L3400 running backwards !

[Chilly807]

Chilly807,, I bet you could not duplicate it if you tried, you must have let off of the winch control, at just the exact time the engine stalled, but had a compression stroke at TDC and then pushed it backwards, but now with no load it sputtered back to life. running backwards.. I bet you can't make that happen again in a million years.

James K0UA

I think you're right, James. All the planets were aligned and I held my mouth just the right way. Lucky I didn't get hit by a falling meteorite at the same time.

Doesn't seem to have had any adverse effects on the old girl, I pulled another 50 or so alder clumps this evening, this time with the rpm at about 1200. No problems. Tomorrow we're digging fence post holes, and Sunday looks like a 12 acre field to brush hog if the weather holds. Fast running out of days I can get on the fields without leaving ruts.

Sean

 

[Chilly807]

When I was a young teen, I watched my neighbor doing some FEL work with his Deutz, about a 50hp 4 cylinder. He was working it real hard and managed to *just* about kill it. When he clutched it, it sounded different. The muffler rain cap slammed down and hissed like crazy from the vacuum. He shut it off and hit the key and resumed his work.

The mechanical injectors probably are just a tad late to have it fire well, but it still ran just fine that way with a slightly slower rpm. I know that tractor was still running fine 30 years later.

Pretty much what I was thinking Ray

 

[Gordon Gould]

I am wondering if the tightly stretch cable helped to give it a spin the other way when it stalled. Or maybe the pto mechanics don't work that way

 

[LD1]

I am wondering if the tightly stretch cable helped to give it a spin the other way when it stalled. Or maybe the pto mechanics don't work that way

The PTO has an internal ORC, so that shouldnt have had an effect.

I think if he had not dis-engaged the winch, the tractor would have just stalled??? maybe??

 

[Chilly807]

I am wondering if the tightly stretch cable helped to give it a spin the other way when it stalled. Or maybe the pto mechanics don't work that way

Good point, I think you may be right about that..

 

[Chilly807]

The PTO has an internal ORC, so that shouldnt have had an effect.

I think if he had not dis-engaged the winch, the tractor would have just stalled??? maybe??

Mine doesn't have that, only the HST models do. And you're right, I've stalled it once before, but that was with a lot heavier load and at a higher rpm to start with.

 

[Chilly807]

Good point, I think you may be right about that..

On second thought, maybe not.. once the winch rope was released it freed the winch from the PTO so the cable would have just gone slack, which it did.

 

[LD1]

I think you do have an orc. I thought all 3400's regardless of wether hst or gst had an orc.

I could be wrong, maybe just the fact that its an independent PTO is why I am thinking. Since it dont push you along when bushhogging and hit the clutch???

 

[LD1]

I think you do have an orc. I thought all 3400's regardless of wether hst or gst had an orc.

I could be wrong, maybe just the fact that its an independent PTO is why I am thinking. Since it dont push you along when bushhogging and hit the clutch???

 

[JasG]

I didn't know this was possible with a 4 stroke engine. It was very common with the old detroit diesel 2 strokes though. Stall the engine and have the load/force get the engine spinning the wrong way and it would happen. My dad has seen it happen with machinery and trucks using the old 2 strokes.

 

[Chilly807]

The HST models have the ORC to protect the transmission from being driven by the implement, the DT models like mine have a 2 stage clutch so it's not an issue. When I push the clutch in halfway, the engine acts as a brake to slow down the implement while allowing the wheels to turn freely. It's most noticeable with the rotary cutter, which has a lot of inertia. If I had the ORC there would be a clicking noise as the pawls ratcheted from the cutter driving the clutch. Instead there's just a whine as the engine slows the cutter down.

Sean

 

[Chilly807]

I didn't know this was possible with a 4 stroke engine. It was very common with the old detroit diesel 2 strokes though. Stall the engine and have the load/force get the engine spinning the wrong way and it would happen. My dad has seen it happen with machinery and trucks using the old 2 strokes.

Yeah, the muffler acts as an air filter, and the air cleaner gets turned into a muffler.. doing this once will be enough for me. Intake valves and exhaust valves switch roles, the whole shebang.

Sean

 

[chim]

When I was a kid fresh out of high school I worked at a quarry. I picked the wrong gear one day and the Euclid stalled out on a hill. Although I didn't heed the advice to gear down, I did remember being told to NEVER shift or take it out of gear on a hill. Next thing the "Yuke" coasted backward and the engine started up again and sounded wierd. The truck was equipped with an oil-bath air cleaner and it spewed oil on the fender. It didn't appear to hurt anything and the older guys laughed and told me "That happens. Next time use granny gear".

 

[Gordon Gould]

The way I see it it is not Over Running. It is pulling back the other way and I thought it should be a solid connection to the motor thru the pto ??? I am thinking you probably didn't drop the rope until after it stalled. Just a thought.

 

[Chilly807]

The way I see it it is not Over Running. It is pulling back the other way and I thought it should be a solid connection to the motor thru the pto ??? I am thinking you probably didn't drop the rope until after it stalled. Just a thought.

Yeah... that would do it, if the engine wasn't making power anymore, the cable WOULD pull it back the other way.. could very well be.

 

[LD1]

This is going to make me check my 3400 when I get home. I could of swore it had an ORC:confused2: But no biggy if it dont.

Anyone who has a L3400 GST and is off today.....with the tractor off, engage the PTO lever and see if you can turn the PTO shaft by hand in either direction....

 

[JasG]

This is going to make me check my 3400 when I get home. I could of swore it had an ORC:confused2: But no biggy if it dont.

Anyone who has a L3400 GST and is off today.....with the tractor off, engage the PTO lever and see if you can turn the PTO shaft by hand in either direction....

I doubt you can, most tractors I have run if I throttle down fast the tractor will act like a brake slowing down things like a brush mower.

 

[ccsial]

A crank position sensor probably wouldn't pick up on it. For any sensor to pick up on direction of rotation it needs two pickups and two tone wheels that are offset from each other. Tat way the computer would see two signals and can be programed to look for the space between the two pulses. With just one all the computer would know is that the shaft is turning and that it's still timed correctly with the crank shaft. Engineers just assume the engine will not run in reverse so they don't have to install a more expensive sensor set up.

Some engines use Hall sensors that can pick up direction and absolute position.

 

[mattridessleds]

I've had my L2800 do this once when I was moving some dirt. Stalled out and then started running in reverse. Shut the key off right away. I've also heard of the old 2 strokes doing it. I was pushing into a pile so once it stalled I think there was just enough force to move the tractor backwards while my foot was still on the pedal to get it to spin the other way.