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Tue Mar 01, 2022 10:22 am

72 beetle would drive but rear main seal needed replaced I pulled the engine and re installed. Started hooking everything back up however when I hooked the wires back to my ignition coil I put the hot wire to the number one post (neg) when I went to turn it over it complete melted the ground coming off the condenser.

I replaced the ignition coil and replaced condenser. Now i get no spark at the coil. Coil is getting 10.4v and when i have the key in run I get about half that to the negative.

Any ideas what could be wrong now. Did this mistake cause something to burn up/need replacement.

When I hook up the positive wire to the coil I can hear audible clicks on the carb so I know the remaining wires on the coil are good.

Tue Mar 01, 2022 11:57 am

whats the voltage at the battery? check continuity of the rotor some rotors have a resistor in them. have you checked resistance of the coil primary and secondary side?

Tue Mar 01, 2022 12:42 pm

Battery: 12.5v
Coil 3.6 so good coil
Wire has 12.5v before hooking up to coil after hooked up drops to 0v

If I pull on the ground running from negative to distributor I get 11.4v across the coil and I can hear some spark at the distributor but then it drops back to zero.

Could this mean the distributor has bad ground? I don’t want to keep throwing parts at the problem.

Tue Mar 01, 2022 1:12 pm

You might have killed the electrical part of the ign. switch. Try running a jumper from license plate light to coil +, turn on parking lights and try to start, if it starts and runs it's the ign. switch (turn lights off to stop motor).

Tue Mar 01, 2022 2:02 pm

Not understanding the point of the jumper off the license plate light. When I have getting 12.5v when I turn the key.

Could you explain.

Tue Mar 01, 2022 2:15 pm

SirIsley72Beetle wrote: Not understanding the point of the jumper off the license plate light. When I have getting 12.5v when I turn the key.

Could you explain.

10.4 v is too low indicating ign. switch got fried, a jumper of 12v to coil will start the car. Remember the + wire to ign. switch is UNfused so no fuse to pop and ign. switch contacts are thin brass. Check the volts at the coil with switch in the start position.

Tue Mar 01, 2022 2:23 pm

understand that would be too low, 10.4 is what the coil is indicating the positive hook up is 12.5 however. assuming that would be a grounding issue in the distributor since when i turn the key the coil is being supplied 12.5 but when checking the voltage on the coil from the pos to neg it is only indicating the lower number

Tue Mar 01, 2022 2:30 pm

The - on the coil should only have one wire and it should go to the distributor (unless you have a tach.) the distributor grounds to the motor and the motor grounds to the battery through the front trans. ground strap.

Tue Mar 01, 2022 2:34 pm

yes i have one ground coming from my distributor(through the condenser) on the negative side of the coil

on the positive side i have two wires going to the carb and the 12v wire

Tue Mar 01, 2022 2:46 pm

Have you looked at the points to see if they are OK?

Tue Mar 01, 2022 2:54 pm

When I start my car I am always looking for 12V at the coil. Turn the ignition on. Test the voltage at the coil. It should be 12V. Otherwise car may not turn over.

Is your car turning over at least? Is the starter running?

If the wire melted I'd say put a new condenser and points on it. The points may be good or they may fall apart as you drive down the road.

Tue Mar 01, 2022 3:13 pm

So given the state of the pics easy to say that’s my issue. My next question is should I replace the points or given the fact that I fried them seeing that all I smell in the distributor is melted plastic in the distributor do I now need a new distributor?

Tue Mar 01, 2022 3:17 pm

Points look melted. I'd replace them. Running electricity through a distributor will not ruin it. It will only affect the points and condenser. Those are the only components you need to replace, if any. You do not need a new distributor because of this.

Tue Mar 01, 2022 3:23 pm

Will be replacing tonight and will update if my problem is solved…thanks for the assistance!

Tue Mar 01, 2022 3:36 pm

heimlich wrote: Points look melted. I'd replace them. Running electricity through a distributor will not ruin it. It will only affect the points and condenser. Those are the only components you need to replace, if any. You do not need a new distributor because of this.
Unless you do such a spectacular job you melt the braided strap between the breaker plate and housing, I don't see it in the pics, how does it look SirIsley?

Tue Mar 01, 2022 4:48 pm

busdaddy wrote: heimlich wrote: Points look melted. I'd replace them. Running electricity through a distributor will not ruin it. It will only affect the points and condenser. Those are the only components you need to replace, if any. You do not need a new distributor because of this.
Unless you do such a spectacular job you melt the braided strap between the breaker plate and housing, I don't see it in the pics, how does it look SirIsley?

As it looks like a 009 breaker plate (or simular mechanical advance only distributor) it never had and don't need the braided strap. The fixed plate ground just fine with the screws holding it to the house.

Tue Mar 01, 2022 5:30 pm

Frederik wrote: busdaddy wrote: heimlich wrote: Points look melted. I'd replace them. Running electricity through a distributor will not ruin it. It will only affect the points and condenser. Those are the only components you need to replace, if any. You do not need a new distributor because of this.
Unless you do such a spectacular job you melt the braided strap between the breaker plate and housing, I don't see it in the pics, how does it look SirIsley?

As it looks like a 009 breaker plate (or simular mechanical advance only distributor) it never had and don't need the braided strap. The fixed plate ground just fine with the screws holding it to the house.
Ahhh yes...., I see that now, but for future searchers with similar problems a vacuum advance model may not survive a miswiring event so well.

Tue Mar 01, 2022 7:12 pm

Okay so update, have the new points in and that fixed my grounding issue because the last was burnt up. So, key in off 0v on the coil, key to start 11.4v on the coil when testing positive side with negative. Already confirmed it is being supplied 12.5v from battery still no spark.

Any ideas now?

Tue Mar 01, 2022 7:16 pm

Did you adjust the points when they were at the peak of a lobe on the cam in there?, what happens if you connect a test light between the 2 primary terminals on the coil and crank?, steady light?, or flashing?

Tue Mar 01, 2022 9:52 pm

Did you replace the condensor?

Did you remove everything connected to the coil except what is necessary (eg no back up lights or reverse lights)?