Starter - how to know?

[rebuckley]

Occasionally my starter does not seem to want to cooperate. I am not sure if it was simply sitting all winter, or if the starter may be on its way out? How can I test to see if I have starter issues, starter solenoid issues - or is it something else?
It is on the Lehman 120, and the all the battery hookups were great. Now the batteries were low after the winter - but charged to float overnight. When I hit start, it sounded like I got a half of a crank and then nothing. I did this a few times - letting the charger hit the batteries inbetween attempts. After multiple tries - and getting ready to jump over board - I hit start and brmmm - started right up.
I have not gone back to play - I plan to this week. The batteries will have full charge by then and I can see if that is the simple answer. But thinking back - I did have a time or two last year when the starter sounded like it kicked in, but didn't give a good crank.
Is there a way I can test/inspect the starter and solenoid?

[WillieC]

Learn how to use your voltmeter to read voltage drop across cables, solenoids, battery terminals. etc. Your meter must be set to Volts DC and the right range. Ordinarily, placing one lead on the battery post and the other on the cable termination right next to it, you would read ZERO volts. There is no voltage drop across that connection. (Something in the circuit must be drawing power for this to indicate anything. Turn something on.) You do not need to remove any terminations which is why I like to start here.

If you read say 2 volts, that connection is badly corroded. It may look like gold. Note also that your readings will change under load, and the starter is the big one.

You could do a simple walk through by turning on a bunch of stuff (not cranking) and start at the battery as described above. You may start to see higher resistance connections. I also, when in doubt, will check individual cables, if I can get to both ends. (A jumper wire can help, but may introduce more resistance.)

There is also the issue of battery condition, but skip that for now. You say they charged up, and you think you are good. Go with that until you run out of ideas.

In your case, focus on the starting circuits. (I say plural because you have the low power side that runs the solenoid coil, and the high power circuit that spins the starter.) To test the big contacts in the starter solenoid, it is the same routine, only do it while attempting to crank since the contacts are open at rest. You should read system voltage (i.e. 12V) across the solenoid when open. Figure out a safe way to clip your meter leads onto the bigass terminals on the solenoid. Or have a helper for turning the key while you hold the pointy leads. One comes from the battery, or bus bar, and is HOT, careful. The other goes right into the starter. Hit the starter and, if you hear the solenoid kick in, your meter should go to Zero volts. No resistance across the internal solenoid contacts . Whatever it reads is subtracted from system voltage and that is what is getting to the starter. If the contacts read 2 volts, the starter is only getting 10 volts and will crank slower than designed (if all the other connections are pristine.) This is why clean connections rule the day on low voltage systems. Every one counts. At 120VAC...what's a little resistance? (Well, heat, for one...)

Not trying to overwhelm, this is basic trouble shooting. Just be careful even though it is 12 volts. There are a bunch of amps in the battery waiting for a short circuit.

[Tree]

What kind of starter do you have - the long cylindrical type or the one with side mounted solenoid?

On a previous boat, I had this engine but in the 250 hp variant, I had nothing but problems with the starter sticking despite replacing it numerous times. That was the cylindrical type. Soon as i swapped it out for the one with the side mounted solenoid - problem went away. With the previous one, the number of times I had to tap the case with a lump of lead to make it work was ridiculous!

[rebuckley]

Thanks -
The starter is the model with the solenoid on the side.
Yes - the 12v test is my plan this weekend. Just figured I would ask to see if anything besides tracking the voltage would be worth doing.
Thank you -

[kerrye]

It sounds to me as if the batteries or a battery is bad. It's not often that if a starter gives half a crank that it is the problem. Harbor Freight sells a battery load tester pretty inexpensively. Batteries sometimes go bad when sitting. I'd load test the batteries first.

[RobS]

Observing the voltage drop with a DVM when cranking is the "load test" that applies here. Start at the battery posts and work your way to the starter. If the battery checks good (drops to 10-ish volts when cranking) and the same drop is measured at the starter then the starter is no good. If the drop is greater at the starter than it is at the battery then something is amiss in the wiring.

[jleonard]

FordLehmanEngineElectricSchematic.pdf

Also there is a relay in the circuit ahead of the starter. Mine is located on the stringer next to the starter. Open the attached PDF and you'll see it.
I bought a common auto parts store relay and have it aboard as a spare.

[DesertAlbin736]

You could also do the old mechanics trick of using a remote starter trigger switch connected directly to the starter like this:

aaremotestartswitch.jpg

Clip one lead to the main positive cable terminal on the starter solenoid, the other to the post on the solenoid right next to it that has the small wire coming from the dash switch and/or intermediate relay. If the starter works with the remote switch then your problem is not with the battery or its cable connections between the battery & the starter but is with the ignition key switch, the start push button switch, the relay in between, circuitry upstream and or all of the above. Could be as simple as loose connections to the dashboard switch or a break in the wiring between the dash & the starter. If it still doesn't work & all the other wire connections, switches, & relays check out then the problem could be with the starter itself, or possibly just a bad solenoid. In any case a remote trigger switch like this is handy for things like bumping the engine over to align cylinders to TDC for valve adjustments (with the fuel stop handle pulled).

You could also check the specific gravity of the battery electrolyte with a simple hydrometer if it's a conventional flooded battery to see if that's good & holding a charge.

battery hydrometer.jpg

[Jay Knoll]

Check your ground connections. I just had a similar starting problem after years of trouble free starting — I replaced the start battery in December then this week after a particularly rough crossing of St. Andrews sound the engine wouldn’t start. Went through the entire starting circuit and found a loose ground connection don’t know what caused it because I really cranked down on the terminal connection when I installed the new battery but once they were retightened the engine starts without hesitation

[rebuckley]

I picked up a remote starter, but am not 100% on how to hook it up? The solenoid has the main post with the positive from the battery. I have a relay that has the small "s" wire (starter from the helm red/white stripe). It has 2 other posts, one (on top) is attached to the solenoid where the positive comes in, the other is hooked to a "tab" post on the solenoid. From above my guess is I would be putting one clamp on the main terminal with positive, and the other on the "tab", essentially bypassing the relay?

[jleonard]

Yes large positive lug on the starter to ground.
And if it were mine I would simply replace the relay that is on top of the starter in your picture.
Cheap and it's pretty generic and would be my first guess as the culprit. The large contacts inside go bad.

[rebuckley]

Thanks Jay - I have one to replace it with already - I am betting you are correct. The issue sounds like I have a short or bad ground - so I bet you are right with that being the issue (or if not the issue - one of them). Once the starter gets the juice it cranks fine - so I bet it is good and all of the connections are clean - so the $20 part is being sacrificed!!!

[Panhdjoe]

CAUTION, I am not sure what jleonard means for sure, he is a smart guy. But I must point out that if you connect one lead of the remote starter switch to the main lug on the starter and the other lead to ground when you depress the button there will be lots of SMOKE AND FIRE. it will be a dead short.

[Panhdjoe]

BTW, the remote started switch is used by connecting one lead to any 12v power source, usually the battery or the large positive lug on the starter. and the other to the small "S" terminal on the starter.

[jleonard]

I sit corrected don't know what I was thinking probably cause I just use jumper cables to do a started test. Pos bat to starter lug.
I would still simply change out that old relay and try that before testing.