Yanmar 2Gm20 starting issues

[Brinky63]

Hi All,

My hunter306 has a Yanmar 2Gm20F and has given me starting issues for the past weeks but now just refuses to start.

We checked voltage at battery and starter which is all good. We checked voltage at the starter when turning the starter switch/button over but get nothing. I replaced the Lewmar engine control (non magnetic single lever) with the same results.

The first Engine start after installing the new Engine Control was successful, she started right up. Subsequent starts did not work. Played with the lever taking it out of neutral, shifting it, then placing in neutral to start but nothing.

The engine control (both old and new) have a Neutral safety switch built in but there are no cables running to this switch.

Question is where is the Neutral Safety Switch or How does the lewmar engine control and the Yanmar engine control the neutral position?

 

[Dave Groshong]

Do you have a neutral pin covered by a rubber boot?
http://shop.hunterowners.com/hp/part.php?m=33&c=12&p=52552
http://shop.hunterowners.com/hp/part.php?m=27&c=12&p=52999

 

[kloudie1]

Might not be the safety switch.. Might be bad connections in the harness, a well known problem..
read this thread: https://forums.sailboatowners.com/index.php?threads/starter-wiring.128862/#post-807877

 

[Brinky63]

Do you have a neutral pin covered by a rubber boot?
http://shop.hunterowners.com/hp/part.php?m=33&c=12&p=52552
http://shop.hunterowners.com/hp/part.php?m=27&c=12&p=52999

Yes it has the rubber boot. The engine goes into neutral and gear nicely. The engine control unit is brand new.

 

[Brinky63]

Super will look into the wire solution and clean up connections at the same time. Will keep you posted.

 

[Jim 5757]

Sorry I don't mean to be dense here but is it not starting? Or is it not cranking?

 

[Justin_NSA]

Sorry I don't mean to be dense here but is it not starting? Or is it not cranking?

That's the first question I have also.

 

[Bill Roosa]

the problem is classic to Hunters. they use lots of quick connects in the engine and hull to speed building the boat. Over time all those connections develop a little resistance. All fine and dandy except there are like 16 connections. You can test the voltage available at the starter by probing with a volt meter at the starter control wire and ground while a helper attempts to crank the engine. I would recommend neutering the boat engine electrical of all the quick connects as they also effect the engine instruments. Did that a few years ago and have never had the problem reappear. The normal voltage drop across a connection should not exceed 0.2 volts. with 16 connections times 0.2 volts per connection you get a loss of 3.2 volts. Even more if there is corrosion on them!!! when cranking the voltage drops even more so seeing more than 9 volts (minimum needed to engage the solenoid) gets pretty unlikely.

 

[Benny17441]

Before we get side tracked, clear up if the engine is cranking or not. The gear selector is a mechanical unit and not likely having to do with the engine cranking or starting. Bill Rosa offers a good explanation of how voltage drop affects the starter circuit. It is a known malady of older Hunters. You can piggy back and hardwire a push button switch close to the engine compartment somewhere around the companionway. If the engine cranks but does not start is another set of circumstance with a high percentage being fuel related.

 

[Hunter Ad Bot]

And now a word from the sponsor...

Rub rail for Hunter sailboats

After many years of shortage, we now offer rub rails for most Hunters from the late-90s and newer. Insert and keeper/track available.
See the product

 

[Brinky63]

the engine does not crank.

 

[Brinky63]

great input, will look at this. for the record the engine does not crank.

 

[Justin_NSA]

great input, will look at this. for the record the engine does not crank.

Trying to be methodical: You said "We checked voltage at battery and starter which is all good". If that were correct, it should crank. How did you check voltage at the starter? Did you check voltage on the solenoid when you activated the switch?

 

[Brinky63]

correct.

 

[Justin_NSA]

correct.

If by "correct" you mean you checked that proper voltage is getting to the start solenoid when you activate the switch and you still don't get engagement, then your starter is bad. All of the other interlocks i.e. safety features are designed to interrupt power to the solenoid.

 

[Jim 5757]

Two people and a voltmeter. Try cranking the engine. Assuming the engine won't crank, hold the switch(or switches) While the 2nd guy measures voltage from batt + terminal to solenoid. Ideally you should get 0 volts. More than a volt or two you have the wiring issues mentioned above.

 

[py26129]

Do you get a click when you try to engage the starter?

If yes then the issue is probably related to a voltage drop between the starter button & the starter solenoid. This is a well documented issue.

The accepted fix is to insert another solenoid into the circuit. I have used the Radioshack PN: 2062477 when I implemented the fix on my boat.

The solenoid should have four posts, two high amp, two low amp. On the low amp circuit, connect the starter key wire to one post, and ground the second post. Engagingthe key will trip this circuit. On the high amp side, connect a #8 gauge wire from the solenoid to the battery/alternator post on the starter motor. Then from the second high amp post run a #8 gauge wire back to the post on the starter where the wire from the key originally came from.

Engaging the key will trip the low amp circuit which in turn engages the high amp connection which gives you a very healthy current to the starter solenoid.

 

[Brinky63]

So I have a successful update on the starter issue, some lessons learned and still one question pending.
We checked the cables and found that the previous owner already had run a second power/red cable with 30 amp fuse to the starter. The fuse connection was a bit sketchy so we replaced it and cleaned the terminal connector on the solenoid. The white cable running from the start button to the solenoid had issues that needed attention. The terminal connector on the solenoid needed cleaning, there was also a male/female connector before the terminal connector, which had no proper seal on it. This connector was completely filthy and dirty, we replaced it with a splicer with heat shrink to keep it sealed. The nut that kept the terminal connector (white cable) on the solenoid did not tighten correctly, we replaced it with a nut-bult-lock washer to make sure it was nice and tight.

The engine started 10 out of 10 times after the above, super news.

One question I still have is how this engine controls starting when in gear, right now I can start the engine while it's in gear. The lewmar engine control unit has a switch in the handle but was not connected in the one i remove, there are also no cables running together with the gear cables. Anyone have an idea or do I enter a new thread/post?

Thanks all for the help.

 

[Hello Below]

Anyone have an idea or do I enter a new thread/post?

Given it is related and discussed in your original post, I think we can carry on with this thread.
I also had a Lewmar single lever engine control with a neutral safety switch that was not connected. I say "had" because 2 weeks ago I finally got around to connecting up this safety switch. I do not have easy access to the back of the cockpit engine control panel, so I ran 2 wires from the switch to the engine room. There I simply connected the safety switch in series with the starter solenoid/start button control line (white). That is all that is needed. When the engine lever is in neutral the safety switch is closed completing the start circuit. When the lever is in forward or reverse the switch is open breaking the start circuit. This maybe all you need to do.
In my case, the original wire from the solenoid to the start button was 16 AWG. I used 14 AWG from the Lewmar safety switch to the engine room. I figured the total round trip for the start circuit was at least 40 ft. That is a long distance for that gauge wire to carry all but a small amount of current. I could not find the specifications for the Yanmar/Hitachi starter solenoid anywhere on the internet. So I measured the solenoid coil resistance and found that to be less than an ohm (0.5). Keep in mind that at extreme ranges VOMs accuracy can be suspect. I measured the current necessary to energize the solenoid and found that to be >19.99A which is the maximum my meter can measure. This is consistent with ohms law. I also found that the voltage at the solenoid was 8.75V, a huge voltage drop. I ended up putting a Cole Hersee relay in the solenoid control line with a coil resistance of 17.5 ohm. This makes me a whole bunch more comfortable with the control wire sizing I have. The 12V across the contacts of this relay, of course, now feeds the starter solenoid.

 

[Brinky63]

Hello Below, thanks for the input. Access is tough also on my boat. Will try your configuration and keep you posted.