Actually, nearly all Detroit 2-stroke Diesels use an air cutoff flap for emergency shutdown. Some of them even use this as the normal shutdown mechanism! I'm not aware of too many others that use this scheme, most others use some form of locking the exhaust valve(s) open as the emergency stop, and a stop position or solenoid on the fuel pump.
And, of course, there's the well-known GM passenger car Diesel with NO emergency shutoff, and recommended procedure of washing the air filter in kerosene. If you put the filter back before it has dried, engine go BOOM!
I have taken the access cover off the area that was hiding the speed control, (didn't know that it was a access cover!), anyhow, It seems to be a simple looking lever that doesn't move that much. Perhaps a
1/4" of so. I'm sure a solenoid could be used to control the engine speed and do a SHUTDOWN! when needed.
There doesn't appear to be a return spring of any sorts.
I've uploaded a few pictures of the speed control mechanism to
For a solenoid to work, there has to be current in the solenoid at some point. What would be the source of such current? Does your engine have a DC alternator? Or, are you planning on using generated AC current to control the solenoid? Both DC and AC solenoids can be bought.
Solenoids usually have only two positions. Your manual control seems to have three positions (OFF, START and RUN). That could be another problem for the use of solenoid.
The above questions aside, let's say that you had a solenoid there that could push or pull the lever when necessary. Would its operation be impeded by the manual control? In other words, if the manual control is rigidly connected to the lever (I could not see well), would such rigid connection not make solenoid's work impossible?
Are you planning on removing manual control altogether, or are you planning on using manual control for regular operation and to fit the solenoid for emergency shutdown in addition?
One more question, what is the force that is necessary to engage or disengage the speed lever? (in pounds).
Solenoids are rated for particular forces and your mention that the lever moves about 1/4" is suggestive that it takes substantial force to move it. That may require a large solenoid.
Perhaps, all depends on what size pull/push (in/oz, ft/lb) is required to move the lever. I could alway reverse the lever on the Governor arm, so as to have the lever on the outside and place the solenoid on the outside of the access panel. Just some random thoughts.
I am planning on hooking up a 12V battery so I can use the starter to turn the engine over. Once power is on, I will probably hook up a battery charger to charge the battery between uses.
control seems to
When I was messing with the control arm, with the access panel off, I noticed that there was much difference between START and RUN. The lever didn't seem to move any, but will have to test this when the engine is started next.
If possible, I would hook up a "low oil pressure' bypass switch, so I can start the engine with the solenoid engaged. and once oil pressure has built up to prevent the solenoid from shutting down, release the bypass switch and have the peace of mind.
control altogether, or are you
I would like to do away with the manual control altogether, no need for a redundant speed control, is there?
Thanks for your input, very helpful in my quest for this feature I'm wanting to implement.
I will need to determine the pull/push of this lever. It didn't take much finger effort to move this, but then again, the engine was not running at the time, I don't know if this would make much difference, but will determine this when the engine is running next.
I will have to come up with some kind of gauge to determine the push/pull, any ideas?? I'm sure there is some kind of device, (spring?), that is calibrated for this, perhaps a tool to determine trigger pull on a firearm?
for a pull "down", a regular known weight will work. (such as a food item). For a pull up, the same plus a small block with a tiny pulley if you have one.
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