Won't Start
 

I have my car on a trickle charger and when I start her right after she has been on it she starts pretty much right up. I then can turn the car off and she wont start. Car is still cold and even after a short spin. Some symptoms when I turn key are lights do dim a liitle, slow turn over, must press in clutch to start sometimes. What are some suggestions new generator,grounding straps, problem at carbs? I have checked the baterry connections for corrosion and they are clean. Help!!!!

Sounds like a bad battery but maybe not. Test voltage at battery ... running volts should be about 2 more than not running. A little known fact : cars with healthy generators will run without a battery. If all tests well then trace cable from battery to starter and ignition to solenoid. resistence in wires or a tired starter motor can eat up a lot of amps.
good luck

Start with easy first. Try a good battery. If still have problem do a cranking voltage test at the starter. Look for a difference in the battery voltage -battery to ground- and the big + connector on starter to ground- read both while cranking the starter. If there is a sizeable drop/delta then check and clean all connections from battery to the starter including the ground strap. Rare but swag on wire connectors can sometimes look good but be corroded inside. 912s use mechanical regulator but more modern electronic voltage regulators will fry real fast if run without a battery connected.

Alex,

Check the ground strap down on the tranny, toward the front of the car. This thing gets tons of road crap built up on it. Take it off and soak it in a solvent to clean off the grime build up.

Clean and sandpaper all your ground connections at the battery, engine compartment, tranny etc.

It sounds like you might have something shorting straight to ground.

Craig

I am going to try and recharge my battery and see if that works using a god battery charger. I am planning on doing my spring tune up work putting on new valve cover gaskets and starter relay for hot start problems I have had in past. So while I am at it I will see if there is any thing else that it might becausing the no start. I want to thank everyone for there help and I will try all suggestions if its not the battery.