Universal M-18 electric engine kill?

Jimski

.
May 20, 2015
44
Catalina 30 Seabrook
Was just wondering....
My C30 Universal M-18 is stopped by pulling the engine stop cable, which shuts the fuel off at the governor. I'd like to press a button to kill the engine. One way to do this would be to kill power to the facet electric lift pump. I assume I am missing something obvious or it would be done this way.

Has anybody converted the manual pull cable to some electric mechanism?
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
Killing power to the lift pump will not reliably stop the engine. If you really want to eliminate the pull cable look at automotive door or trunk poppers. Pick one with required throw and pull rating.

Les
 
Apr 5, 2009
2,774
Catalina '88 C30 tr/bs Oak Harbor, WA
My M25XP was getting really hard to kill. Got a new cable and now it is a two finger affair.
 

Jimski

.
May 20, 2015
44
Catalina 30 Seabrook
Why - cable is freezing up and very difficult to pull even after lubing it. Labor wise it seems easier to install a kill switch on the fuel pump than replace the cable. But if its not reliable then it cant be done that way. I would not care if it took 10 seconds to kill the engine, I was more convered with what state the fuel system would be in after killing the pump.

I was told never turn the key off while the engine was running because it would fry the alternator diodes. Other than that, it seems like turning the key off would kill then engine when the fuel pressure dropped too low.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
On my boat it might take hours after lift pump is off for the engine to stop. All depends on tank location and how full the tank is.

Do a quick test - with a full tank of diesel start the engine normally then clip the power cable to the lift pump. It will only cost you a barrel connector. I think you will find your motor runs very happily.

Or turn off the key. frying diodes is caused by abruptly open circuit on the B+ terminal (power out) not by collapsing the field (which happens when fully charged anyway). I never do this and advise friends not to but don’t have a good reason.

Les
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
I was told never turn the key off while the engine was running because it would fry the alternator diodes.
Incorrect dock lore and myth..

Get a new stop cable. Killing the fuel pump will only lead to harder start ups. You could install a shut off solenoid but it would need to be done as a one off, with custom bracket, matching the trow, wiring etc. and would cost a lot more than just replacing the stop cable...
 
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Jimski

.
May 20, 2015
44
Catalina 30 Seabrook
Thanks everyone. I think the path is settled. New cable it is...
It would not be a bad thing to replace the shift an throttle cables as well. They are all binding.
 

mortyd

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Dec 11, 2004
952
Catalina 30 easy living
Thanks everyone. I think the path is settled. New cable it is...
It would not be a bad thing to replace the shift an throttle cables as well. They are all binding.
before you spend money wipe down the cable and use some WD40 on it. little lost and it always pays to have some WD40 around.
 
Apr 8, 2010
1,942
Ericson Yachts Olson 34 28400 Portland OR
My former M25XP would run without energizing the electric lift pump, but might abruptly stop, also. Then if warm it would start without that pump, or it might not. Been a while, but I recall that if the engine is turned off while running, the tach also stops indicating, no other harm.