Starting port side kills starboard...

[dixontim]

So I have a very weird problem. I have been trying to isolate the problem all summer so far with no luck.

I have a 1979 33' Carver Voyager with two 350s. One engine was replaced last year and both engines received new electric mallory distributors.

I am usually able to start both engines from a cold state with no problem. They warm up fine and idle fine. When I go to put the boat in gear, the port side engine has been cutting out. After it cuts out and I go to restart the port engine, the starboard side engine will cut out while turning the ignition. Sometimes neither engine will start after this but usually I can get the starboard to start back up.

I don't believe the problem is fuel related, as both engines are currently pulling fuel from separate tanks.

As far as troubleshooting the electrical side of things, I had a buddy test the ignition switchings and he feels relatively certain that is not the issue. I am not sure the exact process he used to determine this.

I am going up to work on the boat again this weekend (6/20/2008) and what I am looking for is as many good recommendations of things to check as possible. Any input would be greatly appreciated.

My tentative goal is to bypass the main battery switch and try to hook each battery (there are two relatively new batteries with full charge) to separate engines and see if the boat will run fine. I have had a few people suggest I check the 1/2/both/off switch.

Thanks in advance!!!!

Tim

 

[Bondo]

Re: Starting port side kills starboard...

Ayuh,...... Hi Tim,... Welcome Aboard.....

I don't know how your Bud did his Tests,...
But it sounds like you're loosing power to the Igntion,....
Hot Wiring the (+) side of the coil, will prove, or disprove it....

Are these motors turning Inboards, or I/Os,..??

 

[dixontim]

Re: Starting port side kills starboard...

Bond-O,

Thanks for the response! The engines are powering inboards through v-drives.

I guess I had a misspelling and wasn't super clear with what my friend tested. He tested the ignition switches themselves, but nothing with the coil, etc.

I'm pretty new to working with the ignition system and such. If you could let me know the approximate procedure to hotwire the positive side of the coil I would greatly appreciate it.

Thanks!!!

 

[Bondo]

Re: Starting port side kills starboard...

If you could let me know the approximate procedure to hotwire the positive side of the coil

Ayuh,.. Sure....

Run a Jumper Wire from a Known source of 12V power(such as the Battery) to the (+) side of the Coil......

 

[rodbolt]

Re: Starting port side kills starboard...

sounds like your fighting 2 issues.
one is a problem with the port engine, the other is your electrical system seems to be tied to both engines.
sometimes when that happens the current draw and attendant voltage drop on the system can take so much that the running engine drops enough voltage that the ign system cant function so it dies.
we see it a lot on older hulls with twins.
usually someone somewhere along the line left off a ground wire or misswired the battery switch.
you would not belive some of the wiring nightmares I have encountered on older hulls.

 

[chiefalen]

Re: Starting port side kills starboard...

listen when u run that wire from the battery to the positive side of the coil make sure u put a switch on it u cant leave power going to the coil only when the boat is running.u can melt the points closed.i happened to have wired a wire to my coil with a switch at the helm cause i couldn't never find y i had week power and i didn't want to put in a new harness.when u go to start the boat flip the switch.when u go to turn off the motor turn the key switch boat will still run than flip the switch to the coil works for me.i marked the switch with red label.u can run the wire from the positive side of the starter save some wire just make sure u have good power at the starter.clean them connections.good luck keep us posted

 

[JustJason]

Re: Starting port side kills starboard...

How many batteries do you have?

In my humble opinion you should treat the engines as seperate, and they should not be wired together in any way shape or form. Of course that's just my opinion.

 

[paulrfrancisco]

Re: Starting port side kills starboard...

u cant leave power going to the coil only when the boat is running.u can melt the points closed.i happened to have wired a wire to my coil with a switch at the helm

I thought that it was a no-no to even run a motor with a full 12v to the coil. (short tests are OK) That is the reason they used to put in Ballast resisters in cars and MerCuriser had the resister wire from the alternater to cut voltage to around 7-8v. Continously running a coil at 12 volts will burn out the coil and certainly shorten the life of the points... as I remember it anyways...

 

[chiefalen]

Re: Starting port side kills starboard...

the coil only gives out juice when the points are closed.if the points were closed the oil in the coil would also get to hot and the points would melt.i got this set up 4 years.when u turn the ignition key u momentarly supply power to the starter at the excate same moment giving power to the coil.u let go of the key it moves left and still the coil has steady power.as long as the motor is running the coil gets steady power.no the problem arises that the wire in some way get compromised for any reason there might not be enough power thru the same wire to power the coil and the starter hence the reason to run a wire from the battery or starter positive terminal.its cheap easy a fresh wire and it works.don't forget the switch.

 

[chiefalen]

Re: Starting port side kills starboard...

i agree with captjason no way should the 2 motors be wired together in any way.its ok to take fuel from the same tank but thats it.2 different electrical cut offs also.

 

[gdombroski]

Re: Starting port side kills starboard...

both engines received new electric mallory distributors

Check you spec on these or put a voltage meter on the coil. I would bet that they are wired to run at 12V from the coil as most aftermarket electronic ignitions, Pertronix, etc, are. If so, you should not have any problem with the 12V direct to the coil as there are not points to burn out. Coils are made to run at 12V whereas points need resistance to about 7-8V so they don't burn out.

When I go to put the boat in gear, the port side engine has been cutting out. After it cuts out and I go to restart the port engine, the starboard side engine will cut out while turning the ignition. Sometimes neither engine will start after this but usually I can get the starboard to start back up

Starboard cutting out when shifting is one problem probably not related to either ignition or coil. But, after stall do the engines turn over normally and not start? If they seem to be turning over slower I had the same problem, starting starboard would stall port,and couldn't figure out for a while as my starting battery was reading at proper voltage. Eventually got to where neither would turn over properly and start. So, took battery to be tested and it was reading at less then 1/3 its rated cranking amps. Replaced it and problem gone. Hope yours is that simple.

 

[Bondo]

Re: Starting port side kills starboard...

.no the problem arises that the wire in some way get compromised for any reason there might not be enough power thru the same wire to power the coil and the starter hence the reason to run a wire from the battery or starter positive terminal.its cheap easy a fresh wire and it works.don't forget the switch.

Ayuh,......With Advise like That,........ I'm Worried..........

Hot Wiring is a Diagnostic Tool,.......
Not how to run a boat, day in,+ day out.......

 

[Coors]

Re: Starting port side kills starboard...

Yeah; chief, you need to fix the wiring.

 

[bjcsc]

Re: Starting port side kills starboard...

Maybe you're only supposed to be using one engine at a time...

 

[chiefalen]

Re: Starting port side kills starboard...

you guys are probably too young to remember the real old time cars where there was no key to start a car u had a push button momentary switch for the starter and a switch for the coil.old old boats had that setup to.with saltwater eating wires on boats 20-30-40 years old they get green compromised.they get cut .what to do.these old wires just not allowing juice or enough juice to perform the proper function they performed when new.so u isolate the wire off the harness what next replace the wire.or splice the wire into a old harness that u know is already bad.splicing the very worst in my humble opinion to do. someone who uses there boat in saltwater will get stuck on the water.maybe not today but down the road.u on the water sun blazing kids crying and wife shooting u the fish eye.go figure out what wire u spliced and find it and fix it.my way is better,cheaper,a permanent fix that will last another 20 years.u need a good supply of power to the coil or u ain't going nowhere no how.oh don't forget the switch.good luck

 

[Bondo]

Re: Starting port side kills starboard...

Ayuh,....

And Hot Wiring the Igntion to the battery causes Burnt Points.....

That's why We Fix boats,+ Not just Hot Wire **** together....

Btw,... I'm plenty Old enough to know what you're talking about....
It was the Wrong thing to do Then, as it's the Wrong thing to do Now....

 

[rodbolt]

Re: Starting port side kills starboard...

wow, I must be getting old.
not only do I remember pull chokes I also remember not only a seperate starter switch on the floorboard but the old GMC I learned to drive on had a switch under the accelerator, simply mash it all the way down and the starter engaged.
however getting back to the 12 to the coil thing.
thats what the R terminal wire from the starter solinoid.
99% of inboard and sterndrive engines tap a seperate wire from the R teriminal to the coil +primary to insure full voltage when cranking.
cars with points did the same thing.
points normally run with 7-9 volts, its all the system needs once running, however at cranking the avalible voltage can drop to low due to starter load, thats the reason for the R terminal on the start solinoid.
but ya gotta remember, I am old enough to have worked on Packard Clippers,Ramblers, and I drove a Studebaker lark III 4dr in high school. 112HP,3 on the tree with O/D and the hill holder clutch. how many folks here can remember the hill holder clutch

 

[chiefalen]

Re: Starting port side kills starboard...

my first car had no fuel pump.when going up a large hill i had to back up the hill.back to the problem at hand.could be the main connector has a bad connection.in this age boat may be required to cut the connector off and hard wire or splice the wires together.that is after finding the wire that is bad.in my humble opinion if that route is taken than solder the connection and plastick shrink wrap the splice.there is always options whatever your most comfortable doing.i like doing it once.find the problem and fix it long term.the gentelmen in the original post wanted instructions on how to hotwire the coil.thats what he wanted.thats what i gave him.just don't forget the switch.