Rolled my 3240, and it ran till it blew ??

[SteveCornell]

I found these instructions from one of the manufactures of air kills...

Any engine crankcase breather connections into
the intake system between the MVX valve and
engine, or any internal crankcase breather
arrangement venting directly into the engine
intake ports must be sealed and replaced by an
external breather system venting either to
atmosphere or to the intake system upstream of
the shut down valve. External breather system
kits for various engine types are available from
Chalwyn.

So it looks like the real culprit here is the crankcase vent plumbed into the intake.

 

[TalonDancer]

So here's an off the wall idea....

What if someone made a CO2 'bomb' that could be placed in the air intake (say an air cleaner extension) that would be triggered by a mercury switch in the event of a roll over?

Talon Dancer

 

[RadarTech]

So here's an off the wall idea....

What if someone made a CO2 'bomb' that could be placed in the air intake (say an air cleaner extension) that would be triggered by a mercury switch in the event of a roll over?

Talon Dancer

sounds simple---
Just get a couple of those CO2 cartridges for those air guns..
and build a device....


J

 

[DiezNutz]

Restricting the intake may be a good emergency shut-down... in theory. But just be aware these little, high compression diesels really want to keep running... way more than a gas engine of similar size. They will literally try to ingest anything you stuff in the intake pathway... rags, cardboard, your hand, tools... virtually anything. They will actually collapse the intake plumbing trying to get air.

Good point, and I wouldn't ever stick my hand over the intake with the thing running unrestricted and wide open...

Usually you get run away on an old engine that sucks oil through the rings. What may have happened in your case was the tractor turned over and oil sat on the underside of the pistons. As the piston moved downward on the intake stroke it sucked the oil through the rings and this fueled the engine.

For it to have been getting that much oil past the rings, it would've been having compression problems, and on the verge of running away anyway, right-side-up. From all indications the engine was mechanically sound prior to this... should hope so, it's only a 2007.

Well it appears I'm very lucky in more ways than one......It appears the engine is OK, the only explanation to this is indeed it had to be running on it's own oil and once the oil got low enough that it quit running into the cylinders (or out the vent line)the tractor quit, there was still a couple quarts of oil scattered throughout the engine so I guess this protected it.

Steve, that's great news and I hope the end of your problems! :drink:
I don't want to be Debbie Downer here, so I'm really hoping the intake ran out of oil before the pickup tube did, otherwise you still might have some latent bearing damage somewhere. On my B engine, the pickup tube sits more toward the left, which means it would've been higher than the breather tube. Smart thinking to change the oil & filter right away! Keep an eye out for strange engine noises and oil pressure problems (e.g., when warm). I really hope I'm dead wrong in this case, and it didn't happen that way. It's just amazing you didn't spin a bearing and/or throw a rod from overreving in this condition! Wow.

So it looks like the real culprit here is the crankcase vent plumbed into the intake.

Yes, that's why CrazyAl and I first suggested if you were going to put a shutoff someplace, the first option is the breather tube. Since it's just a hose, it's easier to muck with than your intake system.

Or, plug the intake breather tube port and run the valve cover port to a catch can (if you're environmentally friendly). Which, if you're going to switch over to an external breather anyway, then you don't really need the intake shutoff to prevent this problem.

Best of luck!

 

[Big Wave D]

My L-35 has a fuel shut off valve at the fuel filter, so I can keep all the fuel from running out while changing the filter.

I would have turned the fuel off there.

Does anybody know how long would it run with that turned off?

I can't imagine much more than a minute or so. I've never tried it so I don't know.

 

[SteveCornell]

It wasn't running on fuel, the fuel solenoid was closed, it was running on oil coming into the intake hose via the crankcase filter, shutting off the fuel valve would have made no difference.

The key was off, all of the fuses were removed and it just kept running on the oil, it was smoking like a house on fire and finally quit once the oil quit running into the intake via the crankcase breather hose.

The tractor is an HST so there was no way to stall the engine (no oil to the pumps when it's on it's side), I engaged the PTO (mower was on) and the drive shaft was in a bind, this slowed it down and I thought it was going to kill it until the u-joint ripped out of the PTO drive shaft.

I tried everything, even tried to get to the air intake but I could not get the hood open, all I could do was watch it smoke and hear it scream until it finally died.

I now have a pretty good understanding of what happened now but I still don't understand why it didn't die when I left the seat, I guess I didn't have my foot on the HST pedal and the PTO was not engaged so the safety features that kill the fuel were not activated and by the time I got to the ignition switch he tractor was already on it's side and oil was running into the intake and there was no shutting it down.

 

[Big Wave D]

Ah, I see.

Well, thanks for setting me straight.

Is there any way to splice a check/ball valve into the crankcase vent tube to at least prohibit enough oil from making its way into the air intake to support continue running?

 

[TalonDancer]

..... I still don't understand why it didn't die when I left the seat, I guess I didn't have my foot on the HST pedal and the PTO was not engaged .....

That's a really good point.... the seat safety switch mechanism doesn't really help in the case of a roll over because you would have to keep your foot on the HST pedal as you got out of the seat. Not something most folks would do. What's needed is a mercury switch to cut off the fuel at say anything over 45 degrees.

Talon Dancer

 

[radioman]

I now have a pretty good understanding of what happened now but I still don't understand why it didn't die when I left the seat, I guess I didn't have my foot on the HST pedal and the PTO was not engaged so the safety features that kill the fuel were not activated and by the time I got to the ignition switch he tractor was already on it's side and oil was running into the intake and there was no shutting it down.

First of all, take a step back and think about the safety switches. What do they really do ? IF any of those switches is activated, it sends a current to where? The fuel soleniod! All it does is activates the plunger to fuel plunger to cut off the fuel to the engine. If the engine finds another source of fuel- all the saftey switches in the world will not shut off the engine.

I agree we need another safety switch. We will need one for a runaway engine kill. Perhaps if we have a switch that senses a rolloverr, lets say 90 and greater degrees off axis, it would kill the air source.

At this point of time, I would say you will need to consult your owners manual to see how to check your saftey switches on your tractor to make sure they all work. the pto, hst, seat ,etc safety switches should all be working.

 

[Brad_Blazer]

Steve you are a lucky guy.

This is a great cautionary tale despite your apparent lack of damage. I would say that in your case the tractor angle probably had oil coming through the breather immediately and there was no lag time where a fuel shutoff procedure would have worked. It also takes a several seconds for an engine to come to a complete stop where the reintroduction of fuel will not cause a restart.

The only suggestion I might add is to try to redirect the exhaust to the intake with a tarp, hose, or whatever is handy, even if it's just blowing in the right direction. It's a big supply of CO2 sans O2.

Brad

Edit: I just realized you have 2 threads going (Owning/operating in addition to this one) I thought my post from yesterday disappeared.