chugging along long after a gas engine gives up and stalls.

The QOC shouldn't change just because one is diesel and one is gas unless the manu doesn't change the pulley set up to accommodate the diesel's lower engine rpm's at operating speeds. I've owned several diesel compact tractors ranging from 21 hp to 40 hp, and there is no gas engine machine in the same class with any of them that will do what they can do.
Ridin' I think your on to something. If the deck and hydro pulleys are the same size as the gas version this could cause both problems. The diesel runs at a lower rpm like you said.
Posted via Mobile Device
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top