Yanmar 4JH3 Just Keeps Running . . . and Running

[ztsf]

Long story short, I pulled into the dock last weekend and was unable to get the engine to shutdown. I wasn't overly surprised because the entire control panel was dead (tach, oil, water and apparently the kill button). I suspect that the switch on the battery main to the panel was somehow out of whack - because the next day everything was fine again (hate those types of problems). Working on that theory though.

No power to panel, ergo no power to kill button, ergo no power to solenoid to shut off the fuel flow. I ended up cutting the flow from the tank, which took an agonizing 10-15 minutes to finally kill it. I could find no manual kill switch/lever on the engine, nor can I see one in the engine manual diagrams.

Questions:

1) Does anyone know if the 4JH3 (I have the HTE version), has a manual kill lever in case the solenoid fails (or I lose panel power like I did)? If so, where it might be located - I presume near the fuel pump.

2) It may not have one, in which case I'm considering mounting a ball valve in line before the pump, in order to cut flow closer to the engine in case of a similar circumstance. Is that a good idea - or am I headed for trouble doing that?

[Privilege]

My 4JH3 (CE) cut off solenoid is just to the right, just behind the flywheel as you look at the engine from the gear box end. It usually has a small rubber boot over it. Pushing (or pulling) it with your finger usually does the trick. There was a post recently which discussed problems with the Yanmar control panels. Once the wiring gets a bit old, it's just not sufficiently sized to transfer the current required to operate the cut-off solenoid or the starter. If your problem doesn't turn out to be an easy fix, I recommend that you have a read of the following thread which discussed the panel problems. (My issues were fixed with a couple of cheap relays).

Yanmar occasionally won't start, then does. - Cruisers & Sailing Forums

[jimbunyard]

There is usually a stop lever mounted on the fuel injection pump to manually shut down the engine. A manual pull-cable 'emergency shutdown' attached to this lever would be a better solution than a valve, in my opinion.

On page 31 in this manual is shown the location of the manual stop lever.

https://www.google.com/url?sa=t&rct=...eWmga1YtROCYnd

That is not an absolute guaranty that your engine is the same of course...

[sailorboy1]

if you just go to the stop solenoid you can push in the rod for the valve just like the solenoid would

[Telemark43]

Originally Posted by ztsf

Long story short, I pulled into the dock last weekend and was unable to get the engine to shutdown. I wasn't overly surprised because the entire control panel was dead (tach, oil, water and apparently the kill button). I suspect that the switch on the battery main to the panel was somehow out of whack - because the next day everything was fine again (hate those types of problems). Working on that theory though.

No power to panel, ergo no power to kill button, ergo no power to solenoid to shut off the fuel flow. I ended up cutting the flow from the tank, which took an agonizing 10-15 minutes to finally kill it. I could find no manual kill switch/lever on the engine, nor can I see one in the engine manual diagrams.

Questions:

1) Does anyone know if the 4JH3 (I have the HTE version), has a manual kill lever in case the solenoid fails (or I lose panel power like I did)? If so, where it might be located - I presume near the fuel pump.

2) It may not have one, in which case I'm considering mounting a ball valve in line before the pump, in order to cut flow closer to the engine in case of a similar circumstance. Is that a good idea - or am I headed for trouble doing that?

On mine, there is a switch externally that shuts off power connect to the panel and alternator for service. When the switch is energized there is no power supplied to the control panel, and no shut off. All the illumination on the control panel is off... the other cause is if the key is turned off... no power to panel. Simple fix if you watch lights on control panel, hopefully !!

[rognvald]

Hi, Z,
A ball valve is not a good idea and may void your insurance. The last time I had a survey in early 2004, I was told to remove the ball valve between the tank and the fuel filter by the surveyor since it was a fire hazard and did not conform to insurance codes(Boat US). As others have suggested, check your wiring. The problem most likely is there. I hope this helps. Good luck and safe sailing.

[navysurfer]

I have the same Yanmar , love it, I put A string via small pulley to shut off plunger then exposed near hatchway, I an stop it if needed, I have seen a runaway Diesel engine and it was not pretty.

Capt Fatty has a funny article about the same thing only stuck in gear in anchorage,

Cheers Pop's

[Smokeys Kitchen]

We have a Yanmar 4JH2, but it had the same solenoid kill switch. Once the system started not working very well, I used a small wooden dowel to push the plunger manually for a while.

We eventually had a totally manual cable stop put in by the local Yanmar repair shop and have had no issues since then. The only way to go in my opinion - no more electrics to worry about.

[Library70]

I have a pair of 4jh3e's. The manual shut fuel shut of is a plunger on tbe flywheel side of the fuel pump. It has a red rubber boot

[jamhass]

I don't have a Yanmar, but I do have a manual fuel shutoff valve mounted before the prefilters. The valve has a lanyard attached that is lead to a lazarette near the helm. This gives an independent way to cut fuel flow, and I consider it a significant safety asset.

It is important to have the lanyard reasonably available, but secure against inadvertent operation (such as when pulling something out of the lazarette.) Don't ask how I know this ...

[jls095]

Just cover the air intake with a hard cover book or piece of wood in a pinch. No need to shut off the fuel supply. It'll die immediately.

[ztsf]

Thank you all very much for the input. Very helpful.

[Cadence]

Originally Posted by ztsf

Long story short, I pulled into the dock last weekend and was unable to get the engine to shutdown. I wasn't overly surprised because the entire control panel was dead (tach, oil, water and apparently the kill button). I suspect that the switch on the battery main to the panel was somehow out of whack - because the next day everything was fine again (hate those types of problems). Working on that theory though.

No power to panel, ergo no power to kill button, ergo no power to solenoid to shut off the fuel flow. I ended up cutting the flow from the tank, which took an agonizing 10-15 minutes to finally kill it. I could find no manual kill switch/lever on the engine, nor can I see one in the engine manual diagrams.

Questions:

1) Does anyone know if the 4JH3 (I have the HTE version), has a manual kill lever in case the solenoid fails (or I lose panel power like I did)? If so, where it might be located - I presume near the fuel pump.

2) It may not have one, in which case I'm considering mounting a ball valve in line before the pump, in order to cut flow closer to the engine in case of a similar circumstance. Is that a good idea - or am I headed for trouble doing that?

In an emergency, take your rain slicker and place it over you engine's air intake.

[savoir]

It's a good idea to attach something to the stop lever to make it easier to grab. Maybe a key rig or a loop of string. There is a hole for that purpose.

[captlloyd]

Originally Posted by jls095

Just cover the air intake with a hard cover book or piece of wood in a pinch. No need to shut off the fuel supply. It'll die immediately.

Keep this idea in mind for a run-away diesel ! A run-away can keep running even after the fuel supply is shut off. It can start sucking the oil out of the pan and use the oil for fuel. You can see a bunch of run-aways on YouTube. Scary.