Unreliable cranking

duality · Dec 1, 2013

i am not familier with your engine setup, but as i recall on my hunter an issue was the starter button wiring. is yours direct wired to your starter button or is there a relay near your starter? you could be experiencing drop if you are sending the energy to the cockpit then back to the engine.

mike

stevec22206 · Dec 1, 2013

If the original wiring harness has not been upgraded you may be experiencing the poor start condition due to that. I've replaced the harness as well as the start and glow plug button on ours. Also inspected and cleaned the ground at the engine. There are several threads regarding the wiring harness upgrade, a quick search here will explain it all.

Steve

Maine Sail · Dec 1, 2013

John rolka said:
I have a Universal M18 in a Catalina 30, I have to hope every time I turn the key, sometimes it cranks, sometimes nothing. Last seasons solution to this was a spare battery on board that I would use to jump the installed engine battery.

I have 2 EGC golf cart batteries in series for the house and a 600 CCA group 24 dedicated to the engine. My initial thought was the batteries were bad, and was planning on a new set for next season.

Since hauling I've taken the batteries out of the boat, load tested them and done more research. From what I found given the condition of the batteries, they aren't that bad, the cranking battery holds 12.7V and the house 12.6V, by the load tester they are "good" I wouldn't expect to have been having the problems cranking I was. I need to maintain 9.something volts under max cranking load for the starter to turn. I'll check the voltage drop, I'll also check the wiring. My question is: is excessive voltage drop a symptom of a bad or deteriorating starter motor?

Thanks for your thoughts,
John Rolka

#1 The starter wiring on early Catalina's was quite undersized and leads to quite a bit of voltage drop during starting. Lots of voltage drop means a less aggressive starter. Today Catalina uses 1/0 and 2/0 wire for the same sized boats & starter loads.... Rx = new battery cables & terminals.

#2 Most builders ground to the engine block where ever it is convenient not where it is electrically best suited. Trying to pass hundreds of amps of current through rusty engine parts, dissimilar poor conducting metals, paint etc. etc. is just dumb. The best place for the negative cable on a marine engine is directly to a well cleaned mounting ear & bolt of the starter motor, not on the other end of the engine. Rx = move engine ground to the well cleaned starter ear and clean all terminals in the starter circuit.

#3 The solenoid wiring is also and can also be suspect on these early motors. Rx = replace terminals, clean all contacts, use larger gauge wire of 12GA as a bare minimum, and use a fuse sized for the wire in that circuit.

#4 Due to the voltage drop it may be that your solenoid contacts are burned and not performing as they should. Rx = have starter checked out and possibly re-built.

#5 The original wiring harness on those motors can be down right dangerous. They used two trailer type connectors that corrode and create voltage drop due to high resistance. Rx = Cut out the trailer connectors, strip back the wire and clean it very well, and use a t-strip & ring terminals or butt splices.

#6 Any group 24 or pair of 6V GC2 batteries will very, very easily start your motor. The problem is most likely in #1 - #5 above, if your batteries are in good shape...

Apex · Dec 1, 2013

My starter problem was due to a loose ground: An easy fix: tighten and enjoy. Of course Maine knows his stuff, so any suggestions are usually treated as religion. Maine do you ever get to simply enjoy the forums without electrical troubleshooting? :O)

Donnybrook · Dec 1, 2013

Find the red and yellow wire that goes to the starter solenoid. Look for the in line fuse. Take apart and clean it.

Tom J · Dec 1, 2013

An owner of a Catalina 30 at our yacht club had the same issue you do. He replaced the batteries and the starter, and still had the same issue with starting. Finally, he hired a technician who proceeded to change out the starter and battery cables. Problem solved. The tech is a guy I used to work with, and he said the cables installed on the old Catalinas were way undersized, just as Maine Sail says. So, obviously, if you follow all of Maine's suggestions, you'll be all set.

Stu Jackson · Dec 1, 2013

Further to Maine Sail's post, our C34 Critical Upgrades topic includes a lot of items you should know about.

http://c34.org/bbs/index.php/topic,5078.0.html

JohnShannon · Dec 1, 2013

Nothing?? So no clicking sound? no slow rrr rrr rrr? Utter quiet?

Other times starts as normal? In this case it is most likely the control wiring "key switch or starter button and the connections to it.

My boat does that, either it starts perfectly, or nothing at all happens, jiggling the wires on the back of the key switch usually gets it going.

Stu Jackson · Dec 1, 2013

John's right, but, please remember there are two basic things in that wiring: 1. The button, which most people blame for the problem
2. The fuse & the fuseholder in the wire between the switch and solenoid. That $1.83 [1936 price!!!) usually is culprit, not the button or switch. {Just 28 years of experience...}

Eddie7045 · Dec 2, 2013

Ignition key switches are a 20 year maintenance item.

20 years or as needed which ever comes first. The same thing happens to cars but most cars don't hang around that long so people rarely see that happen. Be sure when you replace the switch that the drain hole in the body of the switch is pointed downward.

Another item to be considered in an older boat is the battery cables. Some manufacturers use solid copper cables which are not marine grade meaning that they are not tin plated. Solid copper is good quality for an automobile but not enough for a marine environment.

Richard19068 · Dec 2, 2013

Check the attached service bulletin most of which is reiterated in the above comments.

Unreliable cranking

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