intermittant starting problem

[Rick R.]

Whew!

This one was exciting.

Bravo to Herb for articulating what was happening. Often with electrical problems the hardest part is explaining the issue. Add in a multi-position battery switch, reconfigured wiring from the boats PO and you have a recipe for confusion.

 

[HerbertFriedman]

I will talk to Blue SEas but I did buy that switch on line not at my local chandelary so getting compensation may be difficult. Lesson learned about saving dollars by dealing on line. Plus, I tried many times to document the switch problem once I got the switch in my hand with a ohm meter, but 10 out of 10 showed a short when I put the switch in the ON position, But then again, that continuity test is a "no load" situation. To really test the switch you should hook a 12 V source to it, and a load to draw some reasonable amount of current, say a few amps and then try the switch again, but that setup is a pain to do. Same thing about testing a battery, a simple voltage test under no load conditions rarely shows conditions such as a faulty cell, you need to draw current for that test. sigh.

Still not convinced it is the switch, the problem really does sound like a faulty ground. I will try starting the engine several times over the next few days before I put humpty dumpty back together again, it is a real pain to get at that switch. I have to remove one battery with all those heavy cables, and open an access port and again heavy cables, lots of cuts and bruises but hey, its a boat. If you dont hear from me, problem solved.

 

[Tom Metzger]

Herbert - The problem has always looked like a bad connection. The only connections it can be are in the line from the engine ground through the battery to the switch. I think you claimed to have cleaned/remade/tightened all of those connections. The bad switch is very believable.

You might be able to take the old switch apart which could make the problem apparent.

 

[HerbertFriedman]

Final report....somewhat embarrassed. Installed new switch, put humpty dumpty back together, tested starting several times, all OK, looks like the switch was the problem after all, ....well maybe. Before closing up the access ports, might as well check the battery water, house bank looked OK, topped off with a ounce or so of distilled water. Getting at the starting battery more difficult but managed to pry off cover, water level looked same but when I was putting the cover near the + terminal, noticed that the heavy battery cable was LOOSE!.

First thing I did when started this "witch hunt" was to check all the nuts on the battery connections, all tight, then I wiggled all the cables, none loose, OK , on to the next step and you all know the rest of the story. Turns out the loose cable was below another smaller cable which was a Blue Seas fuse terminal strip with two ceramic fuses, one to the battery charger, the other to the Automatic Charging Relay (go to Blue Seas to see these components).

The connector of the heavy battery cable was nicely rounded so that the angle made little difference but the Blue Seas terminal was squared off and due to the very limited space available, only one angle was possible. The square corners of that terminal was wedged against the battery post and therefore tight. Plus it appears that the $0.17 nut was "buggered". That is why the nut was tight even though the nut was not screwed all the way down on the battery stud. So the nut was tight and the top cable, the fuse terminal strip was tight but the battery cable below it was making some contact but certainly not tight.

I verified that the threads on the nut were bad (even though visually it looked OK) and the threads on the stud were OK by switching nuts back on forth on other studs. A quick trip to the local chandlery, installed new nut, tested starting, all OK (but then all was OK before I changed the nut), but a loose cable with an intermittent connection would act the same way.

Sooooo, my gut feeling is that I am $50 poorer but much wiser, you all were probably right. All for a $0.17 nut.... and some sloppy workmanship on my part. Thanks again to you all, great site

 

[October]

When the ignition is on, a hot wire goes to the glow plug button then....from that same post that goes to the starter button that is the way Ericson did it. Now go from the ign. switch directly to the starter button and eliminate the wire that goes from the glow plug button to the starter button....this way both buttons receive power directly from the source. if you use a jumper from the ignition to the starter direct...this should confirm a positives start. I had the problem on a new 1988 200....not sure why the original did not work. power is coming from the same source. Please respond and I will do what I can to help. I would be happy to give you my phone number. I am in the San Diego area.

Tried to start my Universal M25xp yesterday. I have three new batteries, 2 grp 27 for house and 1 grp24 starting. Turned on key, got usual oil light and buzzer indication, pushed glow plug and the electrical power dumped. Oil light and buzzer went out, no action from starter button. I cycled the battery switch from ON to OFF and then back to ON, turned key on, oil light and buzzer came back on, but again power dumped when I pushed glow switch. Finally switched battery switch to "all" combining house and starting batteries, and engine started in normal way. Back at the dock, checked all batteries for normal voltage so I dont think starting battery was low. Started engine in normal way (starting battery alone) several times, no problem.

I am about to order new glow plug switch and new glow plugs and I will make the wiring upgrade to disconnect start and glow switches but anybody have similar problems, suggestions, etc.

 

[HerbertFriedman]

My starting problem was finally solved when I found a loose cable on the +12 V terminal on the starting battery. The problem was a "buggered" $0.17 nut so that the nut tightened but did not press down on the cable fully, causing an intermittent contact. Spent $50 on a new battery switch before I found this problem.

However, I did confirm once I got the intermittent problem solved that the starter button works independently of the glo plug button. The starter button appears to be not original and actually has two leads both encased in plastic so that the terminals on the starter switch are not exposed. The wiring in the back of the panel is not easy follow but it looks like both the starter switch and the glo plug switches have a lead going back to the 12V terminal on the starter switch so that both switches are independent of each other. Problem appears to be solved, many thanks for your help.