AGM and Flooded battery combination
I recently bought a boat that has a regular 12 v battery for the 90 hp outboard eng and a Optima 12 v AGM to run a few lights. I would like to put them in the same area and combine them for recharging...
Forum Discussion
A 90Hp outboard engine????
If it's a Yamaha Outboard I suggest you continue reading my warning if another brand - I can not speak from experience but suggest you ask that specific brands Marine Forum members - Outboard engines are VASTLY different from RV charging systems
If it's a Yamaha EFI engine - check what Yamaha says about AGM batteries
They are very specific that only flooded lead acid batteries be used as starting batteries
Clearly stated in their manuals
NO Sealed Lead Acid batteries
NO Maintenance free batteries aka sealed Lead acid
NO AGM Batteries are to be used as starting batteries
NO Wing Nuts are to be used at all for battery connections
The Rectifier/Regulator assembly is know to be a poor weak design and many times when it fails it takes along the ECM module - Both together run $250 or more for the parts alone
Be very careful
Use only a flooded lead acid battery as a starting battery
The AGM is a great Trolling motor battery and can be topped up from the outboard charging circuit with the appropriate connections
The Yamaha F90TLR charging voltage is typically a constant 14.8Vdc @ a max of 25amps - if you plan on using it to charge more than the single starting battery install a fuse to protect the Rectifier/regulator or plan on purchasing a new one within a year
I have three Yamaha Outboard EFI engines and Yes I have a F90TLR
Suggest you check out the many Yamaha Marine Forums
RV Charging circuits with high power engine alternators, Solar systems, converters or inverter/chargers are vastly different from outboard engine charging circuits
If it's a Yamaha Outboard I suggest you continue reading my warning if another brand - I can not speak from experience but suggest you ask that specific brands Marine Forum members - Outboard engines are VASTLY different from RV charging systems
If it's a Yamaha EFI engine - check what Yamaha says about AGM batteries
They are very specific that only flooded lead acid batteries be used as starting batteries
Clearly stated in their manuals
NO Sealed Lead Acid batteries
NO Maintenance free batteries aka sealed Lead acid
NO AGM Batteries are to be used as starting batteries
NO Wing Nuts are to be used at all for battery connections
The Rectifier/Regulator assembly is know to be a poor weak design and many times when it fails it takes along the ECM module - Both together run $250 or more for the parts alone
Be very careful
Use only a flooded lead acid battery as a starting battery
The AGM is a great Trolling motor battery and can be topped up from the outboard charging circuit with the appropriate connections
The Yamaha F90TLR charging voltage is typically a constant 14.8Vdc @ a max of 25amps - if you plan on using it to charge more than the single starting battery install a fuse to protect the Rectifier/regulator or plan on purchasing a new one within a year
I have three Yamaha Outboard EFI engines and Yes I have a F90TLR
Suggest you check out the many Yamaha Marine Forums
RV Charging circuits with high power engine alternators, Solar systems, converters or inverter/chargers are vastly different from outboard engine charging circuits
