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Battery for 78 Johnson

D

dofunny

Member
78 Johnson
Model:70EL78C

78 Johnson
Model:70EL78C

Hello Fellows
What size battery should I buy for the 78 Johnson motor?Should I buy the battery everyone is telling me about at Wal-Mart? How many volts should this battery have? But at 12.7 volts the engine will drags and will not start at this point until I get 13.4 and above volts in the battery. Can anyone help me out there.
 
"A normal 12 volt battery in t

"A normal 12 volt battery in the range of 70 amp hours would be fine.

If the new fully charged battery will not crank the engine properly, the fault would lie with loose or tight but dirty cable connections or a failing starter.

Remove, clean thoroughly, and tighten all connections with a wrench or pliers (not your fingers if wing nuts). This includes the battery post terminals, and the starter solenoid, etc.

If the starter get very hot, that's usually a indication that it requires reworking or replacing. A hot cable usually indicates a loose connection nearby OR a cable that is failing internally due to corrosion etc."
 
i fully agree with Joe and wou

i fully agree with Joe and would like to add a comment...some battery cables cables will get stiffer than normal for an inch or two at the connection point...this is what is called chrystalizing..you can actually see the corrosion beween strands if you take a knife and peel back the insulation..this will add resistance to the wire and cause a voltage drop going to the load(in this case the starter)..you can measure this drop only when you are actually pulling current...to measure place meter across battery and try to start..measure voltage...then move positive meter lead to the starter positive post and try again..the voltage should be the same..if less voltage than across battery then you have a voltage drop somewhere..dont overlook the fact that the ground side can have a high resistance also..to test for this just reverse procedure..leave positive lead on battery and go to starter ground...
 
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