Bad Starter Relay?

[DanielC]

To check voltage drop, you take the positive (red) lead of a volt meter, and put it on center of the positive terminal of the battery, and put the negitive (black) lead on the top terminal of the starter solenoid, with the red cable on it. Before the starter is energized, the voltage should be 0 volts. The voltmeter is just connected to the two ends of the same wire that goes from the battery, under the floor, past the motor, and up to the "not really the starter relay" , and back down to the starter. When the starter is engaged, a lot of current (amps) flow through this cable, and it has to have a good connection. If there is a poor connection, there will be a large voltage drop in this wire, the starter will not get the voltage it wants, and won't work. The same conditions apply to the ground wire back to the battery.
To turn the motor by hand, you need a 15/16, 1/2 square drive socket, and a breaker bar. A breaker bar is a bar about 18 inches long, and has a 1/2 inch square that fits the socket. The socket should fit on the nut in the center of the bottom pully. on the front of your engine. Looking to the back of the motor, turn the motor clockwise with the breaker bar. It should turn with moderate hard difficulty, but it should turn. MAKE SURE THE KEY IS OFF AND OUT OF THE IGNITION, OR BETTER YET THE BATTERY IS DISCONNECTED WHEN DOING THIS! I am sorry if this sounds too basic, but you said you are new at mechanical things.

[MrMarbles]

Well, I tried charging the battery overnight, just to make sure to rule out the simple things. Still no luck.

Daniel, what you're saying is that I need quite a long cable for my volt meter since my battery is up front? Like I said before, I've put the volt meter on either post of the "not really the starter relay" relay and it read 12V while in "Run" but it drops to 1V when the ignition is in "Start". Is this to be expected or not?

[rocco]

Bad Starter Relay?

I would try a NEW Battery,,,check the Connections good and make sure there tight....You may need to replace both Cables,and get bigger ones to carry the current,, I still think the Battery may be Bad.....

[MrMarbles]

RE: Bad Starter Relay?

The battery is only two months old, but that will be the next thing I test out.

[DanielC]

RE: Bad Starter Relay?

Yes, long cable on voltmeter. it carries very little current to the voltmeter, so small guage wire is ok. make sure that one commectin of the voltmeter is on the battery post, quite common for a bad connection to exist between the battery post and the clamp on the end of the cable.
The volt meter should not drop very much at the "not really" starter relay, reading from the large red cables to ground

[DanielC]

More checks with voltmMeter. This appears not to be a "usual" problem.
You could use someone to help you with these tests. Have you tried to turn the motor by hand, yet?
1. battery voltage: Check with voltmeter on the center of the two battery posts. If the battery just was taken off a charger, it might be as high as 13.5 volts. Check while trying to crank engine also. If the engine starts, and does not have water to it, turn it off immeadeately. Two voltage checks. What were the voltages?
2. Battery voltage at the battery cable clamps, put the voltmeter leads on the clamps, not on the posts. Check with engine off, and trying to start. What were the two voltages?
3. Battery voltage at engine end of battery cables. Put voltmeter leads on the silver looking ends of the cables. The red one is on the "not really starter relay" it is the thick red one that does not go to the starter. The black battery cable goes to a bolt on the block, near the raw water pump on my GT-40 engine, put the voltmeter lead on the silver looking end of the cable. What were the voltages with the key off, and trying to start to motor, two voltages.
4. Block ground: move the black voltmeter lead to some bare metal on the engine block. Check with key off, and trying to start. What were the two voltages.
5. Battery voltage to "not really starter relay" Put the red voltmeter lead on the center of the big terminal of the "not...Relay" that has the two big red, and one smaller red cable. This is not the same place as check #3. check with key off, and trying to start. What were the two voltages?
That is ten voltages. let me know, and I think we can get this figured out. Have you tried to turn the motor by hand?

[MrMarbles]

I have not been able to try to turn the motor by hand yet. I am at work all day, bah! I've done a couple of those tests already:

1. Tested before charging 12V "on", 12V "start"
2. Same as 1
3. 12V "on", haven't tested "start"
4. 12V "on", haven't tested "start"
5. Will check

Thanks for all your help so far!

[DanielC]

MrMarbles, what I am having you do, in case are not following my troubleshooting reasoning is this. I am having you test each individual part in the starter circuit all the way from one battery post back to the other one. Please bear with me.

[MrMarbles]

Hey Daniel,
I was out of town for the holiday weekend and just got to work on the boat some more yesterday. After testing all the voltages, it seemed to me to be a problem with the starter. I would get 12V all the way to the starter, but even bridging the terminals on the starter wouldn't do anything. So I removed the 2 month old starter to test it and noticed that both of the bolts were EXTREMELY rusted. I used some oil and a wire brush and got those things shiny again. Once I put them back in, the boat cranked right up!

What I'm guessing happened was, there wasn't enough connection to handle the flow during start, even though it tested ok when it was in "run".

At least I got a backup "not a starter relay" relay out of it. That and a lot more knowledge of the electrical system.

Thanks for all your help!

[DanielC]

Glad to hear your boat is running again. I am sorry you had to change the "not really a starter relay", but you now have a spare. Having a spare, and the tools, and the knowlege to change it probably means your relay in the boat, will never go bad. On the other hand, you now know more about your boat, and you most probably saved money over having the local dealer teoubleshoot your boat.
I probably have another two months before I will get my boat out.

[Beech67]

Hi, I'm having similar issues. I have a 1998 Sport Nautique with a Ford GT-40 motor. I replaced the starter relay but before I did that, I took photos of the wiring. After reconnecting the wiring, I attempted to reconnect the negative to the battery and it started to spark. I redid some wiring in case I did it wrong and the battery still sparked. Does anyone have a wiring diagram?

[NautiqueJeff]

[Fast351]

Here is another interesting failure mode (if you can call eating a $250 starter interesting)...

I had a problem with my 2001 a couple years ago where you'd hit the start button and all you'd get is a click. This was on a Sunday. After a little troubleshooting I determined the starter relay pictured above to be the culprit. The only thing open on Sunday around here was an O'Reilly's so I bought a relay that was same form/fit/function, but pretty generic looking and probably made in China.

Fast forward to a couple weeks ago. Wife and I are out after a couple cocktails and I'm running the boat up and down the lake at WOT. Were going to sit for a bit and hit the stop button. Engine kept running but dash went dead. Uh oh. Opened the doghouse and it smelled like a giant electrical fire. Got the boat on the lift and it died before I needed to run and grab a wrench to yank the battery cable. It was running pretty rough but couldn't figure out how to shut it off.

Diagnose bad starter, and replace it to the tune of $250 (yes I know you can buy them online for $131, but it was a Saturday and a boat dealer 5 miles from me had it in stock). Replace it, all is good. About a week later my ski partner and I just finish our two sets and we get ready to head back to the dock when I hear what sounds like the blower running. Turns out the starter was still engaged! Limped it back to the lift at idle, and same thing, wouldn't shut off.

So I figured either the ring gear was screwed and holding onto the starter, or something else. Well the boat not turning off with the dash or even the lanyard was the clue I needed. I looked at the schematics and determined it had to be the starter relay sticking on, as that would keep the boat running and keep the starter engaged. Replace it this time with a good NAPA brand (Echlin) one, which looked like much better build quality.

But if you ever have the boat not shut off when you hit stop or turn the key off, it's this relay, and the starter is still engaged more than likely. Do not run the boat at RPM. It was dumb luck that it happened to me when I was idling back to the dock. My guess is that a gear reduction starter is at least spinning 20x the speed of the engine. That means at 3500 RPM it's spinning at 70K RPM!!! No wonder the old one cooked.