55EL78S a few questions please

[OLDIRON]

I Just got it running with muffs at a high idle and not too high of water pressure.So here's my questions.
1) Fuel mix. I'm pretty sure it's 50:1, just want to make sure.

2) Will this motor run without being hooked to the battery? I know it won't start.Dah. Thought about disconnecting the battery while it was running, but I don't know if that would cause some weird spike in the electronics. I just put a new CD pack in it and I don't want to fry it being stupid.

3) I do have water out the tattle tail but it seems to be intermitant, sometimes a steady stream, sometimes not. Does the thermostat control its out put, or should there always be a good steady stream. I am going to do a pump service anyway. Which leads me to my next question.

4) How hard is it to do a water pump change? Just the impeller? Or do I need to do some kind of housing change. I've changed lots of impellers in the past, but not on this big of motor.What I'm I looking for here when I get it apart?

5) How much voltage should the alternator be putting out? My battery is fully charged. But when it was at idle, and I didn't really rev it too high, the meter still read about 12 volts. Shouldn't it be putting out about 13-14 volts? Or does it have a built in regulator that stops the output when the battery is fully charged?

Well, that's it for now. please feel free to answer any, if not all of my questions.

 

[jonesg]

Re: 55EL78S a few questions please

I Just got it running with muffs at a high idle and not too high of water pressure.So here's my questions.
1) Fuel mix. I'm pretty sure it's 50:1, just want to make sure.

2) Will this motor run without being hooked to the battery? I know it won't start.Dah. Thought about disconnecting the battery while it was running, but I don't know if that would cause some weird spike in the electronics. I just put a new CD pack in it and I don't want to fry it being stupid.

3) I do have water out the tattle tail but it seems to be intermitant, sometimes a steady stream, sometimes not. Does the thermostat control its out put, or should there always be a good steady stream. I am going to do a pump service anyway. Which leads me to my next question.

4) How hard is it to do a water pump change? Just the impeller? Or do I need to do some kind of housing change. I've changed lots of impellers in the past, but not on this big of motor.What I'm I looking for here when I get it apart?

5) How much voltage should the alternator be putting out? My battery is fully charged. But when it was at idle, and I didn't really rev it too high, the meter still read about 12 volts. Shouldn't it be putting out about 13-14 volts? Or does it have a built in regulator that stops the output when the battery is fully charged?

Well, that's it for now. please feel free to answer any, if not all of my questions.

50:1
Being that old 1978, I'd change everything in the water pump.
If you disconnect the battery running you will fry the CD pack.
As long as the battery reading isn't lower than 12v I wouldn't worry too much, you're not losing battery power at idle.
Water pump is simple, like everything else IF you buy the service manual.
www.outboardbooks.com

 

[OLDIRON]

Re: 55EL78S a few questions please

50:1
Being that old 1978, I'd change everything in the water pump.
If you disconnect the battery running you will fry the CD pack.
As long as the battery reading isn't lower than 12v I wouldn't worry too much, you're not losing battery power at idle.
Water pump is simple, like everything else IF you buy the service manual.
www.outboardbooks.com

Thanks for your input on this.I almost disconnected the battery and then I thought WHOO! Good thing I didn't. So your saying this motor will not even start with a emergency pull rope if the battery is dead or disconnected? Is that correct? Or just that you can't disconnect it while running. I would think the whole point would be that you could still start and run the motor even if your battey was dead. Or if one of the battery terminals opened up by accident.

 

[EN2]

Re: 55EL78S a few questions please

You can rope start it, ignition is powered by magneto cd.

 

[OLDIRON]

Re: 55EL78S a few questions please

Thanks EN2. I would think that the battery would only be needed for starting with the key.

 

[OLDIRON]

Re: 55EL78S a few questions please

Just thought of one more question. This motor has a temp sensor in the cyl. cover.What does it do? Does it shut the motor down when it gets too hot? Or does it turn on a light at the dash, which I don't have. There are some taped off wires coming out of the command center but I though they were only for the tach and tach light, which I also don't have.

 

[ezeke]

Re: 55EL78S a few questions please

The temperature switch in the cylinder head (tan wire) is just a switch that goes to ground when the engine overheats. When grounded, the horn in your control should sound.

Test the circuit by grounding the control end of the tan wire with the ignition on - the horn should sound.

 

[OLDIRON]

Re: 55EL78S a few questions please

The temperature switch in the cylinder head (tan wire) is just a switch that goes to ground when the engine overheats. When grounded, the horn in your control should sound.

Test the circuit by grounding the control end of the tan wire with the ignition on - the horn should sound.

Thanks ezeke. I'll check that today. Well, that's one more mystery solved about this motor. This is the newest, and largest outboard I have ever owned so right now it's alttle intemidating.

 

[OLDIRON]

Re: 55EL78S a few questions please

The temperature switch in the cylinder head (tan wire) is just a switch that goes to ground when the engine overheats. When grounded, the horn in your control should sound.

Test the circuit by grounding the control end of the tan wire with the ignition on - the horn should sound.

I tested it the way you said, and yes,the buzzer did sound off in the command center.Thank you so much.I love this forum! Maybe someday I can help someone out like you guys have done for me.Thanks again.