I am wondering if anyone has developed a system to electrically shut off a 24/2 engine made by poweranand.
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??
seems like it was Jens who fitted a syncrostart solenoid to his 20/2?
he should be along soon
bob g
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
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?
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
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
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.
"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.
Quote from: BruceM on December 31, 2009, 01:14:16 PM
"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...)
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.
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
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
Has anyone ever used a standard engage to stop solenoid valve on the air intake to shut down?
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.
Quote from: BruceM on December 31, 2009, 10:35:37 PM
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.
My engine was custom designed and has a very powerful starter on it. (delco Remy 42MT) I can easily start it without decompression.
I would like to avoid rack closing due to the extra fabrication. Instead I hope to use two solenoid valves (one per cylinder) as well as an electric solenoid for decompression at shut down. I have a 24/2 by Poweranand. Does this sound like a plan?
You say that air intake shut down is a "rude" one. Is decompression any better, though since neither one shuts off the fuel?
Lifting the fuel lever, cuts the fuel off, but would not help if engine is sucking crankcase oil.
But can a cable be attached to the fuel lever, and used for emg stop ? Any reason not to attach a remote cable to it?
Jsw- Be forewarned that some fuel solenoids will not work- the suction of the IP is too great. (I tried and failed with this approach). Further, there is some question as to whether this is bad for the IP, as it will cause cavitation.
The fabrication for a rack closer isn't much - mine is a single piece of bent iron strap I suggest not messing with the fuel, and doing it right (rack closer).
Sure, either secondary method such as decompression or air cutoff would be fine for emergency shut down, as backup to rack closing, since your starter doesn't need decompression.
Quote from: BruceM on January 02, 2010, 04:51:06 PM
Jsw- Be forewarned that some fuel solenoids will not work- the suction of the IP is too great. (I tried and failed with this approach). Further, there is some question as to whether this is bad for the IP, as it will cause cavitation.
Could you explain to me what you mean by "IP"
Also will it cause damage to the engine in any way to just use a air intake shut down as a regular way of shutting down.
IP = injection pump
SR
In my opinion, cutting the air off will cause no permanent damage to the engine, it's a traditional and time honored method of stopping
a runaway diesel right now!
Ron
Air cutoff as the sole normal shutdown on a lister/oid would cause your two injection pumps to keep doing fuel injection until the flywheels stop, which can be a full minute and a fair amount of fuel. That's fine for an emergency shut down, but I don't like it for normal operation shut down.
Bruce:
just asking because i don't know
do you really think it would take more than 10 seconds or so to come to a stop with the intake cut off?
seems like with the engine now being converted into a huge vacuum pump it should suck up a lot of power
and drag the engine down much faster than simply cutting off the fuel and coasting down to a stop?
your point about the injector continueing to pump fuel is a valid one, however.
bob g
Howdy Bob
I've actuated mine several times (experimental only) and it does take (what seems to be) quite a while to come to a stop something in the area of 10 seconds more or less - I'd guess heavy flywheels have something to do with it. before I got the intake properly sealed , it would slow way way down but not quite stop running - eventually had to shut it down by lever.
As for the solenoid operating the IP for shutdown - i've got over 1200 hours running time with a murphy solenoid - no problems with the pump - so far anyway.
(http://t2.gstatic.com/images?q=tbn:7loeepr6ovfJLM:http://www.fwmurphy.co.uk/images/RP23xx_solenoid_medres.jpg) MURPHY SOLENOID
For emergency shutdown the system works fine with only one solenoid operating only one IP. No solenoid for decompression - I figure I want the bloody thing shut down when something goes south. After a coupla overheat(s) (my fault) the engine shut down flawlessly. How often do you need emergency shutdown due to overheat etc - not very often i would hope - so how many redundant systems are really needed (IP shutdown, decompression shutdown, air shutdown etc)
My air shutdown is intended for runaway or other bad things where I might want to shutdown the engine from a distance (outside the space).
After running the engine I like being on site for shutdown - look for leaks (oil fuel exhaust etc) and other possible problems - turn the key switch to the solenoid and let the engine wind down then set the decompression levers.
FWIW - Speaking of air shutdown - lifevests (lifejackets) will keep you afloat but also come in handy smothering a screamin' jimmy. ;D
Cheers, Fred
Okay. Point taken Bruce & Mobile_Bob, I should have said emergency shutdown, the raw diesel being injected wouldn't do the cylinders a lot of good on a continuous basis.
Ron
Bob, I was thinking a minute of coasting and injector squirting as that's what my 6/1 takes to coast to a stop with decompression. It would certainly be much less with compression and pulling vacuum on the intake. Thanks for the correction!
The Murphy rack closer solenoid is an ideal solution for normal ops shut down; Fred has a first class setup.