Engine Panel Temp Light Hunter 380

[Toolittletime]

I Don't think my temp light is working. I don't think the temp should light up when the key is turned (the battery and oil light do come on, and buzzer) but it should illuminate when the test switch is pushed up........does that sound correct?
Should I troubleshoot it by grounding out the wire at the temp sensor on the engine to make the light come on?.....looking at the diagram, that should make the light come on........correct?
Or perhaps I just need a new bulb.........looks like the 3/8" one......if someone could verify that for me.
Any other troubleshooting ideas?..............other than cleaning off the corrosion......
Thanks..............Tim

 

[Ralph Johnstone]

Or perhaps I just need a new bulb

Do a quick Ω on the bulb at #1 for an answer. If the bulb is LED, put power across the bulb terminals.

Should I troubleshoot it by grounding out the wire at the temp sensor on the engine to make the light come on?

This "might" be a little trickier and is the reason why I said to check out #1 first if possible. If a ground at #2 lights your light, you're in luck. Repair the fault ....... switch, corrosion, or whatever and it's +/- time for the rest of the day.

If the light still doesn't come on after grounding the switch at #2, you "could" be looking at a fault with the infamous Hunter connection cable. Most often it causes an ignition failure but either one or two connection failures at point #3 on the HI temp. wire could also be an open fault causing failure of the lamp to light when #2 is shorted.

Conside a failure at point #3 ONLY as a last resort. Pray the fault is at #1 or #2. Replacing the HI temp. wire (if needed) is not my idea of a fun afternoon or even a fun week with lot's of brand new nautical language.

Any other troubleshooting ideas?..............other than cleaning off the corrosion......

Good idea. The connectors should be pulled apart, cleaned, covered with non-petroleum grease and put back together.

 

[JoeWhite]

Yes, ground at the temp detector. If the buzzer sounds but the light does not light up, remove the bulb and measure the voltage in the bulb socket by Inserting two short wires. If voltage is present ,then you have a burned out bulb. Swap one from an other display to confirm.

 

[Toolittletime]

Is this a 3/8 inch bulb shown in the Hunter store?

1

827376

RED WARNING LIGHT, 3/8 IN DIAMETER LENS (Hunter )

 

[Toolittletime]

After shorting the temp sending unit to the engine with a short wire, I had power to the light bulb.
Replaced it with one of these.

The 10mm fit perfectly after rounding the hole out very gently with a file.......now when I flip the momentary test switch up, the light comes and buzzer are activated.

Also thinking of adding a temp gauge......something like this. Put it in the heater hose and mounting the gauge up top.

 

[Ralph Johnstone]

After shorting the temp sending unit to the engine with a short wire, I had power to the light bulb.
Replaced it with one of these.

Every once in a blue moon one gets lucky. Congratulations. Maybe buy a lottery ticket seing as how you're on a winning streak.

Also thinking of adding a temp gauge......something like this. Put it in the heater hose and mounting the gauge up top.

Did the same to mine, years ago. Nothing could be easier.

Don't forget the ground wire as the hose is a non conductor.

 

[Toolittletime]

Thanks......I have attached a picture of my engine front.
I think this is a good location, where I marked. I think its the heater hose going to the hwh.....not the return.
That look right??

 

[Toolittletime]

I know it's a 1" hose ......and probably with 5/8 interior dimension. I'll check before ordering.

 

[Ralph Johnstone]

HWH supply is the same hose I used.

Out of curiosity, how much is the hose attachment shown in you post #5. Was not aware of this 20 years ago (likely didn't exist). Mine was all brass fittings (AF environment) and then soldered a ground wire to the "T" fitting. I remember it as less than $10.00 way back when. Today is anyone's guess.

 

[Toolittletime]

22 bucks. All Aluminum

 

[Ralph Johnstone]

22 bucks. All Aluminum

Well crap !

Twenty years ago they would have been giving them away.

 

[Toolittletime]

Does that look like the right hose to put it on?

 

[Ralph Johnstone]

You definitely want the discharge hose TO the hot water heat exchanger.

Unfortunately, I can't tell but the engine does not appear to be a Yanmar GM series. What is the age of your boat ? Can you see the plate on the front of the engine as shown below :

Once you have that, you should be able to find the Yanmar manual in the archives here on this site and check the hose location.

Barring all that, if your hot water tank is full of stone cold water, run your engine and see which hose stays hotter using an IR gun.

Still nothing to hang your hat on ? See if you can find metallic fittings on the two hoses for better sensing to see who's the hotter hose. Or on the hot water storage tank.

 

[jssailem]

SailboatData lists the Hunter 380 - auxiliary

Make:	Yanmar
Model:	3JH2E

 

[Ralph Johnstone]

@Toolittletime , how's the hose hunting adventure going ? Were you able to dig up a copy of a manual on the Yanmar 3JH2E (as per @jssailem 's suggestion) here on SBO ? Or, are you going for the "hands on" approach" ?
Ouch, ouch, ouch.

 

[Toolittletime]

Going for the hands on approach..