Troubleshooting starter problem

[rjabara]

I saw this same issue posted many times, and have read most/all and have TRIED to understand steps that I can take.  I am hoping someone can help with a few diagnostic tips that can get me to an answer.

1.  After a few hours of sailing (and motoring), and a stop for lunch, with electronics on and radio on.  Pushed start button to leave and nothing, no crank, just silence.  For the past 18 months since I have had the boat, the engine always started immediately first try.  I waiting a few minutes and pushed the button again and it started right up.

2.  A week later, engine started right up at the slip, but when restarting after sailing a few hours nothing.  Waited a few minutes, tried again and started right up.

3.  Today, went to try to figure it out.  Unplugged, turned on radio and electronics and let it sit for 3 hours.  Pushed button, nothing (radio and alarm and electronics still working fine)  Pushed again, started right up and started up 5 times in a row after.
I let it sit for another 2 hours, then I could not start it at all.  Tried 10 times and silence each time.
Plugged shore power in and let battery charge for an hour or so, started right up and repeated 5 times with no hesitation.

I have checked the grounding wire and it is solid.  I checked the battery cables and all looks tight (pic attached).  I looked at all of the connections to the starter/solenoid and everything looks tight with no corrosion.

My initial finding are:
 I don't think it is the start button, as when plugged into shore power it fires perfectly and multiple times.
 I don't think dead batteries, as the radio/electronics keep playing throughout(?)
 Maybe a power loss between the battery and the starter switch when the battery is being drawn down but not dead? 

Any thoughts appreciated before I start start sticking screwdrivers in.  Thanks in advance.

[KWKloeber]

@rjabara

There is no magic bullet, single-cause, answer here but there are two truisms that apply.

Either (1) the starter solenoid is faulty (doesn't consistently activate the magnetic switch) OR (2) the voltage to the solenoid is low and it cannot activate (pull in) the magnetic switch.

#2 is more likely than #1 and is easier to troubleshoot.
When you cannot activate the starter, the idea is to troubleshoot AT THE solenoid to determine if it has low voltage.  if the voltage is low, then find the cause, which can be a handful of causes. 

The start switch could indeed be the problem (burned contacts) and has enough V loss so the solenoid pulls in only when the Batts are being charged (14+ V.)

When trying to start (non-start condition) check voltages EVERYWHERE, from the battery to the key switch, to the start switch, to the solenoid.  That will help I.D. where the "bottleneck" is occurring. It can also be cumulative, being corroded cable lugs from the battery through the selector switch to the panel, the solenoid. Add up all the V losses and you have a large V loss.

The wiring on the B engines is very different than the Oshkosh Universal M-35 so print out the proper wiring schematic from the Wiki Site MANUALS page and use it to record the V at your key locations. MAKE sure all negative cable connections are clean and tight, as as well as the "S" wire terminals (which energizes the solenoid switch.)

Another approach when you have a no-start, is to bypass the panel and START button and apply a good, known 12v directly to the starter solenoid.

The other check is to hear whether the solenoid switch is indeed pulling-in, but the starter motor is not activating.  That's a way different issue and likely needs to have the starter pulled and checked out at a shop.  The starter motor not energizing can too, be caused by low V at the battery cable terminal.

Also, it looks like some battery terminals need attention.  The cables with the highest load go on any terminal post first and progressively lighter-load wires on top.  It sure looks like you have lighter terminals underneath some cable lugs.

Let us know the V readings that you see!

[Stu Jackson]

...and nothing, no crank, just silence. 

On our M25 engines there was/is an inline fuse between the start button in the cockpit panel and the engine.  Details in the Critical Upgrades sticky topic.

[KWKloeber]

an inline fuse between the start button in the cockpit panel and the engine. 

Note that the pesky fuse is not present on the (OEM-wired) A and B series engines.  The "S" wire is direct to the solenoid. 

The panel, etc. is protected by a PB Circuit Breaker on the engine, below the cube Fuel Pump, plus the panel PB Breaker.

[Jon W]

If the ProSport 20 in your photo is your AC charger, you should consider upgrading to a better quality AC charger.

[Indian Falls]

Here's some advice:  don't just buy a new starter to solve this.  Have someone replace the starter solenoid if that's it.  I wouldn't rule out your start button either. I know how intermittent they can get.

A friends C30 sunk at the dock.  He had his alternator opened and cleaned up but he replaced the starter.
That thing would not start the engine.  It acted like low battery or bad connections.  Every revolution the crank would almost stop at the top of each cylinder compression.  I put the sunken not repaired starter on and put the new one back in it's box.  Started right up. The diesel shop he bought this from swore up and down it was the same starter.  To rule out the starter button just jump the main terminal on your starter to the solenoid connection (blade term, yellow wire) with a screw driver. IF your solenoid misses the starter will spin but not the motor. If you get nothing this way, the internal connection to that blade connector on the inside will need looked at.  In event it misses often, spins but doesn't engage the engine maybe some grease on the throw out would fix it.  Hope this helps. 

[waughoo]

I recently had my statter rebuilt at an electric motor shop.  It was getting to be intermittant (not the switch or connections) so I elected to rebuild it before I got stuck somewhere.

[rjabara]

Great info, thank you very much.  I will check all the voltages and report back.

In the meantime, re: "Another approach when you have a no-start, is to bypass the panel and START button and apply a good, known 12v directly to the starter solenoid."  How do I do this?

Thank you.

[Ron Hill]

Rich : I don't know which battery/s you have connected when you are starting?  I have my battery selector in ALL and the starter battery engaged.  I use as many Volts/Amps that I can muster when starting!!

You can always pull the engine panel and jumper the contacts on the starter button to see if it's OK!!

A few thoughts

[rjabara]

Ron, I have it set to 1+2 when starting, but tried all versions (1,2,1+2) and all failed to crank.  When on shore power, also tried all versions and all fired right up after it charged for a while.

I was hoping to avoid opening the panel  as my project list is long enough.  Ignorance is bliss (until it's not)

[KWKloeber]

bypass the panel and START button and apply a good, known 12v directly to the starter solenoid." 

How do I do this?

Have you downloaded the parts and service manuals and wiring schematic for your 35B engine?

To bypass the start switch you would put 12v directly on the "S" Terminal at the starter.  The wiring schematic will help you -- just follow the wiring from the Start PB Switch to the starter and eliminate the possibility of the Start switch or the "S" wire being bad.

You can also get fancy and make up a PB Remote start switch with a terminal to match the starter "S" terminal and an alligator clip or ring terminal to pull a good 12v supply. 

-ken

Note that some of the prior messages talk about a different starter on the (Oshkosh) Universal engines, and although all starters "start", the starter on the (Westerbeke) B engines (25XPB, 35B, etc.) are somewhat different.  Unfortunately, I do not have a good photo of those starters.

[rjabara]

Ken, here is what I am using, not sure if you can read it as it is very small.  Can you identify where I should put the 12V?  Is it where the yellow-red wire connects to the starter?

[KWKloeber]

That is not even close to the OEM wiring on the B engines.

The concept is simple, apply 12v to the "S" terminal on the starter.
I said, the schematic and manuals for the M35B are on the Wiki Site.
https://c34.org/wiki/index.php?title=Manuals

If you are sketchy about following wiring schematics and locating the starter "S" terminal, you need "hands-on guidance." 
Being unsure of what's what, you probably need to get a qualified assistant to help troubleshoot this.

You have about enough energy stored in your battery bank to get hurt or weld something to your starter case if you happen to short out the wrong thing. 

[Stu Jackson]

Ken is right. That diagram has an ammeter, which your Mark 1-1/2 boat certainly does NOT have.

[ghebbns]

I was one of the people having very similar issues to you.  One thing I noticed is that on the times that I pressed the starter button and nothing happened, there were no changes to the gauges.  Normally when it starts, the gauges all move to the left while holding the start button.  This acted more like I wasn't even pressing the button.

I replaced the starter button ($30 fix) and have not had the issue again - although I admit that I am not 100% sure it is cured.