[preservedkillick]

Setup: House bank of two 6 volt golf cart batteries wired in series. Few years old, good shape. Boat has very low amp needs. Starter battery: 7 year old Napa Grp24 dual purpose, used to start a 22 hp Vetus Diesel. Batteries separated by a Blue Sea Charging Relay and Switch. Wiring is 4 years old 1/0. Appears clean and tight.

Symptoms: Starter slow, or intermittently does not engage. This has been going on for the last two seasons. Bit worse this year.

Tests: Start battery at 12.6 or 12.8 volts between posts. When cranking, voltage drops to low 10's, possibly high 9s. Combining house and starter batteries using the Blue Sea switch does not help. Having fully charged batteries does not help.

Where is the problem?

1. Battery? Starter battery at 7 years old certainly is on its last breath. However, I've had it load tested and they tell me it is still fine. And, combing batteries does not help. I believe house batteries to be fine, though I've not checked them recently. Symptoms persists with all batteries fresh off the charger in the spring.

2. Wiring setup? I've got a 150A Blue Sea BusBar for the various ground wires. The ground from the starter connects to this Busbar, with a separate wire to the negative stud on the battery. Could I be loosing voltage though the busbar? Better to connect starter ground directly to battery?

3. Poor Connections? I did this wiring myself, using good quality 1/0 wiring, and an Anchor Lug Crimper and a vice, with heat shrink over the joint. Do I simply have a loose/bad connection?

I'm aware that there are more indicative tests to help find wiring issues specific to which circuit, but in my situation they require longer leads on the multi-meter, and three people, which I don't have at the moment.

I'm thinking there's a connection issue, but I'd love to hear from the experts on this.

Preserved.

 

[eherlihy]

Where were the test points for battery voltage?

I will guess that you checked at the battery. It would be most revealing to test again at the starter solenoid (+ lug, and engine ground).

 

[Don L]

Tests: Start battery at 12.6 or 12.8 volts between posts. When cranking, voltage drops to low 10's, possibly high 9s. Combining house and starter batteries using the Blue Sea switch does not help. Having fully charged batteries does not help.

Where did you measure that low 10s/9s at? If it was at the battery terminal you have a bad battery. If it was at the starter you have a wiring problem most likely a terminal. If it was at the starter solenoid you have a bad start switch, wiring problem, or a connection corroded.

If your start circuit takes power from the battery to the start switch and then to the solenoid any little corrosion in that circuit will cause a start problem.

 

[preservedkillick]

The 10s/9s were measured at the battery posts while cranking. I get 12.6+ under no load, then low 10s while starter in cranking. The thing is, when I take the battery to Napa they load test it and tell me the battery is fine. And, wouldn't combining the batteries (house and start) help if it were the start battery?

 

[Vasco]

Common problem with wiring in older boats. Simplest solution is to install a relay. I finally bit the bullet and did that with my 26 year old boat. And I had new batteries! Get a relay from NAPA. Half hour job and the engine will start every time you push the button.

 

[preservedkillick]

Common problem with wiring in older boats. Simplest solution is to install a relay. I finally bit the bullet and did that with my 26 year old boat. And I had new batteries! Get a relay from NAPA. Half hour job and the engine will start every time you push the button.

Rick,

I'm not sure I understand? Is this to address an engine control panel switch issue? In my boat, the engine control panel is about 12 to 15 years old, but all other wring is new?

 

[TropicCat]

I've had the same thing happen to me on my starboard diesel, where the ground and hot wire run about 12 feet to that engine. Find Your black wire engine ground. Remove it from the engine, and clean it with sandpaper or put on a new lug and then screw it back onto the engine. In my case I installed new wire lugs on both 12v and ground. The problem was solved and it didn't cost anything.

 

[preservedkillick]

Find Your black wire engine ground. Remove it from the engine, and clean it with sandpaper or put on a new lug and then screw it back onto the engine.

Thanks Tropicat. All wiring is shiny new clean. I don't think corrosion is an issue.

 

[Vasco]

Rick,

I'm not sure I understand? Is this to address an engine control panel switch issue? In my boat, the engine control panel is about 12 to 15 years old, but all other wring is new?

It's for the engine control panel wiring. Installing a relay between the panel wiring and the solenoid will boost the voltage and it'll start every time you push the button. Here's the instructions that I borrowed from another site. Cleaning all the contacts from the control panel might help but installing a relay really works well.

The relay part# I use:
Tyco
12V
V23234-A0001-X032

There are 5 pins on the relay:

87 - Jumper to starter male spade terminal
86 - Wire from Yanmar panel (used to go directly to starter)
30 - Positive jumper from large positive cable attached to starter.
85 - To Ground
87a - Not used

So, without this relay, you have 1 large nut on your starter, with a rather thick positive cable on it (this should come from your start battery). And, you should have 1 smaller cable, with a spade female disconnect on it that is connected to a spade post on the starter (this will come from the Yanmar engine panel at your helm station).

You need to remove this wire from the spade on the starter, connect it to position 86 on the relay. Then you make two short runs of cable, one going back to that spade male terminal on the starter from position 87, and another one from the big nut/positive cable on the starter to position 30 on the relay. Then a short ground wire to your engine ground from position 85 on the relay.

 

[Capt Len]

If the starter motor brushes and commutator are not healthy that's what you can get. A little bilge oil and water ?? If starter wherrzz but doesn't engage look to the Bendix spring and or shaft it slids on (ford type)

 

[hellosailor]

If you take a known good battery, and jump it directly to the starter with short fat jumper cables, that will tell you if the problem is internal to the starter, or out in your wiring.

Divide and conquer.

If it still doesn't want to start, you drop the starter and start rebuilding the solenoid and/or starter motor, something you might DIY or drop at a shop.

 

[preservedkillick]

If you take a known good battery, and jump it directly to the starter with short fat jumper cables, that will tell you if the problem is internal to the starter, or out in your wiring.

This sounds like a good idea, thanks!

 

[mitiempo]

It's for the engine control panel wiring. Installing a relay between the panel wiring and the solenoid will boost the voltage and it'll start every time you push the button.

I disagree. The starter solenoid doesn't use much current. That is why there is a solenoid there to start with. If the voltage at the solenoid isn't as high as it should be there is a wiring problem to or from the panel, either gauge, connections corroded, or age of wire. Adding a relay (really another solenoid) will not solve the problem only mask it and add more connections at the same time.

Now if there are glow plugs and they are powered off the panel a relay does make sense as they do use a lot of current.

 

[Vasco]

I disagree. The starter solenoid doesn't use much current. That is why there is a solenoid there to start with. If the voltage at the solenoid isn't as high as it should be there is a wiring problem to or from the panel, either gauge, connections corroded, or age of wire. Adding a relay (really another solenoid) will not solve the problem only mask it and add more connections at the same time.

Now if there are glow plugs and they are powered off the panel a relay does make sense as they do use a lot of current.

I agree the problem is from old wiring. But rather than change out the wiring harness it's much easier to install a relay. The relay does not mask the problem it fixes it without having to get a new harness. As I said in an earlier post you might try cleaning all the contacts first.

As for the relay in some newer Yanmar installations a relay is already installed.

 

[Don L]

a relay only adds a couple of feet of wire

but if the problem is a bad connection from the switch to the solenoid in time the relay even wouldn't get power (still worth having the relay for times when starter battery voltage is at it's lower limit)

 

[MarkSF]

I've spent quite a bit of time trouble-shooting an intermittent no-start problem, that only occured after the engine had been heat-soaked (ie, re-start an hour after shutdown). The solenoid went click, but the starter did not spin up.

There are many things that can go wrong.

1) You need a healthy voltage to activate the solenoid. This is down to the ignition switch and wiring.

2) You need a healthy voltage at the starter main terminals. This depends on the cabling, battery switch, and starter battery.

3) You need a healthy starter motor.

Firstly, you need to systematically measure the voltage drops in your system. The starter motor needs at least 9V, ideally 10. You need to measure the voltage at the starter terminals WHILE CRANKING.

For voltage drops, connect the meter between battery + and starter +. Then repeat for battery - and engine ground. Again, measure while cranking. Please note that the losses on + and - sides add up.

Good cabling and battery switch should give you a 1V drop or less. A good battery should hold up to 11V while cranking, leaving you a healthy 10V at the starter.

In my case pretty much everything was wrong. Poor battery cables, an ageing 1-2-both switch, weak battery, ageing ignition switch, poor quality wiring to the solenoid.

So I now have new 2/0 battery cables from Genuinedealz.com, a new ignition switch, new wiring to the solenoid, a new 1-2-both switch from Blue Sea Systems, and a new group 31 battery from US Battery. Very healthy voltage at the starter now.

But guess what? The intermittent start problem was still present. I replaced the starter motor, all is good so far. Will need 6 months of use before I declare it fixed!

 

[MarkSF]

I disagree. The starter solenoid doesn't use much current. That is why there is a solenoid there to start with. If the voltage at the solenoid isn't as high as it should be there is a wiring problem to or from the panel, either gauge, connections corroded, or age of wire. Adding a relay (really another solenoid) will not solve the problem only mask it and add more connections at the same time.

Now if there are glow plugs and they are powered off the panel a relay does make sense as they do use a lot of current.

I agree. The starter solenoid IS a relay. So you're adding a relay for a relay. Will that relay need a relay too?

 

[MarkSF]

Now if there are glow plugs and they are powered off the panel a relay does make sense as they do use a lot of current.

My Universal was wired so that the start button is only energised via the glow plug switch. The problem with that is, you have the glow plug current dropping the starter solenoid voltage!

I have rewired it so the two are separate.

 

[travlin-easy]

I strongly suspect the problem is with the starter, thus explaining the higher than normal voltage drop and battery load-down. Marine starters are not any different that an automobile starter. There's nothing to prevent corrosion causing moisture from getting inside, and in the damp environment of a boat's engine compartment, it doesn't take long for the process to begin. The only method I know to control that environment is to install a good ventilation system, which in my boat is a 72mm computer fan that runs pretty much constantly, but uses very little electricity. It draws just .04 amps, but it moves a lot of air at 12 CFM. Since that fan was installed, my engine room corrosion problems have ceased to exist. The fan cost me a whopping $7 from Amazon.com.

Good luck,

Gary

 

[Capt Len]

Take an old solinoid apart to see that the two bolt ends that are the terminals are corroded. More important is the copper end of the moving part. When it pits up too bad it may or may not connect across the bolt ends and can be temp sensitive. (Click,click) If you turn it 90 degrees you can get some more life out of it .That's pretty haywire. but I've done it in the snow up a logging road.