Mercury Force 120 With Power, But No Crank *Video Inside*

[AirOPS]

Hello everyone,

First time poster here, and first time boat owner, as well.

I've set my boat in several times over the past few months, and the motor actually runs great with no hiccups whatsoever from startup to shutdown. However; it has always, upon first crank, turned over quite slowly at first, and then suddenly would "speed up" and immediately fire up. I've always attributed that issue to the Force 120 being a high-compression motor, taking plenty of juice to get turning. I tried to set in today and encountered the same old slow turnover, except that this time it didn't speed up and fire up. Sounds just like a nearly dead battery... that signature "Whir.... Whir Whir..... Whir" sound.

It's always plugged in while in storage via its Minkota charging system. When I left for the lake house Friday afternoon, both batteries had green Full Charge lights illuminated. It has sat for only 2 days unplugged, so initially I figured the battery is actually bad, and doesn't hold the charge if it sits unplugged for more than a day. The only problem, as you will see in the video below, is that even hooked into "house power," the same slow turnover occurs.

Please view this video, for your considerations:

I can't make any sense of this. Unlimited power from the wall outlet, yet it's apparently not enough to turn the motor over? Granted, I have a LOT to learn about marine systems, and so I won't mind criticisms. Thanks for any help, friends.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

**QUICK UPDATE**

Okay so it had been sitting on the charging system for about the past hour. Right after posting the thread, I went outside and it turned right over! So does this mean that the Minkotas aren't designed for "jump starting" off house power, and only allow general battery charging to occur? It's quite apparent that the battery doesn't hold charge for more than a day or two, now. Thoughts and comments? *I'm learning, guys *

 

[Jiggz]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

I am suspecting three things causing your problem. From the easiest to the stubborn ones: although a discharged battery can also be the cause of the problem. It looks like the charging unit you had is not large enough to provide starting power. You could have jumper the battery with your car battery and tried the starter again. Anyways, try this for troubleshooting.

1. Loose or dirty wire connections. I'm referring to the big red cable that connects from the battery to the solenoid and then to the starter. And also included is the negative big black cable connected from the battery negative terminal to engine ground.

2. A faulty solenoid

3. Starter needs cleaning or starting to fail

Solutions:

Disconnect said cable, clean them until they are shiny clean and reconnect tightly. And then do the following tests.

Test the solenoid but jumpering the two big terminals and see if the starter cranks over well. Do this a couple of time. If it does, then you can presume the starter is working well but not necessarily the solenoid. Otherwise, the problem is the starter which you can dismount, disassemble and clean. Re-install and test again.

Test the Solenoid by jumpering its coil terminal (small red terminal) to the big red terminal connected to the battery (source or power side). This is better done with alligator clips wire or small battery jumper. If the starter cranks well, then you shouldn't have a problem doing the same test with the ignition switch. It could be that the original problem was caused by loose or dirty connections. However, if the starter will not crank with this test, then it means the solenoid has either worn out contacts and needs replacement.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

I am suspecting three things causing your problem. From the easiest to the stubborn ones: although a discharged battery can also be the cause of the problem. It looks like the charging unit you had is not large enough to provide starting power. You could have jumper the battery with your car battery and tried the starter again. Anyways, try this for troubleshooting.

1. Loose or dirty wire connections. I'm referring to the big red cable that connects from the battery to the solenoid and then to the starter. And also included is the negative big black cable connected from the battery negative terminal to engine ground.

2. A faulty solenoid

3. Starter needs cleaning or starting to fail

Solutions:

Disconnect said cable, clean them until they are shiny clean and reconnect tightly. And then do the following tests.

Test the solenoid but jumpering the two big terminals and see if the starter cranks over well. Do this a couple of time. If it does, then you can presume the starter is working well but not necessarily the solenoid. Otherwise, the problem is the starter which you can dismount, disassemble and clean. Re-install and test again.

Test the Solenoid by jumpering its coil terminal (small red terminal) to the big red terminal connected to the battery (source or power side). This is better done with alligator clips wire or small battery jumper. If the starter cranks well, then you shouldn't have a problem doing the same test with the ignition switch. It could be that the original problem was caused by loose or dirty connections. However, if the starter will not crank with this test, then it means the solenoid has either worn out contacts and needs replacement.

Thanks for the response Jiggz!
I've noted your troubleshooting points for future problems as they arise. As it were, the Minkota has two green lights right now, and the motor turns over REALLY quickly and fires right up. This leads me to believe that every time I've experienced a slow turnover, it has been a direct result of my battery being low on charge. This is in spite of me keeping the boat plugged in when n

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Thanks for the response Jiggz!
I've noted your troubleshooting points for future problems as they arise. As it were, the Minkota has two green lights right now, and the motor turns over REALLY quickly and fires right up. This leads me to believe that every time I've experienced a slow turnover, it has been a direct result of my battery being low on charge. This is in spite of me keeping the boat plugged in when n

in when not in use. So, I've come to the conclusion that the battery is simply not holding a charge for more than a day or two when unplugged from the charging system. **Also, i can run up and down the lake till the motor is good and hot, and shut it down, and then it'll crank right back up every time. I'm gonna get a nice new marine battery and go from there. Thanks for all you're input!

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

While I have this thread active, what do you guys make of the fact that my main power cables are hooked into the accessory posts along with all the accessory wires??

Is this safe??

 

[emoney]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Check the CCAs on your battery too. If you're going to buy a new, but one rated for over 700 CCAs at least (COld Cranking Amps). Not familiar with your exact charging system, but I've found that several of them I've had over the years are more like "maintainers" or "trickle chargers" at best.

As for all the accesory wires, I wouldn't want that set-up you have. It's not that hard to run all the wires to a fused terminal block, along with a grounding strip. Not only will it clean things up, but then you only have the one main line back to your battery. You can still hard wire in a float switch for the bilge pump, for safety sake. But I'd definitely put a "power center" in. They're not that expensive and not a hard job to do.

 

[Jiggz]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

While I have this thread active, what do you guys make of the fact that my main power cables are hooked into the accessory posts along with all the accessory wires??

Is this safe??

You might want to look further because usually, there is an accessory wire from the battery and then feeds into a fuse panel under the dash. And then there is the main starter big red cable which goes directly into the solenoid.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Hey thanks for all the replies folks. I'm gonna start by picking up a new battery and go from there. Just now right before sunset, the wife and I had the trailer/boat in the water and everything, fresh off the charging system. Nothing. Slow crank, no start. Disappointing. It obviously needs a new battery. Will update after a fresh battery install.

 

[emoney]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

If you're replacing both batteries and don't already have a 1-2-Both switch, it might be time to consider one. Sure does help avoid some of those "no-start" moments. Also, since it looks like everything was wired straight to the battery, you may have something draining it as well. Also, make sure you don't have a battery that needs maintained with distilled water.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

emoney:
The gentleman I purchased the boat from said the only drain issue he had was the stereo (it's a fish and ski), and to fix that, the stereo was put on an isolated toggle switch. The vessel does have two batteries. The other one has the trolling motor and stereo hooked to it. Now, with all the accessory wires coming off those accessory posts, I gotta say that each one does, indeed, have an inline fuse..

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Gentlemen:
So for the past two days I've let the boat sit without being plugged in to charge. The objective, of course, is to monitor the battery for discharge. Nada. It has maintained 12.5 volts. So the real test: I cranked it while holding the volt meter to the battery, and it's delivering 7.4 volts, turning the motor very, very slowly. All the research I've done says that anything below 9 volts while cranking indicates dead cells; i.e. a bad battery. What say you?

 

[emoney]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Or a bad charger. I'd still look in on the starter to be safe.
On a side note, when you get this straightened out you should really think about going with a wiring panel/box.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

TIme to pull that starter off and have a look inside it and see what's going on. Those starters are fairly simple to rebuild and not that expensive to replace.

On a side note, when you get this straightened out you should really think about going with a wiring panel/box.

emoney:
Can a faulty starter cause a battery to deliver low voltage on crank?

 

[emoney]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Sorry Airops, I edited my post. Having a little "focus" issue.

Unless you suspect there's a chance something's wrong with your meter, then the battery has issues for sure. SOme of them come with a 2 year warranty, so check the dates just in case.

Out of curiousity, did you check the CCA rating on the top/side of the battery? I did have a boat that a PO had put a too small battery in, it was a SPortJet so same head, and when I exchanged it for one that did higher cold cranking amps it solved my issue. Something to look at so you don't replace with another one and that be the issue.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Man surprisingly the starting battery CCA is rated at 1000, which upon seeing, I said to myself "Well that seems to be a tad bit overkill.."

 

[Jiggz]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Man surprisingly the starting battery CCA is rated at 1000, which upon seeing, I said to myself "Well that seems to be a tad bit overkill.."

Not really, unless you cannot afford the price or it will put a big dent on your budget. With marine batteries, the larger you can afford the better is your chance of having extra available current from the said battery especially in an emergency. To validate the battery status, switch it over to another engine like a car or truck and see if the problem is the same. If it is then the battery is in need of replacement. Or if you do not have another engine have the battery load tested at Auto Zone.

 

[emoney]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

I went with 900 on mine, because like Jiggz said, you can't have "too much". Let us know when you get the battery test, pretty sure Auto Zone does that for free.

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Hey guys,
Just got back from AutoZone. Sure enough, tester said "Replace Battery! Bad Battery!"

 

[AirOPS]

Re: Mercury Force 120 With Power, But No Crank *Video Inside*

Gentlemen,

Just to briefly bring this thread back to life after so many dang months, I want to make it clear to everyone that the issue ultimately was just a bad battery. I know this thread was long and drawn out and covered several bases, but it's one of those situations where you just breathe a sigh of relief in the end to know that it was the simplest of fixes.

Were there lessons learned? Hell, I dunno... but I guess the moral is to never doubt the finality of a legitimately failed battery. I guess that's all I have to say, but I felt as though this thread needed some closure for any boaters out there who come across a similar situation, especially those who are just "POSITIVE" they have a legit battery