Yanmar (4 pot) kill switch... how to?

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Folks,
Have the lend of a friend's RIB while I get myself sorted with a replacement cruiser.

I notice there's no kill switch, but was once upon a time.

I queried my friend on this and he said his auto elec said that you need power to introduce the solenoid to kill the engine and that a timer relay was needed because if a kill switch was introduced and used (ie. apply power to the solenoid) that you would burn out the solenoid leaving 12v connected to it for a long time.


Can anyone enlighten me? Or tell me what the traditional method of kill switch is used in the Yanmar engines?

-Edit- Just to add, it is infact a +12v connection to kill the engine using the 'Stop' button on the instrument panel. When you press the button it applies 12v to the solenoid which pulls the fuel cut off
 
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It has a solenoid valve which is energised to cut the fuel. It has to remain energised for long enough for the engine to completely stop otherwise when the button, key or whatever is released the engine will continue to run.

There is no reason why the solenoid should burn out in this time if it is correctly rated.

The system on some engines and cars works in the opposite way. 12 volts is applied to the fuel solenoid to open it.

The fuel solenoid in my (diesel) car is energised all the while the engine is running ... for hours at a time perhaps! If it burnt out I would come to a very unexpected stop!

You dont say what engine but some Yanmar workshop manuals can be found at http://www.motoren.ath.cx/
 
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That's a good point... some solenoid's are +12v to run the engine and don't burn out, so why would this solenoid burn out if 12v is applied for a few minutes?!

I didn't write what model it is, but it's the modern turbo 4 cylinder that does be in many sports cruisers etc. - A quick Google says she's the 4LHA series - I just can't remember which 3 letters followed this
 
That's a good point... some solenoid's are +12v to run the engine and don't burn out, so why would this solenoid burn out if 12v is applied for a few minutes?!

I didn't write what model it is, but it's the modern turbo 4 cylinder that does be in many sports cruisers etc. - A quick Google says she's the 4LHA series - I just can't remember which 3 letters followed this

I was hoping to find a wiring diagram but cannot for that engine.

On a 4JH seres there is just a push button to energise the solenoid so its only energised while you have the button pushed but I noticed a latching relay in the wiring for a dual station set up.

Maybe there is a latching relay on the 4LH series but it only needs to remain on for as long as it takes for the engine to stop turning.
 
I was hoping to find a wiring diagram but cannot for that engine.

On a 4JH seres there is just a push button to energise the solenoid so its only energised while you have the button pushed but I noticed a latching relay in the wiring for a dual station set up.

Maybe there is a latching relay on the 4LH series but it only needs to remain on for as long as it takes for the engine to stop turning.

I will get the exact engine model number tomorrow and then upload the wiring diagram for the engine - they are online but I won't point to it until I know the full model number... i'll be calling on you again tomorrow evening ;)

Thanks for the help
 
Is this RIB an ex MOD Pacific?? If so they likely have non standard SOLAS engine shut down.

However from you description sounds like you have standard Yanmar VDO New B type panel with starter switch and large stop button and motor is 4LHA.

Yanmar use the same Trombetta pattern shut down solenoid on ALL their engine models fitted with in-line injecton pumps, part # is 129470-67320, however you do not want to purchase many at over $500 a pop!

Pricipal is the same as all Trombetta shut downs regardless of engine make, has two solenoids inside the casing, as soon as you key on HOLD IN coil is energised which is a continious rated solenoid, when you hit the starter key the PULL IN coil is temporarily energised, this has an intermittent rated solenoid. Pull in coil is energised though starter curcuit, once you release the starter key the pull in coil ceases to be energised and fuel pump stop lever is held in run position by the the hold in coil using power from the switched battery side. When you hit the stop button the curcuit in the switched battery side is temporarily broken, the return spring inside the mechanical engine shut down snatches the lever back into the sutdown position. Motor will not start until pull in coil is re-energised.

Sounds like another electrician blowing smoke.........RTFM!
 
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Assuming the kill switch is only used for it's intended purpose of stopping you getting chopped up or stranded, rather than stopping the engine without using the normal method, a solenoid would be a small price to pay anyway.... :-)
 
Assuming the kill switch is only used for it's intended purpose of stopping you getting chopped up or stranded, rather than stopping the engine without using the normal method, a solenoid would be a small price to pay anyway.... :-)

As I went to some length to explain, suspect OP already has stop solenoid, a simple kill switch and lanyard can be spliced directly into the shudown curcuit should be simple, just people making life complicated.
 
As I went to some length to explain, suspect OP already has stop solenoid, a simple kill switch and lanyard can be spliced directly into the shudown curcuit should be simple, just people making life complicated.

I also suspected he had a solenoid - I was referring to the fact that if it got burnt out because it was engaged for too long - i.e. on ejection from the boat, it would be a small price to pay. :-)
 
Folks, i'm off soon to take pics of the control panel/solenoid etc.

You guys are correct, there is a stop solenoid on the boat which requires a +12v feed to kill the engine. When 12v is applied to the solenoid (by pressing the Stop button) it pulls a lever which kills the diesel supply presumably.

It would be great to splice into the stop button and work from there, I just wondered if the solenoid could 'burn out' (as someone who wants to charge to fit a timer relay has suggested)

I'm also guessing that i'll need to find a kill switch that MAKES when the kill-cord is pulled, rather than BREAKS when the kill-cord is pulled?
 
I also suspected he had a solenoid - I was referring to the fact that if it got burnt out because it was engaged for too long - i.e. on ejection from the boat, it would be a small price to pay. :-)

Unless engine has SOLAS set up, hold in solenoid which is designed as continious rating keeps motor running, break the curcuit, de-energise the the solenoid with kill swich and motor shuts down due to the action of the shut down return spring.

Is this a difficult concept to grasp?

I have known yard numpties to trgger the pull in solenid when trying to bleed an engine instead of slipping off the ball joint and holding stop lever open. The pull in solenoid has life of Spanish cigarette lighter if subject to anything more than an intermittent load.
 
Folks, i'm off soon to take pics of the control panel/solenoid etc.

You guys are correct, there is a stop solenoid on the boat which requires a +12v feed to kill the engine. When 12v is applied to the solenoid (by pressing the Stop button) it pulls a lever which kills the diesel supply presumably.

It would be great to splice into the stop button and work from there, I just wondered if the solenoid could 'burn out' (as someone who wants to charge to fit a timer relay has suggested)

I'm also guessing that i'll need to find a kill switch that MAKES when the kill-cord is pulled, rather than BREAKS when the kill-cord is pulled?

Your post came in between my last and everybody appears to be talking past each other.

Standard Yanmar in-line injection pump set up with solenoid #129470-67320, is power to RUN NOT power to shut down. Are you absolutely CERTAIN that you have the SOLAS power to shut down set up?? This was my first question.

Quote your engine # to Barrus to confirm exactly what you have.
 
OK folks so here's some more info....

First, find a video of the stop solenoid in action... (click image to play)



STOP button pressed:
IMAG0073.jpg


STOP button released:
IMAG0072.jpg


Control panel:
IMAG0071.jpg



Can anyone offer any advise here on the best way to install a kill switch?!
 
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