61 Bonneville.....no start...no crank...
 

Dead stock 61 survivor...all original except for alternator conversion....(with voltage reg)

Other than horn....everything electrical is not working.....no headlights or dash indicator lights...with key in crank position...

Starter will crank when I run a jumper to purple wire terminal on horn relay....

I just by-passed neutral safety switch....and still nothing....

What next....ignition switch?.......Anyway to test other than replace?

Any input is appreciated..

Since you did an alternator conversion I'd say start there?
12 volts to alternator?
Where does the big red wire on alternator go to?
How did you wire the conversion?

Check for 12 volts at fuse box?

Battery + cable go to the starter still? Power wire from there to power post? (probably horn relay or something?)

:confused:

A volt ohm meter, or a test light, is a helluva lot cheaper than buying parts, and throwing them at a car, only to have changed everything that bolts to the electrical system, and find that corrosion, or a loose connection is causing the problem. As a rule, I never change anything electrical until I've isolated the problem to that part, saves me, and customers money, and grief.

I've seen more than a few GM cars that the small wire (purple) that energizes the starter solenoid is either is loose at where the nut is not tight enough for a good connection, or has corrosion under the terminal.

If the wiring is original it can be in the bulkhead connector connector where it passes through the firewall. Any wiring though could be suspect if it's original to the car, but even new cars have wiring problems occasionally.

That's how I solve electrical problems after twisting wrenches for a few decades. YMMV...:D

I checked and cleaned the purple wire terminal.....but it really had no evidence of corrosion ...and was tight.....

I'm thinking that these early B bodies do not have a bulkhead connector.....Underhood wires just pass thru firewall to fuseblock...IIRC

In case you don't have one, here's a copy of the 1961 wiring diagram. http://www.oldcarmanualproject.com/t...re5765-333.jpg

It's not clear - did the car work, then you did an alternator conversion, and then it didn't work? If that is indeed the case, tray backtracking the changes made to the wiring.

If that isn't what happened then I'd suggest starting with something fairly simple. For instance, the headlights should come on whether the key is on or not, so check to see if +12 volts is getting to the headlight switch and go from there.

Alternator conversion was done a year ago..by previous owners shop...

Look professional....not a hack job...

Thanks for posting wiring diagram..

Check the connections at the amp gauge . Had the same issue.

Or the big yellow wire that goes to the amp gauge from the horn relay on the driver's side fender well.

As others said, plus the original regulator appeared to have a fuse, is there a fuse still in there somewhere?

Also appears the battery cable goes to the horn relay then the starter, still that way?

:confused:

Schematic from service manual:

Yes, the horn relay doubled as a big junction point for +12 volts.

There is good advice so far in this thread. When I bought my 62 Catalina 8 years ago, the only thing electrical on the car that worked was the starter and 1 brake light. The car did run. Nothing else electrical worked. Turned out to just be lousy connections at the fuse box and fuses themselves. I pulled the fuse box off the firewall, removed all the fuses and cleaned all the terminals with a Dremel tool and tiny wire wheel. Then new fuses and dialectric grease. Same with some light sockets, ignition switch, you get the picture. Everything came back to life and has been fine for the next 7 years so far. With your no start, follow the cranking circuit in the wiring diagram and clean everything, making checks along the way with a test light. Pretty simple circuit fortunately. Good luck.

Any update on this? Inquiring minds want to know. ;-)

I went through something similar with my '63 last year, which started as green fuzz on the fuel gauge wire. Several cleanings, ground straps, and volt/ohmmeter tests later, we were still not getting enough voltage at the input side of the coil. I picked up a NOS ignition switch (more green fuzz on mine), and voilà! Full output.

Grounds, though, are particular culprits in these cars. Everything runs to the chassis, and, well... 60+ years of accumulated rust, corrosion, and funk, and there goes the circuit.

I have found over the years that there is an awful load on the ignition switch. After you find your problem I would suggest moving some of those loads to a relay and dropping the current going through your switch.

Back to original post.
Horn and headlights are separate from ignition switch. Neither should be affected by switch position. If headlights are on when trying to start, they will dim due to battery load during cranking. But if they don't work at all that is a separate problem. In cranking position at the ignition switch there is no power to the dash gauges or indicator lights (except ammeter). So, if it doesn't crank but does when jumping at the solenoid that sound like a switch problem.