Fuel Shut Off For 24/2

[Jsw]

 I am wondering if anyone has developed a system to electrically shut off a 24/2 engine made by poweranand.

[dubbleUJay]

IIRC, it was discussed somewhere on this forum, actually for a single, but the twin was mentioned. I cant remember if it was actually done and I also cannot find the thread right now.

Jens, can you recall??

[mobile_bob]

seems like it was Jens who fitted a syncrostart solenoid to his 20/2?

he should be along soon

bob g

[Capt Fred]

why do you want to shut down the fuel - is it due to overheat, oil pressure, fire, runaway engine or ?  Reason I'm asking is there are other, faster ways to shut down the engine in the event of an emergency than cutting off the fuel.

Murphy switchgauge gear works well to shutdown the injector pump - I've also fitted a modified 1 1/2 inch quarter turn ball valve for emergency air shutdown that can be actuated outside the generator room,  works well.


Here's some pictures in another thread in the forum , hope it helps

http://www.microcogen.info/index.php?topic=240.msg3017#msg3017

Cheers, Fred

[Jsw]

My reason to have automatic shut down is to protect from temp, oil, and voltage faults. I plan to use a controller located at the following link:

http://www.datakom.com.tr/products.php?product_id=103

I just need a way to shut it off electrically.

It looks like Capt Fred has a air intake shut off on his. Is it possible to connect this shut off to an actuator and use it as a standard shut off?

[mobile_bob]

yes it is possible, and the only positive way to kill a diesel in my opinion, cut off its air and it will stop running ... period

bob g

[Crumpite]

Folks,

I'm approaching the engine cutoff a different way.

I worry about getting the rings coked up and having the engine run away on the lubricant oil.

That's why I'm looking at an automatic exhaust decompresser driven by a solenoid.

No compression and they won't run either !

I guess the old SOM's used a lever that both pushed the fuel rack close and help the decompresser open.
An excellent system, IMHO...
Daryl

[Jsw]

Is it possible to damage the engine by just shutting off the air intake?




What I would like is if someone has one already made ready to buy. My engine is a 24/2 made by poweranand.

[BruceM]

"What I would like is if someone has one already made ready to buy. My engine is a 24/2 made by poweranand."

Alas, you won't find a kit like this.  And with Listeroid imports direct to the US cut off, I don't think you ever will.  It's going to be a DIY project. 


I use the SOM method-  rack closer and decompression.  (In my case both by pneumatic actuators.)

A Picaxe 08M (or 14 or 18) and RC servo can do the decompression- swinging the manual lever via spring loaded quick link (standard RC "servo saver" hardware, from Towerhobbies.com).  If someone wants to do this, I can do the tiny program for you, and can program your parts, even.   

Rack closer can also be a giant scale servo (TS-80), just.  The same Picaxe chip or a second can do it.  Control for both would be a single pair, low going signal (open collector) says "close rack and decompress".  The purpose of the $3 picaxe chip is just to send the pulses for servo control to either open or closed position.     

[Crumpite]

"What I would like is if someone has one already made ready to buy. My engine is a 24/2 made by poweranand."

Alas, you won't find a kit like this.  And with Listeroid imports direct to the US cut off, I don't think you ever will.  It's going to be a DIY project. 


I use the SOM method-  rack closer and decompression.  (In my case both by pneumatic actuators.)

A Picaxe 08M (or 14 or 18) and RC servo can do the decompression- swinging the manual lever via spring loaded quick link (standard RC "servo saver" hardware, from Towerhobbies.com).  If someone wants to do this, I can do the tiny program for you, and can program your parts, even.   

Rack closer can also be a giant scale servo (TS-80), just.  The same Picaxe chip or a second can do it.  Control for both would be a single pair, low going signal (open collector) says "close rack and decompress".  The purpose of the $3 picaxe chip is just to send the pulses for servo control to either open or closed position.     

Huh, I wouldn't have guess that a servo would be powerful enough !
I can't picture how your system works

A few details would be nice when you get the time, I've been trying to find a solenoid that would work in my application with no luck.
This would solve quite a few problems in my design, yippee !!!

Wait, hold on I just figured it out !
Oh, this is going to be *very* simple.

And the quicker the better as we lost power again for four hours this afternoon...

Thank you !
It's amazing how just a little mental nudge is sometimes enough to steer you onto the right path.
Daryl
(back to scribbling plans...)

[BruceM]

Daryl, let me know if you need some help. I'm an old RC airplane pilot, know most of the linkage tricks.  
http://www.greatplanes.com/accys/gpmq3710.html

That's the old school servo saver (about 3/4 down the page).  It would allow the decompression lever to bump into the valve tappet, until it moves up out of the way.  There are new "servo saver" devices for RC cars and trucks which might be better, but I haven't used them.  I'd put a brass strap around the valve lifter arm, hook a quick link to that, to a servo.

Alternately, if you study the SOM valve lifter, you could implement something like it-  A "tongue" that sticks out, spring loaded, to wedge under the exhaust valve lifter.  This might be easier. The trick to an SOM type lifter is that if you're doing auto starts, you must have the lifter "on" for the entire shutdown.  That way it's assured to be in place, and you'll not stall against compression when you go to start.  With the RC servo, the decompressor only need be actuated for a second to insure it's extended while the engine is turning,  then servo can be powered down, if desired. Gear train friction will hold the servo in place with no power applied, since there is no opposing force.

On my pneumatic ex. valve lifter, I use the far side cam oil plug to bolt down my lifter assembly.  I got a longer one, drilled it out for a hollow brass "reed in the wind" oiler tube, and put a threaded screw in the top to seal it.  t.

Both servos can , but especially the Towerhobbies TS-80 giant scale servo for rack closer needs to run at 6V.  The TS-80 must be set up so that the servo arm is getting within 10 degrees  to pointing at the rack for the closed position.  This gives maximum force for the last little bit of movement, which is needed.  A linkage which pushes a rod (bolt shank) in 1/4" steel pipe to make a "conventional" rack closer comes to mind, but I'm sure you can think of something.  

The rack closer can use the IP mounting bolts to secure a bracket on top of the IP flange mounts.  
I use a simple angle bracket of mine, again, pictures availble.

I suggest RC servos instead of solenoids as they are cheap and powerful, and require little power.

[mobile_bob]

Bruce:

don't know if i ever told you or not, but i am quite impressed with your use of pneumatic cylinders as accuators

nice and cleanly done.

i have been collecting 12volt air valves for years, and have several, along with a couple of the GM 12volt suspension
air compressors, been thinking about integrating them as i get further down the road on my project.

lots of advantages for the use of air, in my opinion, and it looks like you ascribe to the same school of thought.

nicely done

bob g

[TimSR2]

 I support the dual shutoff method. Either fuel shutoff and decompression, or fuel and air shutoff, like the normal Detroit Diesel arrangement.

Reason: Personal experience. I have had an air cooled diesel genset lose it's cooling fan (vibration failure) , overheat to the point of boiling it's lubricating oil, then get shut off by the fuel solenoid slaved to  the oil pressure activated Murphy switch. Problem was-----the superheated lube oil shot past the rings and the set kept running, though at a somewhat lower speed, and surging. If I had not been nearby at the time  the heat buildup and resulting crankcase pressure would have increased to the point that it would have eventually exploded and caught my house on fire.

Anyone want to buy a Wisconsin/Ducati IS11?  It has a brand new, improved cooling fan installed in it. Runs great too.

TimSR2

[Jsw]

Has anyone ever used a standard engage to stop solenoid valve on the air intake to shut down?

[BruceM]

Jsw:
In your earlier post you mention your plan to use of the engine control/monitor hardware. I did download the manual and browse it- it looks like a decent unit.

Given its capability for remote start, like the venerable SOM,  you'll need both decompression and rack closing for normal start up and shut down, and that will certainly suffice for emergency shut down as well.  Air shut off doesn't get you anything but emergency shut down, and rudely at that (fuel still being injected for a minute as the flywheels slow down).

I like the air cylinder actuators for my application, they are cheap, reliable, and powerful, but I realize most guys don't have air.