Sometimes Motor Cranks, Sometimes it doesn't - Runs great when it gets started - Why?

[jhouser]

I am confused and really hoping to get some help as I am going boating tomorrow afternoon and would love to have this fixed, so I do not have to worry about getting stranded.

So here's the deal - 88 Johnson SPL (1988). Bought the motor and boat (1988 Stingray Super Sport Bowrider) from a guy a couple of months ago. It started right up for a couple of months. It runs great and strong.

The problem is over the last few weeks it has had trouble starting - as in sometimes when I turn the key it turns over and starts right up, but sometimes it does nothing, just a click. Sometimes I will be trying to get it to turn over for 5 minutes or more. I thought it was the battery connections so I bought new connectors and scrubbed the terminals to a high shine then reconnected everything nice and tight. Thought that would fix the problem but it still does it just like before. Probably about 1 out of 20 times it will crank, the other 19 just a little click happens. Again, once it gets running it runs GREAT.

What could be the problem? Really don't want to get stranded.

Thanks.

 

[oldboat1]

intuition sounds correct (starter circuit -- electrical). solenoid is clicking, but starter isn't getting enough juice to crank the engine. Put a full charge on the battery and try it (or another battery, if you have one). If the fully charged battery won't do it, suspect battery is past its prime (have it load tested), or starter is due for a rebuild (can also be removed and tested). Could be other issues, but think battery/starter are basic if connections are clean and tight.

 

[Fed]

Have you watched it to see if the starter motor is spinning, you could have a sticky Bendix not rising.
Have a look before you go any further.

 

[jhouser]

Thank you for the two suggestions oldboat1 and Fed!

oldboat1, I have put a full charge on it and the issue persists. In fact, while at the dock I took the battery out of my 2014 Ford Explorer and the same thing happened with the Explorer battery, it would click sometimes then it cranked hard, then started right up. Ran great all day, except for when it was turned off, the problem came back. Then it started and ran great again. Also, I have had the battery tested and it is good - it is rated at 800 amps and it reads about 750 at Autozone. Fed, that is a very interesting idea, maybe the bendix is not rising, I had never thought of that and will definitely check that out!

I think a good option is to clean all connections. I was just reading on another forum post I found through Google, when the issue is happening, take off the motor cover and lightly touch all connections (not when the key is on or the motor is cranking - being shocked is not fun); if there is a hot connection, that is likely where the bad connection is, because it is creating an arc. And one should clean that connection extra well and make sure it is tight. I will do this tomorrow, and I will also check the Bendix to make sure it is rising that could very well be the issue.

If anyone else has any ideas I am all ears and open to suggestions. I am not sure if this is common with Johnsons or all motors at times?

Thanks.

 

[interalian]

Assuming the 'click' comes from the motor and the starter isn't spinning:

Could be the solenoid. It's similar (but not the same) as used on a lot of older Fords. There's a disc contact that gets burned and can become intermittent. To test, put a test light on the starter cable and see if it lights when you get the 'click'. If no light, bad solenoid. If light, bad starter.

Also, starter could have a bad commutator and won't spin when it's in certain positions. You could try turning it manually next time it just 'clicks' and see if it cranks.

 

[jhouser]

That is interesting interalian, I will look at that as well. Thank you.

 

[oldboat1]

believe your starter is in line to be tested -- sounds like it's due for a rebuild.

 

[82rude]

I had a similar issue with a merc years ago and after doing all the usual stuff it still did the same nonsence the same as yours.In my case the cables to the battery were green as in rotted.check all your cables for rot .

 

[jhouser]

Ok I have an update, I think my solenoid is the problem, but I would like to get you guys' opinion to make sure I am on the right track, because I am new to troubleshooting motors.

First I checked the bendix to make sure it was not sticking or rusted. No problems that I could see, it looks clean, no rust and it moves freely. Next, I had a friend turn the key while I was by the motor, testing voltage with a voltage meter.

First I checked the battery to make sure I had juice, the battery had 13.2 volts. Then I checked to make sure the solenoid was getting proper voltage. It read at about 12.5 volts. Then I moved the test leads to the starter, it was at zero volts with the ignition off.

Then I had my friend turn the ignition all the way - the solenoid clicked like it likes to do, and I only got about 0.02 volts at the starter, it was barely anything. I did this test many different times, testing the leads to different places on the wires, and it was always the same, 0.01 or 0.02 volts with the key turned all the way. Does this mean my solenoid is bad?

Side questions:

1. I put the test leads on the two things on the front of the solenoid (the smaller bolts - what are they?) - they read 0.00 volts unless the ignition was being turned all the way on to the start position, then it was around 12 volts if it was held for a few seconds. They would start at 3 volts when the key was first held, then a second later the voltage would go up to 6 volts or so, then 9 volts then 12 volts after about 4 or 5 seconds. Is this normal?

2. I looked for several minutes, I could only find one wire going into the starter, which looked like it was coming out of the Solenoid, so I am assuming that this is positive, correct? Where is it grounded - is the ground one of the bolts that holds the starter in place?

 

[1983 ercoa 21']

The two little post one is ground the other is the 12 volt exciter from the key that activates the connection of the two big post that supplies the voltage and amperage to the starter.
clean all connections.
get a new solenoid and replace it 90% of the time that's the problem.

 

[jhouser]

Can I get one for a 1988 88 Johnson SPL at an auto parts store, or do I have to order it from Johnson?

 

[1983 ercoa 21']

Check and see. You will probably find something that will work but mounting might be different. Some parts stores have a marine line like Napa

 

[Scott Danforth]

before replacing parts make sure its not the connections. 90% of the time it is the connections

remove connection, clean with emery cloth or a wire brush until its shiny, re-bolt connections. then when done, hit with electrical varnish to prevent corrosion going forward.

 

[jhouser]

No Title

Ok I will clean all of the connections again, just to be sure that is the issue. They need to be cleaned anyway regardless of whether or not I get a new solenoid.

Is there a ground for the starter I am missing? Or is the ground for starter the motor chassis? I attached a picture of the starter. Where is the ground? I only see a positive input. Thanks.

 

[oldboat1]

starter mounting bolt grounds to powerhead. Needs to be common ground, keyswitch, solenoid, starter, powerhead, battery.

 

[bwkre]

Does the solenoid look something like this? If so , here is a trick to test. Have someone turn AND HOLD key to get your "click" sound. Tap the solenoid with the wooden butt of a hammer. 9 times out of 10 the contacts will make & your motor will spin.

But also be warned that this type of solenoid, when aged, also has a nasty habit of welding itself on and powering your starter regardless of key position. Always be prepared to remove the battery power.

 

[Fed]

Test across the battery Positive & Negative & turn the key to 'start'. What do you get?
Test across the large battery Positive on the solenoid and the engine block then turn the key to 'start'. What do you get?

 

[Fed]

I see you're now shopping for a new solenoid, I think you're wasting your time & money.

 

[Silvertip]

The quickest way to determine whether it is starter or solenoid is to use a jumper cable and simply jump the two LARGE terminals on the solenoid. If the starter spins every time those two terminals are connected, then the solenoid is the issue or the wiring that triggers it is the problem. that too is easy to check. Meter POS probe on the small solenoid terminal. Meter NEG probe on a good ground. Have a buddy turn key to START. if 12 volts present replace solenoid. If no voltage or significantly less than 12.6 troubleshoot the ignition switch circuit.

 

[Fed]

For the OP, notice Silvertip said 'terminals' to jump across on the solenoid, NOT lugs, NOT nuts... he said 'terminals'.

Silvertip I think he'd be better off measuring the Voltage directly across the 2 small terminals when the key was turned to start, then if there was not 12 Volts there ask the question.... why not? Connecting to a known good ground sort of defeats the reason for testing.

Notice the OP got some 'funny readings' when he tried that, possibly a dodgy main ground connection to the block when combined with the funny starter motor readings.

Someone should do a sticky on starter circuit testing, so simple but so frustrating to explain in full.