Logo
FULL SITE MENU

Recommended battery sizing for outboards

R

roger

Member
" I have a 1975 Johnson 115 V4

" I have a 1975 Johnson 115 V4. WIth a full charge on the batteries one cranks slow and won't start. On the other battery it cranks faster and starts, but seems like its struggling. What are the recommended battery sizes for such a motor? "
 
" Roger.... The ignition on yo

" Roger.... The ignition on your engine is self contained (needs no outside power source) and is called a "Magneto Capacitance Discharge" system. It has to to develop 300 rpms in order to create the spark. Faulty batteries or loose connections, bad cables etc result in low rpms and no spark, hence the engine can not start.

A general rule of thumb, and a recommendation of OMC is that a marine battery should be at least a 70 amp hour battery.

Joe (30+ Years With OMC) "
 
" Yes, on the 70 AH rating, bu

" Yes, on the 70 AH rating, but I was most looking for A CCA rating. Just as with cars larger engines require higher CCA to spin them up to speed. Is there a comparison for Marine instances? "
 
You must log in or register to reply here.
Back
Top