1972. Chrysler 105 no spark

[Leatherdog]

I have a 1972 Chrysler 105 with Magnapower ignition. I have cleaned all connections and performed the following test procedures and still cannot figure out why I still have no spark.
1. I have power to the starter and it cranks the engine.
2. Checked with inline spark checker on all plugs. No spark.
3. Used a 4 cylinder spark board. No spark jumping gap.
4. Checked voltage at blue wire which was 12.3v and cranking 21.1v.
5. Connected voltmeter to white/black wire while it was connected to the distributor and rotated engine by hand which went from 12.3v to 0.2v
6. Disconnected white/black wire from distributor and scratched it against ground and produced sparks but no sparks touching it to distributor housing?
7.connected DVA to voltmeter and checked gray wire going to CDI box and got 132.1v
8. Checked both sides of the breaker by terminal hub and had 12v on both sides.
9. Removed belt driven distributor. Used a points file to clean points and then did an ohms test while slowly rotating distributor (removed) have resistance when points close. Set gap to .10 and then reinstalled distributor lined up TDC and the curved line on top of distributor to the flywheel.
CDI makes high pitch noise with key on.
At a loss now as to why I have no spark. Any help would be appreciated.

 

[Leatherdog]

Not quite sure if the DVA voltmeter test was done right on the gray wire as i read that volts should be over 200v at cranking and I got with the Voltmeter set to 0v and the DVA plugged into the black com port and the red volts port. I also checked the interlock switch on the distributor which when depressed engine cranks and when pressed in does not crank.

 

[Frank Acampora]

The main clue is the high pitched squeal from the CD box when power is on. It should be quiet. The CD unit is probably no good and needs to be replaced Since the distributor is a points model you have the option of using a straight automobile coil instead of replacing the CD unit. Understand two things though: 1. The regular coil needs to be a 12 volt coil, not the usual 9 volt automotive. 2. The points and coil will not be near as good performancewise as the capacitor discharge ignition.

 

[Leatherdog]

The CDI box on the engine is the newer style sealed one. It is the 115-3301 vs the old style one and when i read the Seloc manual it says that it should make a high pitch squeal. It kind of sounds like a dog whistle. But who am I to say if this is normal since I got the engine with no spark to begin with thinking it would be simple to fix. Lol. I do have all the parts to convert it to automobile ignition but wanted to be sure it was not the points or rotor first before I converted it.

 

[Nordin]

Maybe I misunderstand you but in number 6 line you wright.

Disconnected white/black wire from distributor and scratched it against ground and produced sparks but no sparks touching it to distributor housing?

Does it produce spark when you scratch the White/black wire to engine ground BUT not when you scratch to distributor housing?
Then connect a extra groundwire from the distributor to the engine block or check the connection if there is a wire. Also check that your new CD box 115-3301 is grounded well. The mounting of the dist. maybe insult because of the grease in the swivel
Some of the old Motorola Magnapower box had a rubber mounting and if you use it the new box will have a bad ground connection.

 

[Leatherdog]

Yes i scratch the white/black wire to the engine ground and get sparks but I get no sparks if I scratch it against the distributor housing like the test calls for. I will check both grounds for the distributor and CDI box. I do appreciate all the help. Frank says the cdi box is not supposed to make noise which it surely is making a high pitch constant noise with the key in the on position. So does it not matter where exactly I ground the CDI box or Distributor as long as it is a verifiable good ground?

 

[Frank Acampora]

Good catch about the black and white wire, Nordin! The distributor body is insulated from ground by the grease inside it. If the ground is compromised the points, being grounded through the distributor will not work. On stock ignitions The coil negative is grounded to the side of the distributor mount (to the block0 and the distributor body is also grounded using the same screw. The CD box is grounded through the negative side of the coil (I think) Nothing says you can not run separate ground wires to a good block ground though, for example: A bypass cover bolt.

Just so you know for the future: The points in the distributor only signal a transistor inside the CD box to dump the capacitors into the coil. I forget exactly but either when the points open or when they close the transistor senses it and dumps. The advantage of a CD ignition is that the capacitors dump much quicker than a regular points and coil. There is no dwell to set. Because the voltage builds and collapses so quickly in the coil, the spark is much greatwer and has a sha

I have not used very many after market CD boxes and based my remark about quiet on the Motorola unit. If the manual says it should make noise then yeah, that should be correct (but Seloc has been known to be wrong on other things)

 

[Leatherdog]

I respect all of your replies and will thoroughly try them all. This is a project I am doing for my daughter who is serving in the Army. I call it project "Princess". I will check the distributor ground and CDI ground and move them to block if necessary. What I have for converting to automotive ignition if necessary is an Accel universal 12v performance coil with internal resistor pn# 8140C, Borg Warner condenser pn# G102A for the points. NGK 3922 BR6HS spark plugs. If I can get it to spark without the conversion I will just keep these parts in the boat for a
" just in case " situation. I will keep posting my progress. If I am missing anything from my list or troubleshooting procedures please let me know lol. You guys are great. I will post pics as soon as I can figure out how.

 

[Nordin]

Leatherdog and Frank, that CD box from CDI Electronics shall have a high pitch noise. I have that CD box on my 1977 75Hp Chrysler. Works perfect and have one in spare too.

 

[wickware]

No Title

Oops! I missed my info on limits.

Tips Uploading Pics/Attachments:

There are limits on sizes and number of attachments you can add (listed in the Forum).
1. I stay below 1 Meg on size (using window?s properties) if I point at my Pic to attach it shows the size.
2. I know I can attach 5 Pics.

Steps using Chrome since I c/n log-in using IE8.
1. Enter your Text at the bottom where it says ?Write something? (start typing)
2. Select the Camera?s Icon to start attaching
3. Below the Camera select upload
4. You should see a list of Folders and Files
5. Move too folder your Attachment is in, select it the with mouse (it hi-lit?s), select open
6. Select Unload More or continue (no more than 5 is my limit vs knowing
7. Your attachments should be showing below Upload More
8. Select Preview Post and if all is satisfactory, Select Reply.

What did I miss in this format that is new to me?
1. One question related to his points. Serving as a switch, is there a specific gap as .020?

 

[wickware]

Oops! I missed my info on limits.

 

[Leatherdog]

I appreciate and respect you all for the great advice. I have one week before I can get down to Northern Cali to work on the engine. I will post some pics I have taken so far asap.