Start button

Rich Stidger · Jun 21, 2026

The actual start button switch is a low current device that just supplies power to the start solenoid on the starter. This start solenoid then supplies the heavy current to the starter.
So if you are just relocating the start push-button, I think all you need to do is to extend the existing wires on the push-button to the new location of choice. Be sure to use a wire size that is at least as large as the original wires on the pushbutton.
If however you are relocating the entire engine panel, then you need to build a harness for all of the wires that connect to the panel keeping the same wire colors as the original. Keeping the same wire colors will enable you and future owners to t/s any future problems.

Ralph Johnstone · Jun 21, 2026

Rich Stidger said:
The actual start button switch is a low current device that just supplies power to the start solenoid on the starter.

Interesting what you say @Rich Stidger . I know that's the case with most boats but not so much with a Hunter. We have that famous "Hunter Solenoid Booster" which many Hunter owners (me too) installed to overcome the many connections along the way from the starter button to the starter solenoid. My starter motor solenoid used to "try" to pull 18A (and quite often failed) before I installed the solenoid booster. This is the "as built."

To be honest, I'm not sure if the Hunter starter motor solenoid asks for a hell of a lot of amps on startup or whether all starter solenoids require this large draw but have no problems because they have better quality wiring. Who knows ?

Before diving into this with the wrong wire, or using a solenoid where one is not required, I suggest you measure the amperage draw in series with your existing starter button.

Installing a solenoid is something extra to fail. You've got to run new wiring anyway so find out what is needed.

Davidasailor26 · Jun 21, 2026

Some boats

Rich Stidger said:
If however you are relocating the entire engine panel, then you need to build a harness for all of the wires that connect to the panel keeping the same wire colors as the original. Keeping the same wire colors will enable you and future owners to t/s any future problems.

This was my thought too, or at least moving the “ignition” key or switch. Moving just the button separates it from the on/off and glow plug controls that you probably want in the same place.

sailcapt340 · Jun 22, 2026

If I could please beg your indulgence, and also ask a question for myself. Your post came and I was just about to add my own regarding almost the same subject. What timing!

On my 2000 340, a few years back I was going to add a Solenoid Booster (as Ralph suggested) because I was having that Yanmar Intermittent Starting problem. I cleaned the inline connections in the harness and it worked fine again…..until just yesterday. It came back.
I cleaned the contacts in the Connector Harness and all was fine, again. And they really didn’t look like they needed cleaning at all.

But I would like to ask, as this wiring connector harness seems to be my issue…..can I just cut the wires, add butt connectors with longer lengths of wire to each one and eliminate the whole connector harness entirely? And avoid running new wires back to the starter button.

Thank you for allowing me to join in here. And thank you for the help as well.

kloudie1 · Jun 22, 2026

Instead of the booster solenoid, I replaced the "hot" wire with a length of 10 gage wire and a new fuse holder. No more multiple connectors; has been working fine for several years now.

garymalmgren · Jun 22, 2026

Something different. $1;50 from China.

garymalmgren · Jun 22, 2026

RE:
But I would like to ask, as this wiring connector harness seems to be my issue…..can I just cut the wires, add butt connectors with longer lengths of wire to each one and eliminate the whole connector harness entirely? And avoid running new wires back to the starter button.

Yes, BUT, why add butt connectors or any connectors that as you have found will fail.
Cut wires, slip over some shrink wrap, solder wires together and shrink the wrap.
$1:50 from China.
The original Yanmar wiring loom was supplied with connectors so that it could be fitted in many different formats.
Once the wiring is installed (permanently) there is no need for those connectors at all.
So, eliminate them!

sailcapt340 · Jun 22, 2026

Gary,
I would like to do as you said. Just cut, solder and shrink wrap. But the challenge I have is, there is NO play in harness wiring at all. I would guess less than 1/2 inch of play is available to disconnect the 2 halves of the harness. It‘s hard to just pull it apart.

Once I cut the wires as close to the harness as possible I am left with about a 3 inch gap between both ends.
That's why I thought of a connector on each of the ends of the wires, with at least 3+ inches of wire between each to ease the tension in the whole wiring run now.
Thank you. It is good to know I can cut the wire harness out and splice them together.

Ralph Johnstone · Jun 22, 2026

sailcapt340 said:
If I could please beg your indulgence, and also ask a question for myself.

With an introduction like that, how could anyone possibly object ? As anyone can see, you are both a scholar and a gentleman unlike the usual rank and file which occupy these pages. BTW, if you could see your way clear to advance me a fiver until next payday, I would be forever in your debt.

sailcapt340 said:
I cleaned the inline connections in the harness and it worked fine again…..until just yesterday. It came back.

Same here but maybe it was the start push button that was frequently adding that one extra little Ω which would not allow enough amperage to engage the solenoid. 12 VDC doesn't have very much push and 18A engaging current is just on the upper limit of looking for failure. After fooling with the inline connection just once, that was more than enough for me and I jury rigged a booster :

.................... behind the engine and, out of site out of mind. I had also looked at eliminating the connector but too many wires and just no space in which to work.

Ralph Johnstone · Jun 22, 2026

@garymalmgren , my admiration of your very nice job of altering my original drawing :

So nice in fact that I have contacted my legal team of "Dewey, Cheatem, and Howe" to have them look into a copyright infringement suit

.
Every penny counts in these difficult times you know ?

But all that aside, I have to say, that is the #1 solution for the OP's starter button migration problem. As long as he remembers to change the batteries as required. An added bonus is that he could start his engine long before he gets to the marina.

sailcapt340 · Jun 22, 2026

Ralph,
I thank you for the compliment. As far as the fiver til payday, that kind of sounds like “Wimpy” and “ I’ll gladly pay you Tuesday for a hamburger today”.
Was it really easier to run a new wire back to the starter button, than eliminate the harness on your boat? I recently rerouted new VHF cables through the wiring harness and up into my pedestal and that was possibly the last I can fit in that area and mass of wires.
I know others have said they also ran a new 10 AWG wire back to the pedestal as well.
I have the open space to work in, not so much the give and take of the wires themselves, at least until I cut them.
I think with some good sealing connections and quality shrink wrap over all, I may be in luck with the removal and cure. I hope so at least.

Ralph Johnstone · Jun 22, 2026

sailcapt340 said:
Was it really easier to run a new wire back to the starter button, than eliminate the harness on your boat?

The reason for going with the super duper "Hunter Booster" is that I didn't have to run any new wires anywhere. It's all the same old dusty 1998 wiring in there. Good Gawd, if I had to install new wiring from the engine back to the starter button, I would have burned the boat to the water line, pocketed the insurance money and walked away. Nothing and I mean NOTHING more could have been run back there without me doing myself a serious injury. Absolutely out of the question :facepalm:

!

Before we dive into this exercise, only one small thing to remember here, there is an old relay hanging off of the Yanmar called the starter motor relay or just starter relay. This relay is what closes the electrical contacts only to engage the starter motor. It does not turn the starter motor as that takes 187A.

The starter relay is a bit of a bugger and requires about 18A to get it to do its job.

The booster relay (the Super Duper Hunter Booster) is a brand new relay (about $30.00 way back when) you will purchase called a Cole Hersey relay (booster relay for short) and only requires 0.69A to do its job.

Keep this clear in your mind and you've won the battle.

Let me take you through the old 1998 era ignition wiring and show how it kicks the little starter relay into action every time without even half trying. A hundred years from now, when the ignition wiring and the connector is really in bad shape, IT WILL STILL ACTIVATE THE BOOSTER EVERY TIME WITHOUT FAILURE.

Here is the original ignition wiring installed ny Hunter :

It worked when new but as the connector and push button developed a tiny bit of corrosion, the current to the starter solenoid dropped to 17A as I saw on my battery monitor and the starter solenoid lay there dead. When the starter solenoid DID work, it was pulling about 18.5A. 17A no go, 18.5A yes. Not always but enough to piss you off.

Here we have the Cole Hersey relay (booster relay) installed :

The old wiring by Hunter is now required to pass only 0.69A because of the small size of the Cole Hersey relay (booster relay) but the contacts in this small relay are capable of handling up to 80A if the need was there. If the need were more than 80A, the little relay would go up in a ball of fire. The crappy old wire will be able to pass 0.69A for many, many years because the old wire and connection was able to pass 18A at one time and has only developed a small amount of corrosion over ..................... how many years ?

The new wire required is only a couple of feet to reach the booster relay and then away to the starter relay. I erred waaaaay on the safe side and moved the newly added wire up to #12 AWG just to take care of the extra resistance in the additional contacts.

kloudie1 · Jun 22, 2026

Small clarification.. After looking at the Yanmar wiring, and doing a little research on wire size etc, I decided to feed the key switch with a bigger wire and a better fuse holder.. attached wiring diagram shows the red wire from starter to key switch; that is the one I replaced. I figured that nothing else in that system needed high current .. The individual grounds seem to be fine since all the buzzer/lamps work when the key goes on.. The wire on the H-34 is easy to access.. I figured if the starter hesitation gave me any more problems, the booster was a great fallback.

Ralph Johnstone · Jun 22, 2026

fred1diver said:
Do you have a link to order one?

#1 guess would be Amazon and

#2 guess would be AliExpress

Ralph Johnstone · Jun 22, 2026

kloudie1 said:
attached wiring diagram shows the red wire from starter to key switch; that is the one I replaced

Definitely the better way to go and avoid an additional relay (the booster relay) if you can get anywhere near the wiring.

I'm retired, hence took the lazy way to do it.

dlochner · Jun 22, 2026

kloudie1 said:
Instead of the booster solenoid, I replaced the "hot" wire with a length of 10 gage wire and a new fuse holder. No more multiple connectors; has been working fine for several years now.

I also rewired the solenoid wires with 10 ga and took the ignition power directly from the DC+ bus instead of the starter's DC+ connection. Works well for many years and simpler than adding a relay.

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