Stalling an HST tractor

[SPYDERLK]

Perhaps you missed the point. A stall occurs when load exceeds power available at any RPM thereby reducing the RPM to a point where combustion cannot be continued (0 RPM). At some point along that curve, the RPM will be at idle RPM and the engine will be fueling and producing power.

Doesn't matter much where the RPM's start, it will pass through idle range at some point.

Yes. There is a difference tho, particularly on a direct drive/clutch transmission. NO slippage is available beyond the wheels. If they "stop" at hi rpm drive the engine stops in virtually the same time as a lo rpm stop under the same condition. Theres a lot of energy stored in the fast spinning mass. Taking it out quickly is very hi stress. ... With HST the internal pressure relief should crack, allowing a few extra revolutions and give a more gentle stall.
larry

 

[Chain Bender]

Got my tractor back yesterday with a completely new engine. They siad to run it with a lot of rpms, even at PTO rpms and higher just to putt around in the yard without a load. Brought it home and unloaded it. Boy did it sound good. Ran it on up to 2500 and I can now say that the original engine never sounded as smooth as this one. Never.

I also have to tip my hat to Kubota for their warranty policies. They and Sowell Tractor in Panama City, Fl have really been good to me.

cheers,
CB

 

[powerpace]

Got my tractor back yesterday with a completely new engine. They siad to run it with a lot of rpms, even at PTO rpms and higher just to putt around in the yard without a load. Brought it home and unloaded it. Boy did it sound good. Ran it on up to 2500 and I can now say that the original engine never sounded as smooth as this one. Never.

I also have to tip my hat to Kubota for their warranty policies. They and Sowell Tractor in Panama City, Fl have really been good to me.

cheers,
CB

I've posted this before.
When I bought my first Kubota back in 1973 it was one of the first sold in my area (Salem, OR). With about 400 hours the engine failed. Kubota bought my engine from me and replaced it with a new one. They had never had a failure till that time.

 

[Don87]

Got my tractor back yesterday with a completely new engine. They siad to run it with a lot of rpms, even at PTO rpms and higher just to putt around in the yard without a load. Brought it home and unloaded it. Boy did it sound good. Ran it on up to 2500 and I can now say that the original engine never sounded as smooth as this one. Never.

I also have to tip my hat to Kubota for their warranty policies. They and Sowell Tractor in Panama City, Fl have really been good to me.

cheers,
CB

Glad to hear they took care of it for you, and yes.......proper break-in according to my manual is full throttle usage, even with no load situations. Otherwise you will end up with a 'weak' engine after the break-in period.

 

[willi67]

The manual for my Kubota (BX2360) says not to use full throttle especially during break in ... it gives the impression that you should "baby" a new tractor. I use mine for mowing steep hills and run it at 2800-3000rpm in low range .. got 40 hrs so far
Seems like some are running at low RPM and flooring the HST pedal to go faster or to get more power .. did it myself before I read this site

 

[Don87]

The manual for my Kubota (BX2360) says not to use full throttle especially during break in ... it gives the impression that you should "baby" a new tractor. I use mine for mowing steep hills and run it at 2800-3000rpm in low range .. got 40 hrs so far
Seems like some are running at low RPM and flooring the HST pedal to go faster or to get more power .. did it myself before I read this site

That's extremely odd.
Maybe Kubota engines are just that much different from Iseki, mine just said not to put heavy loads on the tractor during break-in.

 

[MHarryE]

Definitely a broken crank

Kubota dealer called me Tuesday to let me know the crank was broken and had cause so much internal damage that Kubota is going to replace it rather than repair it.

Kubota is great when it comes to warranty work.:thumbsup:

Chain Bender

That's great. At this time of year I had problems with some dealers wanting to rebuild rather than replace for major damage like this because shops can be slow in winter and they want the work even if the customer and company come out on the short end of the stick. I was told I thought too much like a customer because of my replace rather than rebuild attitude.

 

[Gary Fowler]

There are some very different break-in specs coming from folks with sometimes same brand tractors.
My LS said to run it under full load for break in. I didnt have any equipment that could fully load it, but did manage to keep the motor loaded down digging my pond with the FEL and box blade. I have never seen a tractor manual that said to baby the engine for 40 hours.
I can tell you for a fact that never will you find a farm tractor that is "babied" for more than 10 minutes for warm up only. Most dealers when bringing out a new tractor for demo will hook it up with the biggest, baddest implement that they have to show the new owner just how well it pulls.

Outboard boat engines are about the only thing I have seen that have a long break in period and even those tell you to run them up full throttle for about 5minutes then throttle back to 75% power for a period of time then back up briefly during their 40 hour break in period. They dont want you droning on and on at the same RPM for long periods.

 

[Chain Bender]

When I picked up the tractor he said the new engine was running just fine. Said the mechaninc had it running at PTO speed (2500 rpms) just outside of his office for over an hour the day before???

CB

 

[willi67]

yep, that's what my BX2360 manual says as well, but the mower manual says to run at full throttle .. so what do you do with a new engine/tractor?
I have run mine between 2800 and WOT since new under load, mowing tall grass.

Great news that Kubota have come up with a new engine !