Problems with Starter Wiring...any suggestions

[Chris Reinke]

I had a GREAT sail over the past 3 days from Cape Cod, around New York and up the Hudson River...except for a starter issue that had me worrying the entire trip.

I have done some trouble-shooting of my Westerbeke M-30 and here is what I have found so far:
- The batteries are fully charged
- The ignition switch is functioning properly
- The glow plug and starter button switches are operating properly
- The starter has 2 wires
(red from battery by way of the amp meter, Yellow/red from starter switch which I refer to as the "control wire")

After sailing for several hours the starter is not spinning or engaging when the starter button is depressed. Jumping the starter switch has no effect. If I wiggle (I know it is not a very technical approach - but it is effective) the control wire where it attaches to the starter the starter will function properly.

So here is the problem. The starter "control" wire is not making a good connection at the starter terminal post. The "control" wire has a simple female spade connector....the kind that every good marine electrician would say not to use. The starter has a simple male spade post which the control wire is held on via friction. I don't see a way to modify the starter to use a bolt on connector, nor do I see a way of upgrading the control wire connection to ensure it does not continue to work itself loose.

Any suggestions on modifying this connection to eliminate the poor contact would be appreciated. I have cleaned both contacts and tried to squeeze the spade connector a bit to ensure a better contact, but the problem remains.

[Boyd]

The wire is probably broken off right behind the connector and making intermittent contact.

Boyd
s/v Tern
CD30 MkII
Fort Lauderdale, Fl

[Ed Haley]

Chris:
I had the same problem on my CD330 a few years ago. The problem turned out to be a poor ground. It was caused by a cracked ground plate that also held the secondary fuel filter and attached to the engine head. I had the crack welded and then it started like a new engine. Never had the problem again.

You may also find the spade connector might interfere with starting. But if, after replacing the connector, it doesn't fix the problem, check the ground.

[richvanheynigen]

Hi Chris,

Had a similar problem on our 28, with a Universal diesel M18. After troubleshooting, replaced the wire, the in-line fuse holder and fuse on the yellow/red wire running from the starter button to the starter. Amazingly, all three were bad. Check to see if you have a wiring diagram in the engine manual. Good luck.

[seadawg]

Chris, I'm not familiar with your particular engine and starter so let me make a few assumtions: Starter gets it's ground where it is mated to the engine block so it is probably ok. The yellow/red wire is most likely a smaller gauge control wire that actuates a relay or solenoid inside the starter itself. When you move that terminal around you are also moving the relay contactor inside. The spade terminal is probably ok and if you replace this connector and still have a problem it is most likely internal starter. I don't know with your equipment if you can get an exchange starter solenoid or if you would need to get an overhaul exchange starter. I hope I didn't have to make so many assumptions that I wound up in left field. Maybe some of these thoughts will help you. Cheers, Charlie.

[Chris Reinke]

Thanks for all the good ideas and suggestions. I had the engine rebuilt 2 years ago and a new wiring harness was installed on the engine side of the gang connector so the wire, 20 amp fuse and spade connector were all new at that time. Since it is an intermittent issue (the kind I really hate!!!) I am not sure how best to try and diagnose exactly where within the circuit the problem exists. I will start by replacing the spade connector to eliminate the possibility of a bad connection at the connector...but then how do I check the wire, fuse holder, or internal to the starter?

I do have the full engine service manual for the M-30, M-40, and M-50 which includes a basic wire diagram. The yellow-red wire is a slightly small gauge (#16) compared to the red power wire (#10).

[seadawg]

Chris, perhaps you can do some checks but you will need a voltmeter but not necessarily an expensive one. You may already have one or they are available at radio shack or others. So with this voltmeter, black lead on the engine block and red lead to the big red wire at the starter you should have approx 12 volts. When you engage the starter the 12 volts should still be there, it's always suppose to be there. You should see it dip some when the starter runs, several volts but thats ok. If the 12 volts is not there at anytime the problem is between the master switch and the starter. Measuring the yellow/red wire with the voltmeter. There are two ways this can work: either the starter switch provides 12 volts to the small terminal or it provides a ground to start. It is probably a ground and if that ground is there (or voltage) and the starter doesn't function then the starter has internal faults. Sometimes if your voltmeter has a sharp probe you can make your measurements at the starter post bypassing the spade terminal to the post itself. Without the wiring diagrams it is hard to second guess the troubleshooting process but good luck to you. Hopefully someone on the board will have better insight than I. Cheers, Charlie.

[Oswego John]

Chris,

Since it is an intermittent issue (the kind I really hate!!!) I am not sure how best to try and diagnose exactly where within the circuit the problem exists. I will start by replacing the spade connector to eliminate the possibility of a bad connection at the connector...but then how do I check the wire, fuse holder, or internal to the starter?

By all means, first check out the things that were suggested. Do you own a multi-meter? If so, use it to check out the power to the starter solenoid. Visually check the wires for breaks at the crimps of the spade connectors. Tug slightly to make sure that the conductor is not loose, but is making good contact with the connector.

Probably the simplest test you can make is by making a jumper wire a little longer than the distance from the battery to the starter. Attach an alligator clip on one end of the jumper wire and skin the insulation off the other end for about 1/4" or so.

Place the alligator clip on the positive (+) battery terminal. This will make the other end of the jumper hot. 12v +.

Disconnect the spade connector. Touch the bare end of the jumper to the male part of the spade connector, the part that goes to the starter. Hopefully, the starter will engage and the engine will turn. You don't have to run the engine. Jiggle the wire to the solenoid between tests. Do this test 4, 5, or more times until you are stisfied that this part of the circuit is in good working order. Reconnect the spade connector.

Next, using the bare end of the jumper, work your way back toward the switch, superimposing a substitute feed for each component in the starter solenoid circuit. Testing the circuit in this manner will usually expose the fault you are looking for.

Not counting the glo-plug, there are two separate circuits in the starter's electrical system. The red/yellow tracer is the control wire which supplies power to the solenoid. The solenoid is an electromagnet which, when activated, closes a much larger set of contacts which provides a heavy amperage feed to the starter windings, which in turn, cranks the diesel engine. The lighter load through the solenoid requires a ground at the starter frame in order to complete the circuit.

The heavier load through the #10 red wire, passes through the starter windings. This load requires a very good contact ground. If the ground at the starter is only so so, the poor ground will only invite starter trouble. A poor ground at the starter is the cause of a high percentage of starter problems.

The ground can be tested by the use of a multimeter. Some people hook up a 12V lamp, neon or lcd bulb in series with the jumper wire and hold the end on the starter frame. I prefer a 12V incandescent bulb to see how bright the bulb gets. A poor ground makes the bulb dim. A good ground makes for a bright glow.

Good luck,
O J