Stalling an HST tractor

[flusher]

Stalling a diesel can cause a lot of problems--including reversing the engine rotation (engine runs backwards) with potential for major engine damage. Check this old TBN thread for details

http://www.tractorbynet.com/forums/john-deere-owning-operating/4698-diesel-running-backwards.html

 

[teg]

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.Mental note to self: Don't stall the engine, again...



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[k0ua]

I have got to say this.. I have never stalled my Hydro tractor (125 hours now). I can see stalling it when running the PTO.. but I don't see how to stall it thru the Hydro and wheel driveline.. I suppose if you put it in high and rammed a pile of dirt or gravel? I do 90 percent of my work in Low.. and this might be because of where I live on such hilly ground. When I had a Hydro New Holland I used mostly for mowing I used Med. Except for FEL work. But If I go into a pile that will not move (or a tree) the tires will still spin even with 750 lbs on the back and loaded tires or the Hydro pump will go into relief if the traction is superb. I have never had the motor bog down enough to even think about stalling. Tell me again how do you stall a Hydrostat equipped tractor? I truly don't understand. And did not think it possible.


James K0UA

 

[Redneck in training]

You can stall it when you run the engine at low RPM. The engine will start lugging before the relief valve opens or tires slip. If you keep RPM above 2000 it will work as you describe.

 

[k0ua]

You can stall it when you run the engine at low RPM. The engine will start lugging before the relief valve opens or tires slip. If you keep RPM above 2000 it will work as you describe.

Ok cool, I guess when I have come up to something that might not move I must have always gave it some fuel. Thanks

James K0UA

 

[KubotaToy]

I must have a good cranks in my tractors, I have stalled my B2710 and JD 6675 skid steer so many times (about half from my wife, does not like high RPM due to the noise) I am not able count them. Both running as good as the day I bought them. The B2710 is easy to stall no matter what rpm you are running if you try to get a bucket full of gravel, I have never been able to let off the trans pedal fast enough to recover once rpm drops when operating the FEL.

 

[orezok]

Interesting thought on keeping the RPM's up, but wouldn't the engine be at idle speed just before it stalls no matter what RPM it was operating at previously?

 

[RoyJackson]

Interesting thought on keeping the RPM's up, but wouldn't the engine be at idle speed just before it stalls no matter what RPM it was operating at previously?

No...a stall at a higher RPM doesn't reduce the engine speed to idle. The engine "dies" at the stall. Then it spins down (inertia) rapidly.

 

[LastSTRAW]

I am also confused. Wouldn't there be more force at play (and consequently more damage) from a high rpm stall? High RPM should make it harder to stall leading to few stalls over time which is good. But each time it does stall how would it be better for the tractor?

 

[RoyJackson]

I am also confused. Wouldn't there be more force at play (and consequently more damage) from a high rpm stall? High RPM should make it harder to stall leading to few stalls over time which is good. But each time it does stall how would it be better for the tractor?

Operating at a higher RPM (more torque and HP being produced) lessens the probability of stalling...doesn't prevent the possibility of stalling 100%, just much less likely to happen.
But yes, as there is more energy being produced, a stall at higher RPM could result in more damage to the engine.

I cannot ever recall stalling an engine at high RPM, but I have stalled more then a few at lower RPM. BTW, I'm not writing about tractors here...these were motor vehicles (mostly manual transmissioned trucks I wasn't familar with and mostly when first engaging a gear).