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Wed Mar 17, 2010 4:43 pm

Every time I try to start my engine I burn my condenser and the points. The wires melt. I had my distro hooked to the #1 terminal on my coil and the 12v to the #15 terminal. This has happened twice and I only have one set of points left so what am i doing wrong. :?: :?: :?:

I dont plan on trying my last set unless i get a diffinetive answer.

Wed Mar 17, 2010 5:01 pm

Something is wacked out here..... are you sure you are hooked up this way?

Wed Mar 17, 2010 5:07 pm

yea except i don't have my reverse lights hooked up. Maybe im not setting the gap right.
Oh it only does this if it sits after i turn it over.

Its odd because when i had the engine out of the car it worked just fine. Then i put it back in and poof went the wires. [/img]

Wed Mar 17, 2010 5:31 pm

What coil do you have? More importantly... What is the resistance across the #1 & #15 terminals? This is the primary circuit.
Stock coil should have 2.5 to 3-ohms of resistance. Less is bad and can burn up points by running too many amps thru the points/condensor.

Wed Mar 17, 2010 5:36 pm

It might be the coil its kinda battered and beaten ill have to get a meter to check.
Its definitely running to many amps cause the wires just fry.

Thu Mar 18, 2010 9:55 am

It has 4.4Ohms across terminal 1 and 15 so its still good right? Its a Bosch coil btw.
Could i put a fuse between the coil and distributor to keep it from frying everything when i try again.
I should have said this earlier but my coil is directly connected to the battery, could this be the problem?

My engineering teacher said to look at the rotor but i dont think that would be a big deal would it?

I really need some help anybody in south Florida.

Thu Mar 18, 2010 5:35 pm

so am I going to need to get a new coil anybody?

Thu Mar 18, 2010 11:38 pm

The coil should never be energized unless the the engine is running or
starting.

Fri Mar 19, 2010 2:39 am

cdxanti wrote: Oh it only does this if it sits after i turn it over.
What do you mean? If you run the motor at 35mph for hours the points are fine but if you come to a stop the points will burn up?

4.4ohms is high.
Are your contacts clean? Was this with nothing else connected to the coil? Did you zero your ohm meter?
What is the resistance between the center post and either +/- terminals? It should be in the 10,000ohm range.

You can add a fuse to the + post of the coil. 5A should be fine.

Fri Mar 19, 2010 9:03 am

cdxanti wrote: I should have said this earlier but my coil is directly connected to the battery, could this be the problem?

so, when it hasn't been running it is still connected straight to the battery?

Fri Mar 19, 2010 10:01 am

Quote: Are your contacts clean? Was this with nothing else connected to the coil? Did you zero your ohm meter?

No ill clean them, yes their was nothing else connected, yes the ohm meter was zeroed.

Quote: so, when it hasn't been running it is still connected straight to the battery?

No im rewiring everything its only connected when im trying to start it. Just the coil, choke, etc. and starter are connected. just what I need to start it.

Quote: You can add a fuse to the + post of the coil. 5A should be fine.

Could i put one on the - side to protect the points and condenser or does it fluctuate to much for that.

Fri Mar 19, 2010 12:36 pm

cdxanti wrote:

Could i put one on the - side to protect the points and condenser or does it fluctuate to much for that.

Fusing the ground side of a circuit serves no purpose. A fuse is used to stop excessive current flow.

The points ground the coil to allow the field to build. You will notice if you check the coil with a testlight clipped to ground that it will light up on both coil terminals WHEN the points are open. Do not be confused with this, it is normal as the current going through the coil is looking for a path to ground.

Get your coil hooked up to your ign switch instead of going directly to the battery. The way you have it if the points are closed not only will it heat up the coil but your points will burn.

Fri Mar 19, 2010 1:20 pm

but i should still get a new coil right? So a 5 amp fuse would work to protect everything?

Fri Mar 19, 2010 1:39 pm

cdxanti wrote: but i should still get a new coil right?

No. The resistance you measured, 4.4 ohms, is a little bit higher than expected. Which means that the current it will draw is LOWER, which means that's not your problem.

You said you're doing wiring. What gauge of wire are you using from the battery to the +15 terminal on the coil?

Fri Mar 19, 2010 2:28 pm

Quote: What gauge of wire are you using from the battery to the +15 terminal on the coil?

Its the regular wire that's in the harness i just rerouted it.
Its odd cause I am doing everything the same way as when i had it out of the car.

Fri Mar 19, 2010 2:30 pm

Oh I just figured out it only burns the wire when the points are closed maybe that helps.

Fri Mar 19, 2010 8:18 pm

cdxanti wrote: Oh I just figured out it only burns the wire when the points are closed maybe that helps.
No, that doesn't really help. We assumed that.

Sun Mar 21, 2010 4:34 am

So you have your ignition wired straight to the battery (not thru the ignition switch). This by itself should not be a problem.
But how long do you leave this ignition circuit connected with the engine NOT running? A minute should be okay, but if your points happen to be closed and you leave the ignition circuit connected for longer... points and wiring may start to melt.

Could this be the cause of your problem? Wire a switch between the battery and the coil to simulate the ignition switch so you and turn OFF the ignition when not in use. Or be sure to always disconnect it.

EDIT: Putting the fuse on the - side of the coil doesn't offer more protection, it actually offers less. Should a wire that comes AFTER the fuse contact ground, it would cause a surge of amps and blow the fuse. If a wire from BEFORE the fuse contacts ground... the amps will still surge but the fuse will not blow. So in your suggested configuration, if there were a short of the coil, the fuse would not blow.
Place the fuse as close to the + source as possible to protect the majority of the circuit.

Sun Mar 21, 2010 10:53 am

Ok i was just out their wiring the switch in and the wires before the coil are all melted too. do i still have the same problem?

EDIT: btw i thought that when the ignition sw was in the on position the coil was on. which would mean that if you left it in the on position and the points were closed it would fry them anyway. I am unsure of how the stock ignition works so please correct me if im wrong.

Mon Mar 22, 2010 8:16 am

Not a good sign. This means the short was THRU the coil and all wiring between the battery and the points heated up and melted. There's a chance the coil primary wiring may have been damaged as well.

Leaving the stock ignition ON for any extended duration with the engine NOT running is not a good idea... it will melt points and the ignition wires that power the coil. So listening to your radio while parked and engine OFF is not a good idea. Some have gone as far as making an Accessory circuit which powers the radio w/o keeping the ignition ON.

Is there any chance you left your make shift ignition connected for any length of time while the engine was NOT running?