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> Stumbling 1974 2.0...It's finally fixed. Post 63., Thanks to everyone who weighed in, embarrassing reason posted below...
orthobiz
post Sep 13 2019, 06:15 PM
Post #41


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So I did more checking according to the Ignitor II instruction sheet.

Checked the air gap, it's just under 0.020" and has not changed.
The net resistance of the aluminum Ignitor plate to ground is less than 0.2 ohms.
The voltage test shows 9+ volts, which is more than 8.0V.

All meeting spec.

So, other electrical issues could be...?
What's with the 123 Distributor?

Paul
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rjames
post Sep 13 2019, 11:17 PM
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QUOTE(orthobiz @ Sep 13 2019, 05:15 PM) *

So I did more checking according to the Ignitor II instruction sheet.

Checked the air gap, it's just under 0.020" and has not changed.
The net resistance of the aluminum Ignitor plate to ground is less than 0.2 ohms.
The voltage test shows 9+ volts, which is more than 8.0V.

All meeting spec.

So, other electrical issues could be...?
What's with the 123 Distributor?

Paul


123 distributor is plug and play. Easy setup. Love mine so far.
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rjames
post Sep 13 2019, 11:18 PM
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QUOTE(orthobiz @ Sep 13 2019, 05:15 PM) *

So I did more checking according to the Ignitor II instruction sheet.

Checked the air gap, it's just under 0.020" and has not changed.
The net resistance of the aluminum Ignitor plate to ground is less than 0.2 ohms.
The voltage test shows 9+ volts, which is more than 8.0V.

All meeting spec.

So, other electrical issues could be...?
What's with the 123 Distributor?

Paul


123 distributor is plug and play. Easy setup. Love mine so far.
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orthobiz
post Sep 14 2019, 12:25 PM
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Updated post #1.

Paul
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mepstein
post Sep 14 2019, 01:13 PM
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Time for the six conversion (IMG:style_emoticons/default/happy11.gif)
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orthobiz
post Sep 15 2019, 07:05 PM
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Looking to test MPS according to my post #1. Set the vacuum at 10 for five minutes, held the negative pressure just fine. Now want to check the leads.

"If the vacuum test is passed, check the coil resistances. The primary coil is measured between terminals 7 and 15 and should measure about 90 ohms. The secondary coil is measured between terminals 8 and 10 and should measure about 350 ohms"

Are these numbered on the MPS? Do I take it out of the car? Is there a diagram of the terminals??

Paul
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JeffBowlsby
post Sep 15 2019, 07:54 PM
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Vacuum pump test at 15 in. Hg.

Ohm test inner and outer pairs of terminals (its two coils)

Good vacuum and coil tests would be encouraging, but its the calibration that determines the A/F ratio. Has your MPS been previously adjusted?
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orthobiz
post Sep 15 2019, 08:14 PM
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No previous adjustments...will test tomorrow, thanks Jeff. Will redo the vacuum test but I think it will pass.

Paul
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rjames
post Sep 15 2019, 09:41 PM
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QUOTE(JeffBowlsby @ Sep 15 2019, 06:54 PM) *

Vacuum pump test at 15 in. Hg.

Ohm test inner and outer pairs of terminals (its two coils)

Good vacuum and coil tests would be encouraging, but its the calibration that determines the A/F ratio. Has your MPS been previously adjusted?


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This is key.
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914werke
post Sep 15 2019, 11:49 PM
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if it still has the epoxy filled over it nose ..it hasnt
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JeffBowlsby
post Sep 16 2019, 05:08 PM
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To be sure, it also needs the four aluminum rivets in place, to know it has not been previously opened.
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orthobiz
post Sep 16 2019, 08:15 PM
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I took the MPS out. Could they make ANYTHING on this engine that is easy to get to??

Anyway, there is no epoxy plug. So the unit has been opened.

The outer leads have 94 ohms resistance and the inner two have...
0.362 ohms! Like "no ohms."

This must mean something, right?? Does leaving the ignition on do this?? I'm beginning to think my LED light installation is unrelated to what's going on.


Paul
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orthobiz
post Sep 16 2019, 08:17 PM
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orthobiz
post Sep 16 2019, 08:47 PM
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Also, it has passed the 15 inch Hg test without any problem, maybe down to 14 after 5 minutes.

Do you have one Jeff??

Paul
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JeffBowlsby
post Sep 16 2019, 09:05 PM
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For 0.362 ohms...sure your DVM was not set to the 1K scale?

I have an 043 core I would need to build before I can offer it. Let me do that this weekend and get back to you if interested. I usually only rebuild folks' original MPS cores.

Someone has been in that MPS in the last few years, I do recognize the Tangerine WOT stop (allen key), but not the red thread lock drop.
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rjames
post Sep 17 2019, 12:46 AM
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You will need an 02 sensor to tune it properly, so prep for that.
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orthobiz
post Sep 17 2019, 03:23 AM
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Actually it is set to KOhm on the meter, but the other reading is 94 also on the same setting...I figured it would read 364 since it goes to 4 digits on the scale? It only has one setting for resistance. So maybe it is OK??

Paul

QUOTE(JeffBowlsby @ Sep 16 2019, 11:05 PM) *

For 0.362 ohms...sure your DVM was not set to the 1K scale?

I have an 043 core I would need to build before I can offer it. Let me do that this weekend and get back to you if interested. I usually only rebuild folks' original MPS cores.

Someone has been in that MPS in the last few years, I do recognize the Tangerine WOT stop (allen key), but not the red thread lock drop.
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orthobiz
post Sep 17 2019, 07:11 AM
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It's embarrassing...

My Micronta Radio Shack digital meter has the Ohm symbol visible when it's a low number, like 94 for one set of leads. Then the symbol disappears so the 0.364 number really is 364 ohms.

I guess the MPS checks out grossly: good vacuum and good resistances. I think adjusting AFM and 02 sensors may be way above my comprehension level!

Paul
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ChrisFoley
post Sep 17 2019, 08:37 AM
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Two suggestions: Pull the injectors and spray carb cleaner (thru a tube) into the back end to flush any debris that might be clogging their inlet screens.
Then consider making a small adjustment to the MPS to add slight enrichment. Knowing who rebuilt the unit and what if any changes they made could be very helpful.
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orthobiz
post Sep 17 2019, 11:38 AM
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Thanks Chris. Am considering all options!

Paul
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