[250 Al head] Ongoing ignition trouble (long)

that's some good info, bubba
 
@WSA111,

Thank you for tip on the MSD coil wire! I've searched for a way to buy just a high quality coil wire without success. I thought I had searched Summit but apparently not.

The Accel spark plug wire kit I picked up at OReilly included angled boots, but the wide part of those angled boots was too wide for the coil terminal on my distributor cap; luckily, I still had the angle boot from the old coil wire. The coil wire I made is not ideal, but will work until I receive the MSD coil wire I ordered today.

Unfortunately, the engine still won't start - no spark. There's a test for the MSD, which I intend to perform today. Either:

* The magnetic pickup isn't switching the MSD correctly; or
* The large red wire to the MSD isn't receiving full voltage; or
* The MSD itself isn't working properly

Thanks,
Bob
 
You can test the MSD, by taking the unused white wire & grounding it should produce a multiple spark. If not the box may be defective.
If you want to ditch the box i sell a HEI module which can be hooked up to your DS11 to the MSD adapter.
But you need a good 12V source to the coil which hooks up to the HEI module. I would rather have the MSD, but this a second choice. Bill
 
Update:

I pulled the large connector off of the MSD 6-AL and checked the pins connected to the small red wire (ignition switched) and large red wire (battery constant) with a multimeter - both seemed OK (small red wire had voltage only when the ignition was on; large red wire always had voltage).

Following MSD's troubleshooting directions, I disconnected the MSD from the magnetic pickup, jumpered two of the three pins on the magnetic pickup connector (orange and brown or green wires, not the black wire), then removed the jumper, expecting to see a spark from the coil output wire, which was grounded. Did see a spark just twice, then could not get any more sparks.

I THINK this means that the coil is OK (otherwise, I wouldn't get any sparks at all), but something is wrong with the MSD unit - this is rank speculation, but maybe there's a bad capacitor that slowly charges, so that I can get one or two sparks, then it's discharged and I can't get any more sparks.

Plan to call MSD tech support.

Thanks
Bob
 
Bob, MSD is now owned by Holley. They at one time would refurbish customers boxes. Let us know what the deal is.
Take a look at my HEI module deal. I have 1 left see my ad in the small six parts for sale. Questions just give me a shout. Bill
 
Happy Halloween!

Received my MSD coil wire kit (with female to male coil tower conversion - thank you @WSA111!) today and plan to install that today, but I don't expect that to solve my ignition failure as I think I have more issues besides.

It turns out I bought the MSD 6-AL in August 2015, so it's out of warranty (one year).

I called MSD anyway to see if I could get any information. MSD technical support claims that it's impossible for the unit to fail in such a way that it can produce a spark initially and not later. They suggested that the voltage may be falling on the trigger (small red) wire. I doubt this, but I ordered a terminal block that I can use (instead of a splice) to connect the trigger wire to the MSD. Once connected through the terminal block, I can put a multimeter on the terminal block and monitor the voltage from the trigger wire as I crank the engine or test the MSD with the jumper wire on the magnetic pickup connector. I plan to connect the battery power (large red wire) through the terminal block also (the terminals are isolated, not on a common bus). Using this method, I can verify that the trigger wire and battery wire are maintaining close to 12 volts as I crank the engine or test the MSD with the jumper wire on the magnetic pickup connector.



If I don't find any voltage drop, I may call MSD again but it's probably time to replace the MSD.

Thanks
Bob
 
Greetings Ford Six Fans,

Made great progress on the Ranchero while watching the HOUSTON ASTROS (my hometown team) win the world series!

It seems that the inability to start was caused by:

* Bad ignition switch wiring (replaced the connector and wiring)
* Corroded terminal on coil wire (replaced the coil wire with an excellent MSD specialty coil wire)
* A loose connection from the battery to the MSD 6-AL (large red wire)

This last one was strange:

I have a terminal block below my battery; I like this better than having several connections hanging off of my + battery terminal. The loose connection was the one from the + battery terminal to the terminal block. With the engine off and the alternator supplying no power, the loose connection was supplying all the power to gauge lights, tachometer, oxygen sensor, stereo, etc., and all of these things seemed to work continuously. Can only surmise that, because the MSD operates at the millisecond level, even a very slightly loose connection can cause it to misfire. Cleaned the copper lug and wing nut with a wire brush and tightened the connection, and she started immediately! Of course, at that point I had already replaced the ignition switch wiring and the coil wire. The magnetic pickup and coil were also replaced in the process; let's consider that a tune-up. When I started troubleshooting, did not realize that the ignition setup in the Ranchero was two years old (although, with only 2,000-3,000 miles).

Back to the issue that caused me to originally create this post - after replacing the ignition switch wiring, replacing the coil wire and fixing the loose connection, the Ranchero started very easily and idled well, but wouldn't rev without backfiring. This time I realized that this only happened if the vacuum advance cannister was connected to vacuum. I disconnected the cannister and was then able to rev the engine without the backfire. The Ranchero will now start very easily and idles well, but doesn't rev as easily as before, and runs very lean (15.5 - 18) at part throttle acceleration and cruise. Was able to drive it around the block, but I'm worried about the lean condition, and it's not running as well as it should.

I did re-check the initial timing (was probably at 24 degrees, backed it down to 20), set the idle mixture (idles at 12.5 - 14.5 now), and set the idle speed. If driven very conservatively, building RPMs gradually, the Ranchero runs well enough to drive it a few miles, maybe to a car show or cruise-in. The accelerator pump on the carburetor is definitely working - I can see the jet of gas when I work the throttle. The main circuit/jets must be working or I wouldn't be able to rev the engine up to 3,000 RPM.

Since the engine backfires if attempting to rev with the vacuum cannister connected, there must be some issue with the distributor. I did verify that the vacuum advance cannister moves if vacuum is applied (tested this with a Mighty Vac). Holding a timing light on the engine while revving it, the timing does generally advance, so the mechanical advance must be working, at least to some degree. The timing isn't "going crazy" (moving all over the place) as I was told it would if the polarity was reversed on the magnetic pickup.

Thanks,
Bob
 
If you have the initial set to 20* what is the total timing on this engine?

Is the advance plate messing with the internal wiring of the distributor? What is the AFR when the car is backfiring?

All of this points to the module imho or a problem with the distributor. Maybe put an ohm meter on the pickup leads and advance the distributor all the way back and forth with your vacuum pump and see if there is an internal break in the wires that is opening up or shorting as the advance plate moves. Repeat with the meter connected to the dist plugs ground wire and the engine block or a known good ground. I'd leave the distributor assembled while you do this. If that all checks out OK, try a different module. It's easy enough to hook up a DSII box just to test and see if it will rev fine with a DSII box. Buy and return it or keep it as a spare.
 
Seth, just sent another DS11 distributor to Bob to install & eliminate the distributor question. He is going to send the present one in the engine back to me for testing. We will go from there.
In the end it will be something minor that is causing a major problem.
Will know next week.
 
Greeting Ford Six Fans,

I swapped out the distributor for one provided by @WSA111 and the engine seems to run perfectly, although I did not have time to take her out for a test drive. The engine revs well, including with vacuum advance connected.

Comparing the old distributor to the new, I realized that the reluctor on the old one wasn't fully seated down on the shaft and was about .10" high (not perfectly lined up with the magnet on th pickup). Could that cause the difficulty revving?

I should be able to test drive later this week.

Thanks,
Bob
 
Since last Saturday (11/18) was the last local car show (Niftee 50ees) until spring, I cleaned up the Ranchero and drove it to the car show (a 30 mile round trip).

The Ranchero ran great as long as I didn't thrash it. If I ran it at WOT, ran it up to about 5,000 RPM and shifted at that RPM, the engine died shortly after the shift. I'm convinced that the engine is dying because of the MSD male coil adapter - it doesn't fit into the Accel Super Coil female socket tightly enough (even after I modified it slightly in an effort to make it fit more tightly). When the car died, if I pressed the male coil adapter back into the female socket, the Ranchero would start.

I plan to order a <= 0.7 Ohm e-core coil ("TFI" type) with a male coil wire connector. Then I won't need the MSD male coil adapter.

Thanks
Bob
 
:beer: congrats Bob sounds like you close to getting it fixed. Good luck (y) :nod:
 
After the issue I had about two weeks ago with the Ranchero dying if thrashed, and thinking this was due to the MSD male terminal adapter, I had resolved to get a coil with built-in male terminal.

Although initially focused on the MSD Blaster SS (an e-core type):

https://www.summitracing.com/parts/msd-8207/overview/

I found a cannister type coil at Summit Racing with a built-in male terminal: the MSD Blaster 3:

https://www.summitracing.com/parts/msd-8223/overview/

I think I'll try this one, since it would allow me to use my existing coil mount while providing the built-in male terminal I need.

Thank you,
Bob
 
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