Force 120 starter problem

[Spinkick]

I posted this on another forum, pardon if anyone has seen it twice now...

Howdy... new to the forum.
I have a 1998 Nitro Sport 185 with a Force 120. A few weeks ago I had a slow turning starter that I swore was the battery. I replaced it and still had the issue. Ultimately, I pulled the starter and took it apart. I was quite surprised to see the grease and grime build up INSIDE the starter. I cleaned it up and bought a new endcap with new brushes since the insulator was broken. I ran fine next time I took it out with whole family. Instant starts...no issues.

Took it this past weekend and got it off the trailer and parked it at the dock to move my truck. It had trouble running (cold) then out of the blue started the slow starter crap again. Needless to say the fishing day was over then.

Took the starter back apart and all looked ok except some of the epoxy(?) on the windings appeared to be burnt and cracked. Otherwise it looked fine. I found a fairly new starter on ebay so i bought it and am waiting on it. Is there ANY other ideas in case this starter fails to solve the issue? I don't mind taking it in but I hate the thought of it being something I could handle myself.

Secondary question, I had to have a complete rebuild of my motor last year (previous owner was not the sharpest knife in the drawer). It has run fine (barring the starter quirk) but just never had good speed. 43mph (GPS) is the BEST i could get. Finally put compression tester back on and read 80 on each cylinder! I about fell out. Will test with another tester, but wanted some insight or input.

Was told slow starter can skew the compression test, so I'll do that again later. Battery info... fully charged (12.6v on both starting and trolling), connections solid with no corrosion. Charger, voltmeter, and LED tester all say batteries are full.

Thanks for your time
Brent

 

[eurolarva]

Re: Force 120 starter problem

With the insulators melting chances are some are shorted together. Force tends to be hard on starters. People are not educated on the proper starting procedures and because of it they really put a large drain on their starters. I would not let it crank more then say 5 seconds without a cool down. Compression should be over 100. When doing this you should have all the plugs out and grounded or the landyard pulled so spark is nulled. Cant help with top speed but 43 sounds pretty close to me.

 

[JB]

Re: Force 120 starter problem

"connections solid with no corrosion"

Not good enough, Spinkick. It only takes a few milliohms of corrosion in the battery ground cable to block connection to screw up the operation of the starter. Take them all off, clean them and reattach.

Not getting enough current is very destructive of starters. You have been fixing symptoms, not causes.

Let us know what happens.

 

[Spinkick]

Re: Force 120 starter problem

"connections solid with no corrosion"

Not good enough, Spinkick. It only takes a few milliohms of corrosion in the battery ground cable to block connection to screw up the operation of the starter. Take them all off, clean them and reattach.

Not getting enough current is very destructive of starters. You have been fixing symptoms, not causes.

Let us know what happens.

Thanks for the replies.

I agree about the resistance on terminals. All terminals are coated with dielectric gel for that reason. When I check the voltage I check directly on the post first THEN I confirm I get the same checking the connectors. Besides, the starting battery is new. The day I described was its second day of use.

As for the symptoms, the starter was the first problem because of the grime inside was binding the starter. After cleaning then replacing the brushes all was fine. I'm hoping the damage to the starter had already been done. Nevertheless, I get my semi-new replacement starter this friday so we will see.

Thanks again for the input.

 

[Spinkick]

Re: Force 120 starter problem

OK .... "new" starter received and problem not solved. To eliminate the battery directly being the problem... one battery measures 12.3v the other 12.7v. When i hook them up and measure at the OTHER end of the cables, i get 12.3 and 12.7.

Unfortunately I don't know enough about outboards to know what I should do next barring expensive service. Are there any other simple tests?

To describe in better detail, when i turn the key to start, the starter turns the flywheel about 30degrees and stops. Bumping the key again does the same thing. It just turns about 30deg and stop. If the battery wasn't new, I'd swear that was it.

I appreciate any additional ideas.

 

[eurolarva]

Re: Force 120 starter problem

Are the starter wires getting real hot? Rebuilt or slightly used starters scare me. Ebasics sells aftermarket starters for a reasonable rate and you can usually get a new one on ebay for decent price. Battery with no wires hooked up and sitting at least 4 hours after charge should read about 12.65 volts. If in doubt see if NAPA will load test it for you.

 

[JB]

Re: Force 120 starter problem

Starter (series wound DC) motor basics:

You have 12.6 volts DC at the battery with no load. There is some internal resistance, so when you load it by engaging the starter the voltage available at the terminals drops. If the battery is healthy that drop is no more than a couple of volts. The amount of drop is a function of how much current is being drawn from it. A healthy starter circuit may draw as much as 300-400 amps, which should drop battery voltage to 10-11volts.

If battery voltage does not drop below 11volts when the starter is engaged there is not enough current being supplied to the starter motor. This is a symptom of a resistance in the circuit that is limiting current to less than the starter motor needs to develop starting torque.

If battery voltage drops below 9 volts there is too much current and the starter motor is not turning fast enough to develop counter voltage (counter EMF in twidget terms). This is a symptom of a failing starter or a mechanical overload that the starter cannot turn fast enough.

In "Outboard won't start" in the Engine FAQs are a few simple tests of the starter solenoid, motor and wiring to isolate probable problems.

I still think your problem is caused by resistance in the circuit. You obviously believe that inspection and grease prove the connections good. I have found too many tight and clean looking connections causing trouble to accept that evidence. Voltage measurements with no load on the circuit cannot detect the milliohms of resistance that can disable the starter circuit. Ohmmeter measurements cannot detect it either. It can only be detected by voltage measurements with the starter engaged.

Do the troubleshooting tests in "Outboard won't start" and let us know what you find.

 

[Spinkick]

Re: Force 120 starter problem

Yes sir... when I clean the connections and protect them with the dielectric grease I believe there's nothing left to cause the resistance.

Nevertheless, I did see the FAQ you mentioned after I made that post and did the test under load. First, the solenoid is new...just replaced it a few days ago. With the load on the battery the lowest voltage drop was to 9.7v.

Then I became a little suspicious about the battery wondering if it was REALLY delivering the current it was rated for. I took it back to the parts store and had it load tested. It tested good. It was a 550CCA battery. Per spec 490CCA was minimum. I upgraded to 750CCA Optima. I put all cables AS THEY WERE because I wanted to know the role the battery had in this mess. The motor started immediately.

The real test will be the next couple times it goes on the water. If it lets me down, it won't be the battery or the cables, but something else over my head and it will be time to shuck out the $ to find it.

Thanks for all the input.

 

[eurolarva]

Re: Force 120 starter problem

If you have a hand held volt meter you should probably take it out on the lake with you. If your rectifier is shot your battery may not be recharging and could be giving you a reoccuring problem. If a battery is not kept fully charged at all times it will degrade to the point where re charging it will do no good. When you are under way at more then half throttle you should see a jump in voltage to around 14 volts and when motor is off the voltage should drop back to 12.6 volts. Good Luck.

I did a search on starter problems and a good percentage of the problems deal with bad starters and bad batteries. People swear up and down the batteries are fine but they tend to be the problem in a lot of cases. I bought a brand new marine battery and had nothing but problems where I finally took it back. Chances are it had been sitting on a shelf for months with a partial charge and it would never go back to full charge.

 

[JB]

Re: Force 120 starter problem

"Yes sir... when I clean the connections and protect them with the dielectric grease I believe there's nothing left to cause the resistance."

Not so, Spinkick. The ends of the cables are copper, sometimes coated with tin. Where the ground cable is bolted to the engine block is usually steel, with a steel bolt and nut. Sometimes a steel washer in there, too.

No air or water needs to touch that junction for possible creation of non-conducting films between the copper and the steel when heavy currents flow.

If you have removed and cleaned that connection this is an academic discussion. It is just that I have seen too many batteries, solenoids and starters replaced in attempts to overcome such a simple and easy to fix problem.

 

[Spinkick]

Re: Force 120 starter problem

If you have removed and cleaned that connection this is an academic discussion. It is just that I have seen too many batteries, solenoids and starters replaced in attempts to overcome such a simple and easy to fix problem.

Yes, although I didn't state so, I cleaned both ends of both cables. Been that route with autos.

I do appreciate your insight and advice.

 

[Spinkick]

Re: Force 120 starter problem

Problem definitely solved.... it was the battery. Despite being new, it apparently wasn't delivering its rated CCA.

Thanks to all for the input.