I backed my 61 F85 into the garage. Over a period of time (2 months) I changed the intake manifold gasket and valve stem seals. Now it will not fire. I did pull some wires apart apparently . To the coil there is 2 wires that looked like they go to the - side of the coil, a brown one and a black one. The brown one is defiantly hot hot with ignition on. Im not dure where the black one goes. They are wrapped in harness. There is weak spark at the points and at one of the plugs i checked. I did change the coil. Didnt change anything. Any help would be appreciated..thanks

 

I had this issue awhile back......I ended up finding I had nicked one of my coil wires in a place I could not see. Good luck!

 

The negative side of the coil only gets a wire from the distributor and a wire from the noise suppression condenser on the side of the coil. The plus side of the coil also gets two wires, one that is hot (+12v) with the key in the START position and the other that is hot (+9v through the resistor) with the key in the RUN position.

 

Where is the 9v one coming from?

 

It comes from the bulkhead connector. The other is from the starter.

 

Actually, the 1961-63 cars don't have a bulkhead connector. The harness has so few wires that it is one piece from the fuse box and simply passes through a grommet in the firewall. Since the car is unibody, it didn't make a lot of sense on the assembly line to have a separate underhood harness - the inner fenders don't come off.

 

i guess thats the two i have hooked up. those were the only 2 in the are. completely replaced the one going from coil to distributor. still wont fire..

 

I failed to mention that this car has an alternator instead of a generator. I don't know if that matters, but there was no wire on the starter "r" terminal. I have apparently burned up the starter now, but when I get it back fixed do I need to run a wire from there to the coil?

 

Sounds about right, for sure there is supposed to be a wire from the starter solenoid's "R" [Resistor Bypass] terminal to the coil + side. Typically yellow on the ones I am familiar with.

Oh, and
"I did change the coil. Didnt change anything."
means that you put a different coil in, but that did not make it better?
Have you replaced the points and condenser lately? Checked the point gap? Ck the distributor shaft for side play?

I took apart some old distributors recently and found that the upper bearing "grease" was no longer anything at all like grease. That leads to fast shaft and bearing wear, which then alters the point gap as the engine runs, which alters the timing. Not good.

 

I wonder what the other wire is to the coil + if it was not the one from the starter?

 

yes..new coil, points,condensor. no change in situation.

 

good question..guess ill be chasin wires now..

 

If you install a jumper wire from the + side of the battery to the + side of the coil, it will eliminate everything from the key to the coil. Then all you have to do is turn the key and the car should start. Note, in order to shut it off you have to remove the jumper.

 

I was just about to suggest this - you beat me to it.

To clarify, the jumper bypasses the ignition switch terminals and wiring that power the coil. You're still using the switch to activate the starter.

If the car starts with the jumper, you've isolated the problem to the ignition switch or related wiring to the coil. If it still doesn't start (or doesn't produce a spark), you have other problems.

 

thanks. ill give that a shot as soon as i locate a starter..

 

Not to bust your chops, Joe, but the RF suppression condenser goes between ground and the (+) terminal of the coil.

The only wire on the (-) side of the coil is the wire to the distributor, plus a wire to the tach if the car has one.

The ignition condenser does, in fact, bridge from the (-) coil terminal to ground, but it does so inside the distributor, to make a better spark and protect the points, and not to suppress RF interference.

I don't want to confuse this guy.

- Eric

 

i stay confused..lol..would the condenser on the wrong side keep it from running?..i tried the wire straight to he + side of coil, still cant get it to start.

 

If you had a wire direct to the coil then your issue is coil, points, or condenser. Or the wiring in between. The jumper isolated everything else. Did you set your point gap to .016 which should allow it to start?

 

Two capacitors in parallel, if I recall correctly, results in simple addition of their capacitances, so, yes, it would probably run, though the inductance / capacitance resonance would probably be off a bit.

Why would you want to connect it wrong, though?

To review:

• +12V to the (+) coil terminal (probably through a ballast resistor - I'm not familiar with the details of that year, but GM tended to use ceramic firewall-mounted resistors at that time).
• (-) coil terminal connected to points and condenser, which are inside of the distributor

.
If all is well, you should get a spark.

- Eric