Yanmar 424 low power and comparisation with Kubota

[rScotty]

Noticed the Yanmar 424 engine is HP rated at 3200 RPM. Kind of high. If the brake wasn't set were the engine RPMs high enough? A mid mount mower is fine if you keep up with mowing. You are always limited with how high these can be raised in any brand and if you use the tractor for tasks other than mowing a lot it seems they are always in the way. I had a drive over deck but found getting it on and off still a major PIA. 3pt quick hitch I liked better. Deere looks like nice mid mower connect is this also on Yanmar?. If the grass get a little high a good rear discharge 3pt finish mower performs much better and gives a greater range of heights. 1800 pounds is not too heavy for gardening. Do not load the tires for weight if using on lawns and gardens mainly.
As for engine RPMs my Kubota of similar size is HP rated at only 2500 RPMs. Less RPMs equals less wear and greater engine life.

All good points - or at least I think so because they are points I agree with. So if we are wrong we are wrong together.
I don't use a mid-mount mower myself for all the reasons you mention. And of course less RPMs equals less wear.

On the other hand, Yanmar is one of the world leaders in all phases of diesel engines. Most marine diesels are Yanmar = all the way up to super tankers.
It's a company that melts their ore and does their own iron castings so that they have control over all phases of production. For Yanmar, tractors are a sideline. They maybe make a little money but just as important is the whole agriculture/aquaculture social responsibility - that's big in Japan. And reliability is real important to them nationally as well. So when I see Yanmar doing something at a different RPM or with a whole different type of transmission like their new I-HMT.... well, that's when I take a second look.

After all, back in the 1970s they invented the front axle that is used today on all 4wd tractors. I was around for that, and remember being skeptical.
rScotty

 

[maciek8791]

All good points - or at least I think so because they are points I agree with. So if we are wrong we are wrong together.
I don't use a mid-mount mower myself for all the reasons you mention. And of course less RPMs equals less wear.

On the other hand, Yanmar is one of the world leaders in all phases of diesel engines. Most marine diesels are Yanmar = all the way up to super tankers.
It's a company that melts their ore and does their own iron castings so that they have control over all phases of production. For Yanmar, tractors are a sideline. They maybe make a little money but just as important is the whole agriculture/aquaculture social responsibility - that's big in Japan. And reliability is real important to them nationally as well. So when I see Yanmar doing something at a different RPM or with a whole different type of transmission like their new I-HMT.... well, that's when I take a second look.

After all, back in the 1970s they invented the front axle that is used today on all 4wd tractors. I was around for that, and remember being skeptical.
rScotty

This is all correct. However today I made 2 hours trip to see and drive Kubota b2 series 2018' , 2231 model with 23HP.
This one had 3-point hydrostatic transmission vs 2-point which Yanmar has, but no FEL.

Well I was literally blown away by the Kubota speed and agaility. This is something completly different, like You switch from a school bus to a racing car. But I noticed something very interesting : if You switch this Kubota into Highest mode to get max speed, You do not have to increase RPMS. The tractor is going very fast, but no need to increase RPM, the lever remains on low, seller explained that this is the new feature of this model. On Yanmar presentation the guy from Yanmar asked me to increase RPM into max, before going fast - I had to do it manually. Was it correct? Maybe it was a mistake, to increase RPM manually on Yanmar, because Yanmar has the same feature? Because if this is the difference, that with Kubota I simply press the pedal without adjusting RPM, I must say it's a good adventage.

Frankly speaking it will be hard now to come back to Yanmar.

best regards M.

 

[rScotty]

This is all correct. However today I made 2 hours trip to see and drive model with 23HP.
This one had 3-point hydrostatic transmission vs 2-point which Yanmar has, but no FEL. Kubota b2 series 2018' , 2231

Well I was literally blown away by the Kubota speed and agaility. This is something completly different, like You switch from a school bus to a racing car. But I noticed something very interesting : if You switch this Kubota into Highest mode to get max speed, You do not have to increase RPMS. The tractor is going very fast, but no need to increase RPM, the lever remains on low, seller explained that this is the new feature of this model. On Yanmar presentation the guy from Yanmar asked me to increase RPM into max, before going fast - I had to do it manually. Was it correct? Maybe it was a mistake, to increase RPM manually on Yanmar, because Yanmar has the same feature? Because if this is the difference, that with Kubota I simply press the pedal without adjusting RPM, I must say it's a good adventage.

Frankly speaking it will be hard now to come back to Yanmar.

best regards M.

I'm needing some clarification. With some older forms of HST - common a decade ago - you would set the throttle for engine RPM, and then work the HST foot pedal to regulate how the HST transmission. You were essentially regulating the gear ratio of the HST. So you would advance the throttle real high if you wanted to move the HST pedal into a higher gear ratio....i.e. go faster over the ground.

If you were only going to go slow by just pushing down a little on the HST pedal then you didn't need as much throttle. No need for the engine to be roaring when you are just piddling along. So it was always a balance between how you manually set the throttle lever and how far you manually pushed down on the HST pedal.

But today most tractors have some version of "auto-throttle". It may be that the " Kubota b2 series 2018' , 2231" just got upgraded to auto-throttle. I'm afraid that I thought before that all those tractors already had it. It was pretty common back about 10 years ago. And maybe they do? We both should look at the specs to see. With auto-throttle the engine basically runs at a normal idle until you push the HST pedal down at which time the throttle is automatically advanced to meet the demands of the gearing and the speed desired. You never touch an independent engine throttle unless you want to do so. With auto-throttle when you want to slow down, reduce pressure on the HST pedal and the engine RPMs automatically fall. Remove any pressure from the HST pedal and the RPMs return to idle.

With auto-throttle there is a manual override throttle that you can use if you want to turn off auto-throttle on the dash & step back into your oldster time machine But it's real reason for the manual override is for when you are doing PTO work. With PTO work you do want control over the engine RPM to be independent of ground speed. For example, you may want to use the PTO to run a PTO pump to pump out a pond. Then the tractor just sits there for all day running a pump. No speed at all, but you do want the RPM to be up.

Is any of this sounding familiar? I'd better go look at the specs on those two tractor and will after the town meeting tonight.

Sounds like Yanmar may be going down to defeat here.... Well, we've got a Kubota too..... with auto-throttle & auto return to idle.
Great Pumpkin!
rScotty