Did I ruin my ignition system?

[volundur]

Hi experts and thanks for your wonderful information on chrysler outboards, Ive been reading this forum since I got my 1979 70HP SKIER last summer.

I just got it back from rebuilding and had it running two days ago, some minor touchups were left on my list after I had gotten it running and one of them was to make sure all connections were solid and good. The previous owner changed the distributor, and the old one seems to have had two terminal on the distributor's body, one for blue and one for white / black.

The new distributor has a single connection and both the blue and the white / black were hooked up to it, the blue one was not connected to the terminal until last night when I looked over wiring diagrams and decided to connect this lost blue wire to the ignition terminal.

Tonight I wanted to get the motor running to break in new pistons and it wouldnt go, cranks fine and everything seems to be in order except I get no spark on any of the plugs.

After going over the whole thing again and again I realized that I have probably introduced the distributor / CD module to a hot wire where it wasnt appropriate, so I ask you guys if I might have shot the CD module or the distributor?

I know it's stupid of me to hook the wire up, but since the engine has a few other things that dont measure up to my wiring diagram I thought it would be safe to assume that this blue and lonely wire had been missed when the engine was reassembled after the rebuild.

Thank you so much for your time and info.

This is the diagram for my engine, it has a single terminal distributor body.


This is a photo (I found it on the forum) of the same distributor that got replaced by the PO, but he seems to have hooked both of the wires to the single terminal body, leaving the other end of the blue wire loose at other side / main terminal.

 

[Frank Acampora]

Re: Did I ruin my ignition system?

The distributor with two terminals is an electronic distributor with an electric eye inside to signal the CD box to "dump" the capacitors into the coil.

The single terminal distributor has a set of points inside. When the points close. the transistor inside the CD box goes to ground and is signaled to again dump the capacitors.

As far as I know, the CD box for both systems is the same. I don't know how the electronics inside differentiate between going to ground and recieving a voltage signal from the electric eye.

NOW: The electric eye probably does NOT generate 12 volts signal and by putting 12 volts through the black/white wire it is possible that the transistor will be burned out.

At any rate, the single terminal distributor should have ONLY the black/white wire from the CD box attached. The blue wire is a power source to the lamp in the electric eye of the electronic distributor and should be disconnected from the terminal board and the single terminal distributor...

Try firing the engine. It either will work or will not.

A simple test is to remove all the plugs and ground them. Then turn the flywheel slowly by hand with the ignition ket on. If the plug has one sharp snap with a spark, the ignition is good. If the plug goes Bzzzzzzt with multiple sparks, you have ruined the transistor inside the CD box. Throw the box away and buy another--they are not economically repairable.

Understand that there are three wires comin from the CD box to the terminal board: White which is a tachometer signal, red which is constant power to the capacitors inside the CD box, and blue which is switched power to the electronic circuits inside the CD box. These three wires do need to be connected to their respective terminals on the terminal board.

 

[volundur]

Re: Did I ruin my ignition system?

Thank you so much Frank - I'll perform the test tonight if I find time. I tried firing the engine last night, but it didnt respond at all.

For the record I tried the old CD box (condition unknown) and it gave the same result

can you inform me on one more thing Frank?
- what is the small piece of electronics inside the distributor box that seems go open and close when the axle of the distributor is turned called? - the one the black / white wire connects to? Is it possible that I fried it when hooking it up to 12v?

All the best and great appriciation for your time.

 

[Frank Acampora]

Re: Did I ruin my ignition system?

That is called the "POINTS" It has a set of tungsten contacts on the arm and base so that the contacts will not pit and wear from the electrical sparking as they open and close. The opening and closing of the points is what times the spark and sends it to the correct sparkplug.

Even though the points on your distributor do not get sparking as they open and close, they still can get dirty from too much oil on the lubricating wick and can get corroded from just sitting. SO: periodically points must be cleaned and gapped. And no, you could not have damaged the points by putting 12 volts to them--they were designed to handle that much voltage.

To clean them, spread them open and (best) using a points file, let them snaop closed on the file and work it to clean them. You can also fold some fine 200-400 grit wet/dry sandpaperinto a small double sided piece and let the points snap shut on it. Then pull it out. Do that several times until the contacts are shiny and smooth.

Point gap on a three cylinder engine should be set to .014 inch open on a high lobe of the cam. You sound non-American so you would convert that to metric. I forget the exact conversion but you should be able to google a conversion chart.

 

[Nordin]

Re: Did I ruin my ignition system?

Sorry to say but I think you have fried the CD. MagnaPower CD with points and with preamp are the same you can use both of them to the CD.
With points the CD module transistor that controls the capacitor is blocked when the points is closed.......ground signal to CD.
When points open the transitor open the gate for the capacitor to dump voltage to the coil.

The preamp act as the points but you have a feed voltage 12V, blue wire and this voltage is just for the preamp. When a window at the rotor uncover the preamp it open and unground the signal to the CD module.

BTW: 014in = 0,36millimeter

 

[volundur]

Re: Did I ruin my ignition system?

Thank you for the information. Is there any way to test the CD Module?

We tried your test tonight Frank, but there was no spark at all coming from the sparkplugs, we grounded the plugs as you succested, but there seems to be no juice coming from the distributor.

Here are some pictures of meterings done with a multimeter tonight, it shows 6.4v current between the poles on the coil and a steady 12v on the black / white wire. Can you make anything of that?

Thank you so much again.



*edit* we figured that the CD module was not properly grounded, after we grounded it we get no voltage when measuring as on the pictures below.




On the last one we measured the voltage on the black / white lead which was accidentally hooked up with the blue terminal on the terminal board.

 

[volundur]

Re: Did I ruin my ignition system?

We also measured the voltage on the blue terminal while cranking the starter, it read 9.8 steady while starting.

 

[chrome dome]

Re: Did I ruin my ignition system?

if the CD module is cactus but the dizzy is ok could he not just put a 12v car type coil and dist mounted condenser
in place of the expensive (if he can find one in good nick ) CD module?

we've just obtained one ( 105 ) with this on it...seems to run well

edit..oops...slow typer on board LOL

 

[Frank Acampora]

Re: Did I ruin my ignition system?

Nohing should be between the negative and positive terminals on the coil until the capacitors dump their voltage. Then, there should be a 12 volt pulse to the positive terminal. This pulse should be so fast that a regular multimeter should not be able to capture it. If you are getting a constant 6.2 volts at the positive terminal as shown in one of the photos, then there is a short in the CD box leaking current. Thus in all probability, it is bad and needs replacing.

Since the two terminals of the coil ar the ends of the primary winding, putting the meter leads across them should result in no measurable voltage but you should be able to read low resistance. In order to measure voltage to the coil you need to either disconnect the ground wire from the block or the power wire to the positive side. THEN, measure from either negative terminal to ground or if you removed the positive wire, from positive wire to ground. If you do not disconnect either terminal, voltage will run through the coil in addition to through the multimeter giving a false reading (because the coil primary resistance is so low)

The voltage will be a short, sharp 12 volt spike as the capacitors dump. THIS IS THE REASON FOR CAPACITOR DISCHARGE IGNITION: Capacitors discharge so quickly that the coil primary is very quickly saturated, generating a stronger magnetic field than a points and battery ignition. Then the pulse is so short that the magnetic field, which is stronger, collapses more quickly, generating a higher spark voltage.

 

[volundur]

Re: Did I ruin my ignition system?

Nohing should be between the negative and positive terminals on the coil until the capacitors dump their voltage. Then, there should be a 12 volt pulse to the positive terminal. This pulse should be so fast that a regular multimeter should not be able to capture it. If you are getting a constant 6.2 volts at the positive terminal as shown in one of the photos, then there is a short in the CD box leaking current. Thus in all probability, it is bad and needs replacing.

I have to update the information on our readings: we figured that the CD module was not properly grounded, after we grounded it we get no voltage when measuring as like we did in these 2 photos.

So I should really just start looking for a new CD module? the funny thing is that I have another one lying around, but after testing it yesterday it seems not to function eather. I'll try some of the test you succest on the weekend Frank.

Regarding the cheaper way Chrome Dome talks about I guess I would be happy to try it - there is no change of getting parts here in Iceland, so I would always have to buy on ebay and wait a couple of weeks : ) - Do you have more info on the setup Chrome Dome?

 

[chrome dome]

Re: Did I ruin my ignition system?

we got our 'inspiration' from the link below, also from here at iboats as well as a local who does a bit of work on these old girls,
1969 Chrysler 75 HP Outboard Ignition Coversion - SmokStak
just pay a bit of attention to how it's wired up to coil and dizzy/condenser,
if you need more info on that just ask
you may have to change the ignition switch wiring too...haven't looked at the diagrams so can't be sure

had ours for less than two days...bought it for an ignition system swap to a 120 but a blown head gasket has put that on the backburner, plan A turned into plan B, we'll wait and see if plan C is needed down the track

anywho, this 105 just has a 12v car old type coil, points dizzy ( one terminal ) with condenser mounted on it and the rectifier/voltage regulater,

essentially,it is 'going back' to battery ignition with a later model rectifier,different coil and the points are in the dizzy

 

[volundur]

Re: Did I ruin my ignition system?

Great news! We performed the tests Frank descriped, finding that we got no spark at all, replaced the CD module with the spare one we had (older one from the original ignition system) - after i bit of thinking and reading online we got to the conclusion that the points was to blame. After removing the distributor and cap and analyzing the points it came clear that the red piece of plastic that insulates the ground from the signal wire (white/black) had melted and disconnected the nuts and washer inside. See the pictures below. Now it starts and we can keep on restoring : )

Thank you very much for your help, we really got a chance to learn about the ignition the hard way!

V?lundur and Kjartan.


closeup

 

[volundur]

Re: Did I ruin my ignition system?

Even got a video of it running! 1979 Chrysler 700 Skier outboard - YouTube