1969 Engine Wiring Harness Replacement - will not fire

[Terry M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Thanks Terry. I'm not too sharp on the C3 cars when it comes to the physical details. That ground cable you mention is worth checking. Good lead.

What's odd is everything was fine until he swapped the engine harness. We'll see when he gets back to troubleshoot some more.

Rich

I agree it is a long shot Rich, but that 2 volt drop is a puzzlement. The C3 battery being behind the driver's seat has the negative lead attached to the chassis right under the battery case, and thus a good high current negative connection to the engine is needed. The C2 battery in the engine compartment uses a negative connection directly to the engine (I think, but my knowledge of C2s is minimal), thus no jumper across the engine mount.

I own two functioning C3s with TI, and another one under restoration and you are right on that with TI the battery has to be fully charged or you are SOL. Some of the aftermarket TI amplifier boards complicate the issue. Your systematic instructions are wonderful though. Keep working at it and all will eventually become clear. This is a great example of one member helping another and is what NCRS is all about.

[Peter S.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Just a Sunday morning thought here: Is the cable between the frame and engine (jumping over the passenger side engine mount) well connected?

BTW: This is a very nice systematic troubleshooting thread. Nicely done by both of you.

Ok Whenever you get back to it is fine. I think we're on to something. Best tool to check grounds is your ohm meter between frame and block. I think there's a separate ground from frame to starter, not sure though. Maybe the C3 experts can help with that.

Hope he does well at the game. Have fun. I love hockey too.

Rich

Hi Terry, Rich -

I spent a good deal of time today cleaning up connections. I did purchase 8' of 16-gauge wire, and also said, "what the hell.." and purchased a new starter. I just decided to install the new starter. Cleaned all wiring harness connections (though still nice and new) and applied dielectric grease.

I disconnected the ground from the engine block to the frame. When I restored the motor I of course painted it, but did not remove the paint in this location. So I ground the paint off to a nice, shiny finish. I measured the resistance in this ground cable - 0 ohms. I also ground the frame location to a nice shiny finish and reinstalled the ground cable w/ dielectric grease. Since this ground actually mounts to the starter bracket then to the engine block, I also ground both side of that bracket as well.

I then disconnected and pulled the battery ground. This also measured 0 ohms resistance. I cleaned up the ends and then also ground the frame location to a nice shiny finish, and reinstalled the ground cable w/ dielectric grease.

Battery is on the bench - charger says it's fully charged, which I measure at 12.8 volts.

I hope to drop in the battery sometime this week and remeasure our cranking voltage at the battery and wire. Hopefully it fires right up. I'll report back.

Thanks again for all the support!

P.S. hockey was fantastic - my son plays goalie and won both games, 4-3 and 2-1.

[Gary B.]

https://www.forums.ncrs.org/showthre...rease+Williams

Gary

[Richard M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Terry,

Yes the C2 battery ground goes directly to a starter attachment bolt. Some exceptions for C60 & some BB equipped cars iirc.
Good to know about the separate engine ground at the pass side mount. Another place for corrosion the add crank resistance.

Peter,

Good you cleaned the paint from the metal areas. That may be a major contributor to the lower voltages.

As Gary mentioned, careful with the dielectric grease. Best to apply dielectric after fastener reattachment. This will keep moisture away from the bare metal. I never use it at the connection itself as it is an insulator.

I'd hold off on a starter change until you get results from your work.

Check back in when you get time. To reduce battery drain, maybe skip the voltage tests at first to see if it simply starts. If not, then I'd revisit the testing and check back in.

Rich
PS Glad your son's games were successful. Fun times.

[Terry M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Rich & Peter
Another thought -- this time Monday morning:
I believe all those negative (ground) connections (three of them of Cs) have a "star washer" that is supposed to dig into the chassis and cut through the usual chassis coating that the factory used. In restoration we sometimes use more robust coatings -- we can't resist. But that "star washer" is supposed to be installed between the cable connector and the chassis. Some of us mistake that "star washer" as a lock washer and install it under the head of the bolt. The electrical connection will be improved if the "star washer" is installed between the connector and the chassis. In Pete's case, cleaning the connections well the location of that "Star washer" may not now matter so much. I know some chassis judges that check the location of that "star washer" in judging. It may not be worth a point, but it will get a note.

These high current connections must be properly installed to carry the load necessary to crank the motor; especially high compression motors with new rings and bearings.

[James G.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

I have been using this on my electrical connections for the last decade, it is specifically for bimetallic connections and prohibits galvanic corrosion.
I have all but eliminated faulty grounds and other electrical gremlins which were typically encountered when sorting out a restoration.

100_9577.jpg

I have kept up with this thread and I believe there is a mistake in the harness conversion.
What did you do with the original white covered coil wire in the repro harness?

Do you still have the complete original harness with which the engine ran correctly?

[Richard M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

The electrical connection will be improved if the "star washer" is installed between the connector and the chassis.

Terry,

Yes, always... Metal Hole - StarWasher - Ring Terminal - Bolt/Screw. Hopefully Peter has them that way. One thing I never got was why the designers didn't use the star-washers on some other very important areas on the C2's and I believe on some C3 areas. e.g. TI Module Ground, Voltage Regulator Ground, Core Support Ground. Points hit or not, I always added them for reliability.

.
.
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I have kept up with this thread and I believe there is a mistake in the harness conversion.
What did you do with the original white covered coil wire in the repro harness?

Do you still have the complete original harness with which the engine ran correctly?

James,

Because his car originally had TI, and still has his original TI harness, the stock points-ignition white resistor wire would not have been installed at the IGN switch short harness Pink connector(from under the dash), heading out to Ign Coil+. His TI Harness IGN feed wiring should have remained untouched. I think he's ok there. Since he's getting TI output 2.7v at Coil+ with IGN ON, it's telling me his coil voltage is within the 2.5v to 4.5v spec, just suspecting not enough crank voltage.

His only mod to the new Engine Harness was the Yellow Solenoid R wire. Normally a U-terminal(to Coil+), but with TI requires a blade type for the connection to the TI distributor PU Coil wiring plug(Pink).

Reference C3 photo from some previous posts....
img_3181_326fb1943de7ddeca203e3b364e0ca3b69e86692.jpg

img_5218_e7c4f7b2f2426838d611b33f22d9fa0f4270291f.jpg

[Peter S.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Terry,

Yes the C2 battery ground goes directly to a starter attachment bolt. Some exceptions for C60 & some BB equipped cars iirc.
Good to know about the separate engine ground at the pass side mount. Another place for corrosion the add crank resistance.

Peter,

Good you cleaned the paint from the metal areas. That may be a major contributor to the lower voltages.

As Gary mentioned, careful with the dielectric grease. Best to apply dielectric after fastener reattachment. This will keep moisture away from the bare metal. I never use it at the connection itself as it is an insulator.

I'd hold off on a starter change until you get results from your work.

Check back in when you get time. To reduce battery drain, maybe skip the voltage tests at first to see if it simply starts. If not, then I'd revisit the testing and check back in.

Rich
PS Glad your son's games were successful. Fun times.

Hi Rich - well no luck. I left the new starter in, and it did seem that I had a must stronger popping out the tail pipe, but still no ignition.

I have been using this on my electrical connections for the last decade, it is specifically for bimetallic connections and prohibits galvanic corrosion.
I have all but eliminated faulty grounds and other electrical gremlins which were typically encountered when sorting out a restoration.

[ATTACH=CONFIG]110649[/ATTACH]

I have kept up with this thread and I believe there is a mistake in the harness conversion.
What did you do with the original white covered coil wire in the repro harness?

Do you still have the complete original harness with which the engine ran correctly?

Hi James - yes, I do still have the original harness, but it has been clipped in a few locations. It was in tatters with some connections only held on with a few copper strands.

For the white covered coil wire, are you referring to this one pictured below (white w/ red and black) that was paired with the yellow R-solenoid wire? It is clipped w/ electrical tape on the end just hanging out.

[Michael B.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Just something additional to check. Are the wires at the two terminal connector from the distributor connected properly to the harness? You wouldn't think that the polarity of the pickup would matter but it did on my 69. I had similar symptoms, cranking with no fire and a sudden plug fire when I let the key return to RUN. The White and Green/White are marked differently so I assume the General wanted that pickup wired one specific way.

[Richard M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Hi Rich - well no luck. I left the new starter in, and it did seem that I had a must stronger popping out the tail pipe, but still no ignition.

Peter, Let's Step back a bit and plan on rechecking spark. Do you have a inductive timing light, or a series spark tester? We should also test the Crank voltages again at some point now that the battery is fully charged.

I'm confused a bit about the popping out the exhaust. Plug wires properly oriented? etc?

Are we certain we're getting fuel? Carb squirting at throttle blip?

When you get back to it, we can also do some telephone troubleshooting if you'd like. My #'s are in my profile. When we figure it out we can update info here eventually for future reference.

Just something additional to check. Are the wires at the two terminal connector from the distributor connected properly to the harness? You wouldn't think that the polarity of the pickup would matter but it did on my 69. I had similar symptoms, cranking with no fire and a sudden plug fire when I let the key return to RUN. The White and Green/White are marked differently so I assume the General wanted that pickup wired one specific way.

Michael, Yes that's a good point, but since he has the original distributor connector and TI harness connector, it shouldn't be different as he didn't have to touch those.

However, for reference, this is the proper polarity of that connector.....

White is closest to the plastic connector tab.
White is the input side of the PU Coil. i.e. the power input from IGN switch, via resistor wire in TI harness(or Solenoid R at Crank). This circuit also powers the TI Module. At Crank, Bat+ highest voltage goes to both PU Coil and Module, never directly to Ign Coil+ as in a points ignition.

Green/White(or solid Green if replacement) opposite side.
This is the output side of the PU Coil, to the TI module trigger input(Gray wire at dist connector).


(note this has a service replacement PU Coil(solid Green vs Green/White on originals)
PC230001.jpg

PC230012.jpg

Also for reference is the 1969 K66 B3 AIM page. See View A for the yellow wire modification. Also the note about removing the 12G Pink from the switch. This is that White-red/blk(resistor wire) & Yellow which normally goes to Coil+(points ign).
1969_K66_B3.jpg

[John M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Could the distributor be 180 off ? The initial post suggests the motor was rotated.

[Richard M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Could the distributor be 180 off ? The initial post suggests the motor was rotated.

John, Peter said he pulled the distributor, but only rotated the oil pump with a primer. As long as it went back in the same, should be ok.

But worth a check at #1 TDC to make sure distributor is properly configured, and the wires.

Rich

[Floyd B.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

James,

That's what I thought too. See my post #3 above. But Rich then gave me an education on TI, so I don't think that's the problem. If I understood him correctly, when the ignition switch is in the START position, the TI module acts as a relay and sends the voltage to the coil, so the resistor wire from the ignition switch to the coil isn't needed. In my case (non-TI), Bubba replaced the resistor wire with a common piece of wire he cut from his old tractor and added an external ballast resistor from an old refrigerator that he attached to the firewall with a drywall screw.

-Floyd-

[Peter S.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Peter, Let's Step back a bit and plan on rechecking spark. Do you have a inductive timing light, or a series spark tester? We should also test the Crank voltages again at some point now that the battery is fully charged.

I'm confused a bit about the popping out the exhaust. Plug wires properly oriented? etc?

Are we certain we're getting fuel? Carb squirting at throttle blip?

When you get back to it, we can also do some telephone troubleshooting if you'd like. My #'s are in my profile. When we figure it out we can update info here eventually for future reference.



Michael, Yes that's a good point, but since he has the original distributor connector and TI harness connector, it shouldn't be different as he didn't have to touch those.

However, for reference, this is the proper polarity of that connector.....

White is closest to the plastic connector tab.
White is the input side of the PU Coil. i.e. the power input from IGN switch, via resistor wire in TI harness(or Solenoid R at Crank). This circuit also powers the TI Module. At Crank, Bat+ highest voltage goes to both PU Coil and Module, never directly to Ign Coil+ as in a points ignition.

Green/White(or solid Green if replacement) opposite side.
This is the output side of the PU Coil, to the TI module trigger input(Gray wire at dist connector).


(note this has a service replacement PU Coil(solid Green vs Green/White on originals)
[ATTACH=CONFIG]110670[/ATTACH]

[ATTACH=CONFIG]110671[/ATTACH]

Also for reference is the 1969 K66 B3 AIM page. See View A for the yellow wire modification. Also the note about removing the 12G Pink from the switch. This is that White-red/blk(resistor wire) & Yellow which normally goes to Coil+(points ign).
[ATTACH=CONFIG]110672[/ATTACH]

Hi Rich,

Yes, I do have an inductive timing light, whatcha thinking?

I do have to take a pause for a bit as I don't have any time during the week and am out of town this upcoming weekend. I was concerned that perhaps I may have turned the distributor rotor when it was pulled, so I actually pulled a few spark plugs, reset the motor to TDC on compression at #1, reset the rotor to pointing at #1, reinstalled plugs and tried to fire again - no change.

[Richard M.]

Re: 1969 Engine Wiring Harness Replacement - will not fire

Hi Rich,

Yes, I do have an inductive timing light, whatcha thinking?

I do have to take a pause for a bit as I don't have any time during the week and am out of town this upcoming weekend. I was concerned that perhaps I may have turned the distributor rotor when it was pulled, so I actually pulled a few spark plugs, reset the motor to TDC on compression at #1, reset the rotor to pointing at #1, reinstalled plugs and tried to fire again - no change.

Peter, Just thinking it may be a good idea to go back to basics, start fresh and test for spark with the inductive timing light during Crank. Putting the inductance clamp on the coil wire would be best for continuous triggering visibility as opposed to a plug wire(one flash per dist rev).

Rethinking, I'm still a bit confused when you were getting clicking noises inside the distributor a while ago. Wondering now if it could've been spark arcing somewhere to ground or ?, like a bad cap or wire or corroded center contact to the rotor. Strange.

I understand this is part-time for you due to work responsibility and family stuff so when you get time give a yell and we'll revisit.

Rich