1979 Johnson - battery charge and load question on 70EL79

[opc167]

I?m restoring and upgrading our families 1979 Saber 17? with a remarkable 70 Johnson that has been maintained 110% over its lifetime. I want to first add an instrument cluster for Temp, RPM and speed gauge so I can monitor settings while balancing the boat and set the appropriate trim settings and prop replacement. This boat was a fishing boat but we are converting its use for Coast Guard Auxiliary use. My question is in regard to using twin batteries. We are using two deep wells near back of boat. Each one will have a fuel tank and battery. We will run the two batteries in series to keep the 12 volts. Will this cause any restrictions in ?Charging? from the 70EL79 model? Our approach to this method is creating a perfect balance in fuel and battery weight on both sides. Any suggestions or concerns, I would greatly appreciate it. Also, this particular model does have the overheat alarm in the controls that I will bypass.

Best regards.

 

[Crosbyman]

Re: 1979 Johnson - battery charge and load question on 70EL79

We will run the two batteries in series to keep the 12 volts. ???

that is 24 volts !!!!!!

better wire the batteries in parallel or something will burn up

or were you talking about 2x6 volts batteries in series

 

[boobie]

Re: 1979 Johnson - battery charge and load question on 70EL79

I would recommend installing a battery switch. That way you can run on bat # 1, bat # 2, or both. And shut all bats off when not in use.

 

[phillnjack2]

Re: 1979 Johnson - battery charge and load question on 70EL79

I think its pretty obvious he means is postitive to positive and negative to negative, that way he keeps 12 volts and
just doubles the amp capacity.

Different countries have different meanings, some say in series meaning positive to positive and some say parralel meaning the same..

I would do like boobie says and put a 4 way switch on...batt 1, batt 2, batts 1+2, and off.

also make sure they are well vented if keeping near the fuel tanks each side !!!!!!!!!!


phill

 

[opc167]

Re: 1979 Johnson - battery charge and load question on 70EL79

Thanks. Correction noted. I did mean to state in parallel.

The deep wells are partitioned now. One side tank, the other side battery. I'll try and find out what the charging output is from the motor. The 4 way switch is what we will go with.

thank you for the feedback.

 

[emdsapmgr]

Re: 1979 Johnson - battery charge and load question on 70EL79

Many of these early engines did not have power trim. As such, they had anemic charging systems-maybe only 6-8 amps. The A/B switch would be ideal for your application and the dual batteries are a good idea. I would not expect this engine to provide much charging in your application. Esp if you are running special gps, instrument and radio systems. You may want to add an on-boat battery charging system to make sure your batteries are fully charges before each trip out.