FL-356C

I have my C at the shop getting her serviced after a lonnnng winters nap. The 6 volt battery seemed very low, but tested ok and charges fine. But, very slow to turn over and will not start the car. My mechanic is suggesting going with an 8 volt, and says that it is a good compromise if I am not redy to switch to a 12 volt system. He said that nothing needs to be changed over with an 8 volt. I just wanted to see if anyone has heard of, or done this?

luvmy356

why not just run a 6v Optima? My Roadster sometimes hibernates for months at a time and there is always plenty of juice to crank the motor and refill the Zeniths before the motor starts. And my Optima is almost 10 years old.

FL-356C

Are the Optimas that much better/powerful? I hear about them alot in the offroad world, but never looked into them. Might be a good option.....

ked

recently, there was a series of posts on 356 Registry Talk on this topic. I'd check into that resource. as I recall, the upshot was don't do it... it is a dangerous band-aid over possibly serious issues. either make your 6V system work as it was designed, or convert to 12V.

in your situation, I'd jump-start the car & see how the old batt behaves, consider installing a fresh one, perform an elect system tune / refurb (charging / starting sys, batt cables, relays, etc)... on this & related 356 elect matters, Joe Leoni is "the man".

FL-356C

Thanks Ked. I just found that article as well. It looks like luvmy's Optima + a good system clean is the way to go.

Mike Murphy

My 1949 Chevy pickup truck ran much better when I converted to 12V from 6V. I did not have to replace the starter, interior light bulbs and many other components when changing to 12V. The headlights and generator were obviously swapped out, but even the heater motor and wipers worked fine when run at 12V from 6.

I would talk to an experienced mechanic who knows the ins & out of the 356, but you might find that it is easier than thought to convert to 12V.

Incidentally, prior to converting to 12V, we used (2) 6V batteries wired in series for starting and charging, but only one battery was used to supply 6V to the truck. This setup was both complicated and unreliable, so I would not try any tricks. I would just convert or buy an Optima or Odyssey 6V if you choose not to convert.

troos

Amen to the Optima. It won't help much, though, unless the grounds and old connections have been cleaned up.
About the 8 volt. You would actually do some damage in the long run. Perhaps just burning out bulbs, but perhaps more invasive also. I would seriously question any mechanic that made that suggestion. Sounds like a guy that favors a patch over a proper fix.
Tom
'97 C4S
'64 SC Coupe
'59 Convertible D

Steve Jensen

Do it right - get your connections clean, your regulator in tune (so it charges at the proper 7.2something volts), and if it is still hard to start, get Joe Leoni's starter relay. And headlight relays.

I had an 8v in my car for a while, its just a "lazy" step. Worth it to do it proper. Also, you'll be over working your generator and regulator to keep it charged... or you'll have an always undercharged battery. Had to replace 2 turn signal switches because of it.... and at $350 per pop (only found 3 in the country, 350, 350, 400), it is *much* better to just do it proper.

FL-356C

luvmy356, is there a certain model # of Optima that is best for our cars, or do they have just a general 6 volt?

luvmy356

I think they have only one size for the 6v version. The 6v Optima ts half the thickness of a regular battery and slightly wider. There is also a fake 6v battery shell that you could stick your optima in so that it looks like a standard 6v battery.

There are a couple of vendors that advertise the battery and cloaking device on the 356 registry magazine. The battery is about $150.

ked

btw, the Optima 6V isn't magic - any quality 6V in good shape, that meets the OEM spec, & is properly installed will do. the Optima is nice (to me, I've got one in my 911) because it is lighter than an old-tech batt and won't leak.

Steve Jensen

ked - Optima has 800+ CCAs, the "standard" 6v battery my FLAPS carries only has 600....

jcjblo

Could you tell me more about Joe Leoni's starter relay - my 356 is hard to start despite new ignition items (plugs, points, condenser etc.) Sometimes it almost drain the Optima to fire properly.
Thanks

luvmy356

Are you sure its not a fuel issue? Zeniths are known to evaporate the fuel out its bowls. and on some cars, the engine needs to crank a long time for the fuel pump to refill and start.

If I haven't started my Roadster for a week and I don't want to exercise my Optima, I will take the air cleaners off, and squirt a generous amount of carb cleaner down each carb, put the cleaners back on, and start the car. It will always fire right away, and have enough fuel to turn the engine enough to refill the bowls and continue running.

My Speedster has an electric fuel pump. I just turn on the ignition, and once the the pump clicking slows down, the bowls are filled and the car starts right away.

ked

http://www.356electrics.com/
I haven't dealt w/ Joe directly (yet!) but I've seen his documentation (amazing!) and his attitude & references (via the Registry) are absolutely sterling - he is quite approachable - his products address specific known issues, they work, they aren't outrageously expensive. I wouldn't hesitate to contact him directly.