Weird spark advance problem...

[Bort62]

Alright, so I figured out that you really DO need to remove the resistor wire when upgrading to DSII.

The voltage drop was causing my GM module to flake out at low RPM. Duh.

Anyway, that allowed me to get my idle down to about 750 rpm. I went to set the advance again since I had the idle speed right, and I noticed that it was up around 35* initial. (Was at 10* initial before resistor wire removal).

So, problem is - I dropped the initial down to 10* again and everything is fine, but...

when I rev - it shows my mech advance coming in and RETARDING the timing 10*. Just about 2 hours earlier (before removing the resistor wire) I had double-checked it and it was working exactly as it should.

So what the hell? How can my spark timing retard w/ RPM ? I only have mechanical + initial, no vac. Mech is limited to 10* via welding the plate in the dist.

Anyone seen this before or am I just seeing things?

 

[addo]

What if you swap polarity of the coil wires into the module?

 

[fordconvert]

Im thinking polarity of the module also. Orange & Purple wires need swapped. When its wrong it fires somewhere between the points depending on speed.

 

[Bort62]

Alright, Since I trust you guys - I switched polarity. Seems to run better now which is weird because I drove it all last spring the previous way...

I re-set the timing to 10* initial, and it stays there... but when I rev, I don't get any advance. It just stays at 10*...

Last night, this was all working perfectly. 10* initial at idle and 20* total. I then ran a true 12v line to my coil+module, and I turned the idle down to 750. Magically, all sorts of problems.

Suggestions as to why I am not getting my mech advance? Dist seems to move freely and spring back like it should. Possibility of too light a spring or something causing it to come ALL in at such a low RPM ?

 

[addo]

That sounds likely to me, since you've passed it on the "tweak" test for sticky advance.

 

[Bort62]

So why was it working yesterday?

 

[Bort62]

It really doesn't seem like the springs are too light... it feels normal and I find it hard to believe that my advance is all in my 750 rpm...

 

[fordconvert]

Here is the 'right' way as far as the orange/ purple wires on the module.

I think there are or were some sites that had it wrong, I thought they were all updated but maybe there are some links still out there. There is also one version where the way I read the text I get it wrong but the picture is right then if you re read the text you get it right.

For checking the mechanical advance you have the vacuum unhooked and plugged right? When you do have the vac hooked up is it on SCV, ported, or manifold?

 

[Bort62]

Vac unhooked. I haven't even started messing with that yet...

Setup is a Carter YF on a 200, DS II.

 

[66 Fastback]

I would think it unlikely that all the advance is in at 750 rpm too. I've got no DSII experience but if you were getting erratic readings with the polarity crossed, could it be that the advence you were getting before these changes was coincidental and may have been in error? Just wondering if the advance might be binding or not getting any movement of the weights and plate. Although it is a pain to remove the plates, you might try either removing a spring to see if that changes the advance and brings it in earlier.
Doug