" For suppression and to take out surge ripple.... They work great in cars for this purpose... "
Reminds me of the old joke about a man walking down Park Avenue in NYC
always snapping his fingers. One day someone asks him why he's always doing that, and he says "It keeps away the lions" and the man says "But there are no lions in NYC" and he says "You see? IT WORKS!"
Uh, no, massive electrolytics are not used that way in cars, not by the folks who make the cars. Some car audio freaks use them to supply transient power surges for bass response and a few other real issues, but in general? There's no ripple coming out of your alternator
unless it is defective. There's no surge unless it is defective. The cap can filter out spikes but there are smaller cheaper spike protection devices that you can get and use.
Yes, capacitors can filter out some things. I used two single-farad caps as filters in a big old analog power supply, and they work beautifully, Which leads to what Skip said: How long they last is a quality control issue. Cheap
ones may leak and die in five years, good ones show no problems at 40 years.
Horses for courses and huge electrolytic caps are just the wrong ones for boat electrical panels
. Fix your alternator
, use spike protection devices where and as needed, save the big cans for something else. Like a car with too much sound system.