The old bosch has taken too much abuse over the years and doesn’t hold it’s charge that long even after conditioning on the CTEK charger.
Pulled the battery out, gave this area a bit of clean. Ther rubber disks are actully old bump stops with the tabs cut off. Gives a sold yet slighly squishy place for the battery to rest against.
New battery is an Optima Yellow Top R 3,7 D35 deep cycle. It’s a little bit smaller than the old battery. CCA is 660. The terminals clear the battery which makes it much easier to put charge clamps on them.
Not forgettinh to change the charger setting to ‘AGM’ if you don’t there’s a risk of overcharging – which will end up venting water vapour that you can’t put back in.
Cold start and luke warm start:
https://www.youtube.com/watch?v=TVv0Jr880JE