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Timing 1951 FL

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King
Posts: 387
Joined: Fri Apr 02, 2004 5:05 pm

Timing 1951 FL

#1

Post by King » Fri Sep 10, 2004 2:40 pm

I just finished timing my 51FL with the single breaker point set-up. As usual I followed the manual and got the old dear back to starting a bit better. But I noticed with the lights out a lot of arcing around the points so suspect the capacitor is shot. I've run out of the stash of capacitors I bought years ago so is there a capacitor you can get from the local auto store that will do the job?
By the way, my manual neglects to tell you turn on the ignition when you do the test light thing.
Interestingly enough I just finished the job when my copy of American Iron arrived. In this issue Donny Petersen has an article entitled “Starting a Panhead". I found it pretty informative he goes through the timing routine and discusses plugs, carbs, and clutch adjustment etc. But it raised a question. He implies that the points capacitor handles the high voltage. He warns that a coil for an electronic ignition setup (only with a 12 volt conversion) producing 40k volts will burn out your capacitor as it is only designed to handle around 20K. I thought that the capacitor was in the low voltage portion (in my case 6V) of the system, is it??
Also I got to say it, Donny it's a CIRCUIT BREAKER not a distributor. Maybe he used the word distributor as that is what most folks assume it is.
I found a tachometer that you can attach with zero effort. It's called the "Tiny Tach" and is about the size of a box of Tic Tacs. You simply wind its red wire around a plug wire and ground the white wire to the motor. It reads double of the actual RPM due to the lost spark effect but that's not a big problem and I understand that now they make one for lost spark ignitions. It's also an hour meter.

Ride Safe

King



Cotten
Posts: 6911
Joined: Mon Aug 26, 2002 9:09 am
Location: Central Illinois

Re: Timing 1951 FL

#2

Post by Cotten » Sat Sep 11, 2004 3:45 am

Wow I gotta try that turning on the ignition thing. I've been disconnecting the coil! (And yes, it is not a distributor, although the '61 to '64s came close. Indians had distributors.

kell
Posts: 404
Joined: Sat Jun 19, 2004 2:58 am

Re: Timing 1951 FL

#3

Post by kell » Sat Sep 11, 2004 4:23 pm

I'll put my two cents in about condensers. You are right about the condenser being on the primary (low voltage) side of the coil. However, when a coil fires, there is a kickback effect. It is called "back EMF." EMF stands for electromotive force, which just means voltage. This voltage coming back is what causes points, or any switch, to spark when they open -- at least if you don't have a condenser to absorb the jolt. It would come to a few hundred volts, more or less, not thousands. I'd have to think about it, but my guess is a coil with a higher secondary voltage -- that is, on the spark plug end -- would have a bigger jolt back toward the points as well. So Pederson may have a point, but I'm not sure it's such a big deal that you have to worry about it. An old condenser would fail because it's old, not because it has an inadequate voltage rating. That's my guess. And I also think any condenser made for a 12 volt system would work. You'd need to worry more about size and how to mount it.

haggis
Posts: 177
Joined: Fri Mar 19, 2004 3:35 am
Location: Maine USA

Re: Timing 1951 FL

#4

Post by haggis » Sun Sep 12, 2004 1:34 am

Kell,
Has anyone ever thought about putting a diode in place of the Cap' that would put the brakes on the back emf...like in Pinball kicker solenoids.Haggis

kell
Posts: 404
Joined: Sat Jun 19, 2004 2:58 am

Re: Timing 1951 FL

#5

Post by kell » Sun Sep 12, 2004 9:58 am

Not only thought about it, tried it on the bench. Killed the spark for some reason. One of the many occasions where electrical stuff did something I didn't understand.

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