Auto/boat electrical dilemma!

[Boomyal]

Last season I had several no crank issues with my boat after I shut it off during the course of people exiting and re-boarding the boat. All the while everything else worked, ie, gauges, blower, bilge pump, etc. I would fiddle around with the battery connections (there was not even any solenoid activation) and cycle the ignition switch repeatedly and invariable it would finally crank and start. It was apparent that something more was going on than met the eye.

As these kinds of issues can go from intermittent to permanent I decided to locate all the pertinent choke points so that when an episode occurred on the water I would know exactly how and where to trace it down. You cannot learn these things when you are bobbing around on the main with a boat load of people and gear.

I have not had the boat out yet this season and I have been slow to research and outline my battle plan. Today I got to it as I have a boating adventure planned for Labor Day weekend.

For starters I fashioned a shunt to be able to quickly by-pass the neutral safety switch inside of the throttle/shift control. I also located and verified power to the ignition/gauge/accessory terminal on the back of the ignition switch. Then I identified the starter terminal on the back of the ignition switch (there are only three terminals on the back if the switch). To verify its receiving power I rigged up a test light so that when I turned the key to start, it would light the test light which was in a location that I could see it. I also obviously identified and verified the power feed to the ignition switch.

I had not yet turned the key all the way to 'start'. With all the battery terminals freshly cleaned and re-anchored, I turned the key to start. Immediately my test light flashed on, the starter made a brief advance, then it quit and the test light went out. Also the instruments and accessories ceased to work (a new situation) I crawled back under the dash with my test light. I verified that I still had power to the ignition switch but I no longer had any power to the ignition/gauge/accessory terminal. I also reached up and turned the key to start and did not have any power to the starter terminal.

Seemingly a clear indication that the ignition switch had been the culprit all along. I never did get further down the line to identify the pertinent terminals on my double starter solenoid setup. I figured that that would not be necessary at this juncture.

Herein lies my dilemma. I was getting ready to disconnect the battery, remove the wires on the back of the ignition switch then remove the switch from the dash. However I decide to run one more test. I crawled back under the dash with my volt meter. I verified that there was no voltage on the starter terminal when the key was turned to the start position, I did verify that I still had 12 volts to the feed line to the switch but while testing that voltage, when I reached up and turned the key to start, the voltage dropped to 2 volts. Again, this is on the constantly live terminal to the ignition switch. I would release the key from the start position and that terminal would return to 12+ volts.

I then hooked a remote starter switch between the constantly live power terminal to the starter terminal figuring that it should activate the starter. Nothing happened when I hit the button on the remote starter switch.

I can't figure this out It has me stumped.

 

[MTboatguy]

Sounds like you have a solenoid shorting out. I would double check that and I would replace the ignition switch.

 

[bruceb58]

You have resistance between the engine and the ignition switch. The wire that feeds your ignition switch goes through the large engine connector back at the engine. I would be checking the corrosion in that connector first.

I really doubt its your ignition switch since you are having voltage drop to the input of the ignition switch. In addition, iff you had anything shorting out, you would be blowing a fuse so that isn't your issue either.

Easiest way to check for a voltage drop is to connect your voltmeter with long test leads between the two points. You can put one lead on the positive side of the battery and the feed side of the ignition switch and try starting. The meter should read close to 0V even with a load on the circuit. In the case where you were measuring 2V at the input tof the ignition switch, you would be measuring 10V during this test.

 

[bigdee]

I had the almost identical problem 2 weeks ago on my pontoon. Turned out the battery cable insulation had a pinhole in it and water had caused it to corrode away to the point that it was creating a large enough voltage drop to prevent the starter from operating. I found the problem by using a jumper cable to shunt from battery to supply side of starter solenoid.

 

[Boomyal]

....... The wire that feeds your ignition switch goes through the large engine connector back at the engine. I would be checking the corrosion in that connector first.

....... .

I have two of those large connectors mounted on the back of the engine. Not sure what feeds what but I will separate them and clean them both. What is a good way to clean those small holes in the female side of the connectors?

 

[bruceb58]

a very small round file might work.

 

[MTboatguy]

As far as cleaning them, electronic stores carry a spray that will dissolve corrosion on connections. I would probably just replace them and then coat with dielectric grease and start out with completely new connections. It seems as if the electrical connections on boats are some of the worst types of connections to keep working good for a long time, the vibrations seem to break connections in all kinds of little places that can be hard to find.

 

[bruceb58]

You really suggest replacing the 9 or 10 pin engine connector?

 

[Boomyal]

As far as cleaning them, electronic stores carry a spray that will dissolve corrosion on connections. I would probably just replace them and then coat with dielectric grease and start out with completely new connections. It seems as if the electrical connections on boats are some of the worst types of connections to keep working good for a long time, the vibrations seem to break connections in all kinds of little places that can be hard to find.

Those two connectors are a real PITA to get to. They are at the back of the engine on a bracket suspended off the intake manifold and under the fixed transom shelf. I do now have them removed and separated but they are on short tethers and hard to get out into the open to futz with.

As far as replacing them, that would be a monumental project as they are are molded into the wiring harness. I must have had them apart once before as I can see evidence of dielectric grease on the male pins of one of the connectors.

I do have some electrical contact spray that I will apply. They do not look too corroded. I will try to find a wiring diagram to see which of the connectors carry the juice to the ignition switch.

 

[Boomyal]

You really suggest replacing the 9 or 10 pin engine connector?

Gulp!

 

[bruceb58]

Probably the biggest contact in that connector is the one that feeds your console fuse panel which therefore is also the one that supplies voltage to the ignition switch. What feeds that connector is the connection down at the starter. I know you said you cleaned that one down at the starter but you need to double check it.

 

[MTboatguy]

You really suggest replacing the 9 or 10 pin engine connector?

I must reading something wrong, I read it to say he was talking about 2 or 3 connectors.

What motor is this so I can look up in my books?

 

[Boomyal]

Probably the biggest contact in that connector is the one that feeds your console fuse panel which therefore is also the one that supplies voltage to the ignition switch. What feeds that connector is the connection down at the starter. I know you said you cleaned that one down at the starter but you need to double check it.

I see the big pin in the left connector. It is a black connector with 10 or 11 pins. The other connector, which is the same size but it is yellow. It only has 5 pins in it. I did not check or clean any connections down at the starter. I will do so.

I did spray both connectors and put them back together, reconnected the batt and tried the key. No luck. Still no starter or gauge activation. I then remove the ignition switch, just to check it. It seemed to be good. I used the ohm meter to test continuity between the Batt terminal and the ignition terminal, then between the batt terminal and the starter terminal, then verified that I still had ignition continuity when in the start position. So you were right about the ignition switch. Just for grins I was going to hook a long cable between the Battery and the gauge ignition wire to verify that that feed to the gauges did work.

This is where the complexity of having two 'starter' solenoids comes in. Years ago I replaced the big old clunky OEM starter with a mini PMR gear reduction starter. It had it's own solenoid. So the OEM OMC Starter solenoid just became another switch. The main battery cable got moved from the OEM solenoid down to the new Starter solenoid. I have a wiring diagram for that change in the glove box. I will have to to check all the connections. Whew! Still cannot quite see how a bad connection at a solenoid would affect the gauges when enough juice is getting thru to the ignition switch to initially show 12 volts at the Batt Terminal on the switch?

 

[bruceb58]

Go through all your connections again. Sand paper them so they are down to bare copper and reinstall.

If you have enough voltage drop to keep the starter solenoid from engaging, what happens when you have something on like your blower?

 

[Boomyal]

Go through all your connections again. Sand paper them so they are down to bare copper and reinstall.

Am reinstalling the ignition switch now, bruce....and sandpapering all the connectors. I will be going back to all the solenoid connections and doing them as well.

If you have enough voltage drop to keep the starter solenoid from engaging, what happens when you have something on like your blower?

That's part of the mystery in that with 12v to the ignition switch I still have no gauges, blower, bilge pump or tilt from the control panel, with the key in the run position. Last year's on the water intermittent no start situations never lost those functions. Now the first time this season that I turned the key on to 'run', I had gauge deflections, tilt and all the rest. The first time I turned the key to start, I had momentary functions (including a brief starter engagement, then nothing. No starter, no panel functions, all with 12v still registering at the batt terminal on the ignition switch. (except for the reduction to 2v, at the batt connection, when the key is turned to 'start'.

What I did not do was to see what happened to the voltage on the switche's batt connector when I just turned the key to 'run'. I will try that post haste.

 

[Boomyal]

Ok, I checked the voltage at both the Batt connection on the ignition switch and the Ign output terminal on the switch with the key in the run position. Both were at 2v. I guess that is akin to a 12 gpm pipe with a restriction in it that will only allow 2 gpm to pass thru it. Now it's on to the back of the boat to find where that restriction is? I will find the power feed to the large pin in the 11 pin connector and check and clean all the connections.

This is gonna be fun as I am not double jointed and I will hate it if I have to tear out all the rear seat panels to get to the connections.

 

[bruceb58]

While you are cleaning these, really examine them carefully for corrosion that may have gone up the wire itself.

 

[MTboatguy]

Hey Boom, perhaps, I can give ya a hand, I will be coming back into Vancouver next weekend, need to give Dad a hand on things, so I am again, heading to the big city. Since your trip is over Labor Day, I will be there a week before that and can bring diagnostic tools if needed, I should be there through Sunday the 6th so we could get together.

 

[Boomyal]

Ach du lieber! I have been fooled by lack of depth of experience. At least I got some overdue 35 year terminal maintenance done and added another nugget of experience to my roster. The 1975 Gulfstream roared to life at 4:45 pm. What an odessey. I am worn out from kneeling, squatting, reaching, laying on my back, climbing in and out of the boat to grab various tools and supplies and hooking up meters and lites, then doing it all over again.

After having removed 5 terminals from the OEM starter solenoid and reaching out to the end of my reach to clean each terminal (they were not brilliant clean, I still had no power to the dash. I went back and put the test light on the solenoid stud that I had just cleaned all the terminals thereon. No power. Now I am really scratching my head. I traced the big red cable back to the battery and put my test light on the battery post. There was power. I moved the test light probe over to the marine terminal affixed to the battery post. No juice. I removed the battery and put it on the bench and removed the marine post terminal. I had cleaned it previously and it never did look good, but I had scrubbed it and wire brushed it into oblivion. Over the years I have cleaned many a terminal when the were dirty enough to keep a car from starting.

Both the inside of the marine terminal and the positive battery post had some kind of hard, black, crystalline coating on them. It would not wire brush off or sand off. I ended up having to scrape the battery post with a knife blade to break it off. I had never seen anything like it. I took a pocket knife blade to the inside of the marine terminal but could not get it to clean up. So with a finally clean battery post I went down and bought another marine terminal. I put it on, reinstalled the battery, hit the key and voila, a full dash display with working tilt. This had been the source of my intermittent problem last year. It was so acute that it would not even start up when I set out to ready the boat. This could have easily left me stranded several different times but held on for just long enough for it to fail in the driveway.

I removed the spark arrestor, squirted a couple of tablespoons of gas down the shute, hit the key and the old bugger fired right up and ran like a swiss watch.

Thanks all, for holding my hand thru this and giving me the confidence to persevere. Now to go out and put the bucket full of tools back in the garage in the various and proper locations..




.

 

[Boomyal]

Hey Boom, perhaps, I can give ya a hand, I will be coming back into Vancouver next weekend, need to give Dad a hand on things, so I am again, heading to the big city. Since your trip is over Labor Day, I will be there a week before that and can bring diagnostic tools if needed, I should be there through Sunday the 6th so we could get together.

MT, I was a hair's breadth away from gladly accepting your offer. However, per my post above, you can leave your diagnostic tools in the trunk. BUT I would be mighty disappointed if after another trip to the 'big (smokey) city' we did not have the opportunity to meet up. Give me a holler!