L3400 running backwards !

[Chilly807]

Big reversing diesels were once common on ships. For all I know, they may still be

That's true.. I work on marine diesels, and I'd heard of those although I've never seen one. Apparently they had/have a lever which repositions the camshafts to allow the engine to run in the opposite rotation. And I would think the oil pump has a check valve system to produce oil pressure in either direction.

Sean

 

[Chilly807]

Wow, Sean, that is a first that I have heard of for a 'bota. Man, that can't be a "good thing", bound to have put a few "hours" on the bearings and other lubricated parts.

James K0UA

Yeah, that's what I was thinking too. I'm glad it wasn't running any faster and the engine was warm at the time. I remember reading something like this a long time ago, no oil pressure was the real clue for me.

Sean

 

[Gordon Gould]

I guess I won't do that any more with my winch. Sometimes when I have a lazy pull or want to go slow because it works better like pulling up brush I leave it at idle. I doubt that I would be to quick figureing what was happening. Glad you didn't waste any time getting it shut down.

 

[Chilly807]

I guess I won't do that any more with my winch. Sometimes when I have a lazy pull or want to go slow because it works better like pulling up brush I leave it at idle. I doubt that I would be to quick figureing what was happening. Glad you didn't waste any time getting it shut down.

One question the dealer asked me was if the winch would slip before the engine stalled. Normally it will if I run at a higher speed, since there's more power available. At idle, the engine doesn't make enough power to slip the clutch in the winch. I like the slower pull at idle for small jobs, but I don't think it's the best approach if the load gets hung up as it did in my case.

The same thing could happen using the loader if you dug into a pile and almost stalled the engine. I just happened to hit the perfect conditions to have it occur.

Sean

 

[czechsonofagun]

The only time I saw it happen was on an old Jawa 2 stroke motorcycle.

 

[Chilly807]

The only time I saw it happen was on an old Jawa 2 stroke motorcycle.

Now that would be interesting.. I can imagine giving it a shot of gas and dropping the clutch.. and taking off backwards!! Too funny..

 

[LD1]

Wow. Sure glad you didnt decide to give her any throttle in your "diagnosing". That could have been bad

 

[crazyal]

"im a bit amazed. Im trying to think of what type of fuel injection system would let this happen?"

Mechanical.

With EFI the crankshaft position sensor would be going the wrong way so the CPU could shut off the fuel.

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.

 

[k0ua]

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

 

[RaydaKub]

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.