Starting Issues, '83 SC No Spark

[NoYouRelax]

I just completed an engine drop to replace the clutch and now I am having starting issues. I complete the CDI troubleshooting and proved out voltages. I also proved that I have voltage from the coil to the center of the coil to the center of the dizzy. To prove this, I set the coil lead near a ground and watched it arc momentarily

I replaced all the plug wires during this engine drop and the ignition rotor. I check the resistance in the rotor and oddly it is hard to get a steady resistance reading if at all. Could the rotor be defective right off the shelf? I can get an instaneous resistance reading sometimes, but is very sporadic. Has anyone seen anything like this?

If the rotor is an unlikely culprit, what else should I try? How can I prove out the pulse circuit attached to the dizzy (that green lead with a shield). I check it for VAC but pulsing was not consistant.

[Scott R]

It seems like every time this topic comes up it's the plug wire order thats wrong. The main issue being that the SC distributor turns counter-clockwise.

[Joe Bob]

Yup, Bentley has it wrong......

So no spark at the plugs? Tried grounding? Tried a shot of ether into the intake? Lifted the flapper inside the air box to listen for the fuel pimp? CD box whines?

[NoYouRelax]

I watched the rotation of the distributor, counter clockwise, and layed out the wires in firing order, accordingly.

- I have fuel to the injectors
- Ran fuel pump and lifted flapper momentarily to hear flow
- CDI box does whine
- Grounded a spare plug externally to visually confirm no spark
- Set center wire (from coil to distrubter) close to ground to confirm arcing...per Haynes

My testing meter shows an instantaneous resistance across the rotor, but then reads open circuit. Of course, I tossed the old rotor and have nothing to compare it too.

[kodioneill]

Transposed reference and crank position wires/plugs?

[schumicat]

there are none on SC.

search here for green distributor wire.

QUOTE=kodioneill;7332225]Transposed reference and crank position wires/plugs?[/QUOTE]

[NoYouRelax]

Just checked rotor again and its fine. I had meter on too low of a setting. It reads 4.7 Ohms.

[boyt911sc]

Bill,

Determine why there is no ignition spark. This is an electrical problem and need to sort it out systematically. Put everything on hold and focus only on locating the culprit for this 'no spark' problem. Without this ignition spark present, the engine is not going any where. Sit back and relax, and review what could have been over looked. This is one reason I delay the replacement of ignition parts (CDI, distributor, spark plug cables, etc.) during an engine rebuild or an engine drop. It complicates the problem solving by adding more variables in the equation.

Do you still have the old spark plug cables? Did you work on the ignition distributor by any chance? Keep us posted.

Tony

[schumicat]

if you've already done the green wire troubleshooting as I suggested earlier, try pulling and cleaning the contacts in the 14 pin harness.

[NoYouRelax]

Well I got it running after deciding to put the new wires back to the same position where the original ones were found.

Before I started into the clutch work I marked all the spark plug sires and their positions on the distributor. I found the #4 wire where the #1 wire should be for true TDC. This is 180 degrees out from conventional but it works, and again as found prior to my work.

I am guessing that the PO did some distributor work to make it fire this way. If anyone knows why this might be, please share.

The engine runs fine, but now I am working on a few idle issues.

Thanks again for all the insight, guidance and support.

Bill

[Joe Bob]

Ummmm, the dizzy was inserted 180 degrees backwards and he compensated but reversing the plug wires? Dunno if that is possible......but look into it based on your description.

[theiceman]

i would suggest taking the cap off and have some one turn the starter so you can see it spin. i think there is a notch on the dist housing for cyl one..

[NoYouRelax]

The dizzy is bolted in in only one possible position. I used the dizzy notch for TDC when I did the valve job. Normally the #1 wire is positioned just over the dizzy bolt, slightly to the left.

Very puzzling, but a timing light will show me more.

One other telltale was that the dizzy cap was previously installed 180 degrees out by PO. There is a notch to set it in one position, but the PO had the cap latched onwithout the notch setting in its place.

Its hard to believe the engine runs this way, but I marked alll the wires, the front of the cap and positions on the cap as I disassemble things.

[NoYouRelax]

I am no mechanic by any means, just a curious engineer with lots of tools, but the PO or his wrench left me with a few laughs.

I have learned to just walk away and come back with a fresh look later or as Tony says....get a beer and relax!!!

Cheers!

[NoYouRelax]

Originally Posted by Joe Bob

Ummmm, the dizzy was inserted 180 degrees backwards and he compensated but reversing the plug wires? Dunno if that is possible......but look into it based on your description.

Correction, and agreed Joe Bob.....I can now see/visualize how the dizzy was installed 180 degrees out by PO. It seems like a matter of removing the dizzy, and rotating the shaft 180 and reinstalling it, followed by rotating the wire positions on the cap accordingly. Either way, I need to get back to the true TDC position and points of reference for future work.

I would love to the rates charged by the PO's wrench......some of the findings are bizarre and it makes me wonder whats lingering.

The devil you know is better than the devil you don't know!

Thanks all,

Bill

[Scott R]

Why bother with any of that? Just get #1 to the top of the compression stroke and drop the dizzy back in. No need to try and correct someones bad work, just do it right from the start.

[NoYouRelax]

Distributor orientation corrected by partial removal of dizzy and turning rotor 180 degrees. Wires repositioned 180 degrees as well. TDC is really TDC and coincides with the dizzy pointing to notch and number 1 wire. Timing was reset too.....

Now continuing chasing the high idle issue(s)

[Joe Bob]

So....my guess was right? Cool if it was.....seen that happen back in the day with VWs....

[NoYouRelax]

Originally Posted by Joe Bob

So....my guess was right? Cool if it was.....seen that happen back in the day with VWs....

Joe- Bob was right, I had to back off and think about it, but forgot to grab a Guiness.

Next task...fix my high idle issue. Idles nice at 800 rpm, but like to climb to 2300 rpm when warmed and driving around.

[Joe Bob]

Great....gonna email this thread link to my ex wife.....according to her and her lawyer....I'm never right....

If it's running....go out and drive the hell outta it.