Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

4 Pages V < 1 2 3 4 >  
Reply to this topicStart new topic
> 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


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



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
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rjames
post Sep 13 2019, 11:17 PM
Post #42


I'm made of metal
****

Group: Members
Posts: 3,908
Joined: 24-July 05
From: Shoreline, WA
Member No.: 4,467
Region Association: Pacific Northwest



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.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
rjames
post Sep 13 2019, 11:18 PM
Post #43


I'm made of metal
****

Group: Members
Posts: 3,908
Joined: 24-July 05
From: Shoreline, WA
Member No.: 4,467
Region Association: Pacific Northwest



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.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 14 2019, 12:25 PM
Post #44


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



Updated post #1.

Paul
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
mepstein
post Sep 14 2019, 01:13 PM
Post #45


914-6 GT in waiting
***************

Group: Members
Posts: 19,213
Joined: 19-September 09
From: Landenberg, PA/Wilmington, DE
Member No.: 10,825
Region Association: MidAtlantic Region



Time for the six conversion (IMG:style_emoticons/default/happy11.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 15 2019, 07:05 PM
Post #46


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



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
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
JeffBowlsby
post Sep 15 2019, 07:54 PM
Post #47


914 Wiring Harnesses
*****

Group: Members
Posts: 8,462
Joined: 7-January 03
From: San Ramon CA
Member No.: 104
Region Association: None



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?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 15 2019, 08:14 PM
Post #48


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



No previous adjustments...will test tomorrow, thanks Jeff. Will redo the vacuum test but I think it will pass.

Paul
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rjames
post Sep 15 2019, 09:41 PM
Post #49


I'm made of metal
****

Group: Members
Posts: 3,908
Joined: 24-July 05
From: Shoreline, WA
Member No.: 4,467
Region Association: Pacific Northwest



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?


(IMG:style_emoticons/default/agree.gif)

This is key.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
914werke
post Sep 15 2019, 11:49 PM
Post #50


"I got blisters on me fingers"
*****

Group: Members
Posts: 9,988
Joined: 22-March 03
From: USofA
Member No.: 453
Region Association: Pacific Northwest



if it still has the epoxy filled over it nose ..it hasnt
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
JeffBowlsby
post Sep 16 2019, 05:08 PM
Post #51


914 Wiring Harnesses
*****

Group: Members
Posts: 8,462
Joined: 7-January 03
From: San Ramon CA
Member No.: 104
Region Association: None



To be sure, it also needs the four aluminum rivets in place, to know it has not been previously opened.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 16 2019, 08:15 PM
Post #52


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



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
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 16 2019, 08:17 PM
Post #53


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



(IMG:http://www.914world.com/bbs2/uploads_offsite/live.staticflickr.com-7438-1568686620.1.jpg)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 16 2019, 08:47 PM
Post #54


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



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
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
JeffBowlsby
post Sep 16 2019, 09:05 PM
Post #55


914 Wiring Harnesses
*****

Group: Members
Posts: 8,462
Joined: 7-January 03
From: San Ramon CA
Member No.: 104
Region Association: None



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.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rjames
post Sep 17 2019, 12:46 AM
Post #56


I'm made of metal
****

Group: Members
Posts: 3,908
Joined: 24-July 05
From: Shoreline, WA
Member No.: 4,467
Region Association: Pacific Northwest



You will need an 02 sensor to tune it properly, so prep for that.
User is online!Profile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 17 2019, 03:23 AM
Post #57


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



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.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 17 2019, 07:11 AM
Post #58


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



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
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
ChrisFoley
post Sep 17 2019, 08:37 AM
Post #59


I am Tangerine Racing
*****

Group: Members
Posts: 7,906
Joined: 29-January 03
From: Bolton, CT
Member No.: 209
Region Association: None



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.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
orthobiz
post Sep 17 2019, 11:38 AM
Post #60


Senior Member
***

Group: Members
Posts: 1,754
Joined: 8-January 07
From: Cadillac, Michigan
Member No.: 7,438
Region Association: Upper MidWest



Thanks Chris. Am considering all options!

Paul
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

4 Pages V < 1 2 3 4 >
Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 



- Lo-Fi Version Time is now: 16th April 2024 - 01:17 AM