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Won't start after distributer spring change.
https://www.slantsix.org/forum/viewtopic.php?t=36781		 Page 1 of 1
Author:  wjajr [ Tue Aug 18, 2009 1:43 pm ]
Post subject:  Won't start after distributer spring change.
Some of you have been following my "Still screwing around with the Holley 390" thread here in "Engins" where Aggressive Ted and others have been holding my hand during a re curve. I installed the new spring (Silver) popped the distributor back in, and fired her up. Started instantaneously, but was running a bit ragged as I missed by one tooth to the plus side. It has happened before, and will happen again... So I turned it back a tooth, and it started right up. Now, for some reason the bolt that secures the distributor was not in the same relative position as before this project. I again pulled the distributor set to a different tooth , and now the engine won't fire. I have had this distributor in and out many times before with no problem.

Amongst all the confusion I lost track of which way I had been switching to a new tooth set. Long story short, yanked the valve cover, rolled the engine over until # 1 intake opened & closed to a point that both intake & exhaust were unloaded At this point I'm figuring that # 1 is at TDC, the timing mark was at TDC, and lined up rotor button with # 1 plug wire. Cranked it over, one cylinder fired once than nothing but cranking. While I crank, the timing light will blink on, but no start, so there is voltage on the high side.

Checked the ballast resistor; getting 2 to 3 ohms, 12 V one side, 6 volts or so other side, and swapped it out just to make sure that was not the problem Getting 6 volts or so at coil, and 12 + volts at the usual locations.

Pulled the distributor once again reset the reluctor to pick-up gap; at .007". Put it all back together, one cylinder fired than just cranking.

I did gently pinch the pigtail from the pick-up under the distributor clamp early in this ordeal, but that device is showing about 240 ohms, so I think is has continuity.

What am I missing here??? Bad coil? not sure how to test it. Wrong synchronization of distributor?
Author:  Aggressive Ted [ Tue Aug 18, 2009 2:37 pm ]
Post subject: 
wjajr,

I think your on the right track......that ohm rating is a little low and the output may not be enough to trigger the box. You may have pinched the pig tail too hard. I have done it....I know. I have had intermittent pops where one cylinder will fire and thats it, just one. Then wait awhile re-spin for another single pop......

Take your ohm meter with you to the Auto Parts and test the PU's before you buy them. My good ones have been 390 ohms or more. Some of the new ones are wound with wire as fine as your hair.......skip the cheap $12- $14 dollar ones and spend the $30 or so for a good one.

A test to try: if the distributor was in a vise to where you could spin it while reading the voltage at the pigtail, you should see about 1/2 of a volt or more. I know it's hard to do but is a good functional test.....you may or may not be successful seeing anything depending on the quality of your meter. The digital ones may show a reading better than the old analog units.

I hope this helps....
Author:  64'4$peed [ Tue Aug 18, 2009 3:06 pm ]
Post subject: 
you could be a 180 degrees off on the distributor. although it sounds like you had it lined up right. I've had an orange box go out on me and do the same thing. you might need a new ecu. or swap to HEI.
Author:  wjajr [ Tue Aug 18, 2009 5:34 pm ]
Post subject: 
Ted:
Quote:
I think your on the right track......that ohm rating is a little low and the output may not be enough to trigger the box. You may have pinched the pig tail too hard. I have done it....I know. I have had intermittent pops where one cylinder will fire and thats it, just one. Then wait awhile re-spin for another single pop......
Bingo!

Now that I think back a few days, idle quality has been slipping a bit since the pinch, that happened during the last a spring adjustment, a rather intermittent skip over and above the lope beat.

How dose one test the orange box aside from touching the silver disk, and grounding the other hand? Not a lot of test info in my 1967 FM covering ECU & pointless distributors... LOL

My meter is digital, something we had to build for an electronics course I took a while back, and it use to agree with another digital VOM which I can't seem to find these days.

So its off to NAPA tomorrow if I can't spin a half volt out of her.
Author:  wjajr [ Wed Aug 19, 2009 7:26 am ]
Post subject: 
I replaced the pickup, still no start. Is there a testing procedure for an orange ECU?
Author:  1969ronnie [ Wed Aug 19, 2009 10:02 am ]
Post subject: 
does that reluctor have 2 slots and is it installed in the same slot as before the spring swap? ronnie
Author:  Aggressive Ted [ Wed Aug 19, 2009 12:09 pm ]
Post subject:  Trouble shooting the ECU
wjajr,

You might re-tighten the bolts holding the ECU in place. The ECU needs to be well grounded for it to work well and last. I actually run an extra ground wire to it so there are no ECU burn out issues or intermittent idle problems.

I do not have a schematic on the internals, so I am not sure what the values should be at the (4) pins other than seeing 6 - 8 volts at pin 1. Pin 2 is the output to the coil which (usually 6-8 volts depending on the which ballast resistor your using) and Pins 4 & 5 to the pick-up. Pin 3 is not used on the new ECU's.

If you have a spare ECU in your glove box, now is the time to dust it off.

What is the ohm rating of your new pickup?
Author:  wjajr [ Wed Aug 19, 2009 3:07 pm ]
Post subject: 
Quote:
What is the ohm rating of your new pickup?
365 ohms
Quote:
If you have a spare ECU in your glove box, now is the time to dust it off.
Only have the one ECU. I have a diagram of which lead goes where.
Quote:
You might re-tighten the bolts holding the ECU in place. The ECU needs to be well grounded for it to work well and last.
I had that thing off this spring, and made sure to ground it well. Maybe I'll run a ground loop over to it, won't hurt.

Just to go over the four cycle engine timing of #1 one more time. Exhaust valve closes than intake opens than closes some where near TDC on end of compression stroke, right? At the end of that intake closing event #1 should be firing at that point, and rotor button should be at plug wire #1....

I keep going over this because I must be missing something.

Second thought: If my ignition system was firing plugs properly, and engine not timed correctly there should be some pops & farts during cranking. Right?
Author:  64'4$peed [ Wed Aug 19, 2009 3:19 pm ]
Post subject: 
Are you getting spark from all the wires? I'd buy a spark tester instead of grounding a plug. If not I'd say bad ECU. HEI swap! cheaper and more reliable
Author:  wjajr [ Thu Aug 20, 2009 11:57 am ]
Post subject: 
Installed a grounding loop to the old orange box. Still no start. So, I guess a new ECU is need. See my "Orange Box" thread over on "Electrical " board about this, as we have moved away from mechanical engine stuff at this point.
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