120hp 1970(?) Wires to connect to start

[Captain Bravo]

I bought a 120hp Chrysler model 1207HA S#4997 from an auction. It has Magnetron ignition with points. All I got is the motor. I put it in a barrel and tried to start it but no spark. I checked out the points and was getting no electrical contact across them. Cleaned them up and they appear to be functioning properly and gapped correctly, but still no spark. (Plan to replace them, but just want to get it started)

I haven't seen a diagnostic flowchart for this ignition, but I did find a diagram. I don't have the wiring harness or switch. Are there any wires that need to be connected to get spark? Is there a flowchart for this ignition system somewhere?

http://www.maxrules.com/graphics/force/wiring/75-135_cdMagDelta.jpg

 

[Frank Acampora]

YES. If you do not have a wiring harness, you need to connect a couple of wires to power the ignition. Assuming you have Motorola Magna-Power ignition, you must at the engine terminal jump the red battery to the blue ignition wire. Typically, Motorola has two sources of power for the CD box: A red to red which is always hot if the battery is connected and this charges the internal capacitors. THEN blue is usually wired through the ignition switch This powers the electronic circuits inside the CD box.. In your case, because you do not have the wiring cable you simply connect the blue to the red terminal on the engine board. HOWEVER: To stop the engine you must disconnect the blue.

On this engine, points do not work like on a regular auto engine. The points simply signal the CD box to dump the capacitor's stored power into the coil.

 

[Captain Bravo]

Thank! I'll go try it.

 

[Frank Acampora]

Forgot to mention: Because the capacitors are always wired to the battery, IF the battery has been disconnected for a while, when you do connect it you will get a spark as the capacitors charge. Nothing to worry about.

 

[Captain Bravo]

Yes I did. I didn't realize there were capacitors. I was just surprised that it drew that much power. Good to know that it normally doesn't draw that much.

I do have spark now. It fired several times but didn't start. I was going to do a compression test but realized that my tester is at a friends house. I also noticed that there was gas leaking from some of the crankcase(?) lines. 1/4" vacuum lines that run to various parts of the crankcase.

So, I am out of time today, but the next step is to replace all the soft lines, clean the carbs, check compression. So far it looks and sounds pretty good.

Thanks a lot for the help.

 

[MickLovin]

Possible fuel pump diaphragm problem if you are getting fuel into your crank.

 

[Captain Bravo]

I'll check that too. Thanks for the help.