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> MPS, Rebuilding the MPS
Ron914
post May 8 2025, 05:06 PM
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Hello to all who have helped me with this project . @emerygt350 ,@TJB/914, @Superhawk996 , @ChrisFoley , @rjames , @MDTerp
I am in the middle of rebuilding my MPS and have a couple of comments and questions .
First when I opened up the unit I found the most difficult job was removing the rivets holding the two halves together.
When I removed the retainer plate to take out the old diaphragm it was in two pieces .
Attached Image
I needed to take two measurements since I was replacing the stop screw , I needed to measure the the stop screw protrusion into the housing . The instruction sheet sent to me by a member had the measurements he must have made when rebuilding his MPS . His stop screw protrusion was 1.97mm and mine only measured 1.72mm.
His inner/outer screw assembly depth in the old diaphragm measured 6.51mm .
Here's one of my questions ?
when I measured mine I got two measurements depth to inner/outer screw assembly was 4.03
and depth to the washer outside the inner/outer screw assembly was 5.46mm.
Again there is a difference and since mine was never accessed before (epoxy over screw was not disturbed) is the difference in measurements ok and which measurement should I use I will try to attach a photo or two to help with my question.
this one .
Attached Image
I have not touched either of these measurements yet and awaiting any help/comments.
I think it's this one to the washer on diaphragm .
Attached Image
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emerygt350
post May 14 2025, 12:29 PM
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Although no leak is best. That leak is pretty slow so if it can't get any better I bet you will be fine.
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Ron914   MPS   May 8 2025, 05:06 PM
Superhawk996   There you have it, now you know why it was a leake...   May 8 2025, 06:36 PM
Ron914   There you have it, now you know why it was a leak...   May 8 2025, 06:58 PM
MDTerp   There you have it, now you know why it was a leak...   May 8 2025, 08:17 PM
Ron914   Well all done . I must say it was easier than I th...   May 8 2025, 08:30 PM
JeffBowlsby   Another documented case of a completely fractured ...   May 8 2025, 10:15 PM
emerygt350   Way to go. I mean you are disassembling the most ...   May 9 2025, 06:57 AM
rjames   Crazy that it could hold vacuum at all!   May 9 2025, 10:01 AM
Superhawk996   Crazy that it could hold vacuum at all! Mine...   May 9 2025, 01:24 PM
Ron914   Well I was optimistic that my car was going to run...   May 9 2025, 05:37 PM
emerygt350   You can pull the wires one at a time till you find...   May 9 2025, 06:09 PM
Superhawk996   This is going to be a tough love post. When you ...   May 9 2025, 07:26 PM
Ron914   This is going to be a tough love post. When you...   May 12 2025, 03:17 PM
Superhawk996   I’m going to post this over here This is anoth...   May 9 2025, 07:53 PM
rjames   What Hawk said. And you just rebuilt your MPS, so...   May 9 2025, 08:17 PM
Ron914   Thank you Superhawk and emery ,You are correct in...   May 9 2025, 08:27 PM
emerygt350   Once it is all back together, remember that inner ...   May 10 2025, 04:22 AM
emerygt350   Don't worry about TDC, the distributor only go...   May 12 2025, 05:50 PM
Ron914   Don't worry about TDC, the distributor only g...   May 12 2025, 06:57 PM
fiacra   If only I didn't live in California I would b...   May 12 2025, 08:03 PM
Ron914   If only I didn't live in California I would ...   May 12 2025, 09:46 PM
Superhawk996   First on the to do list MPS is leaking down too ...   May 12 2025, 06:57 PM
Ron914   First on the to do list MPS is leaking down too...   May 12 2025, 09:44 PM
Superhawk996   Aren’t other guys in CA running 123’s? Regard...   May 12 2025, 07:00 PM
Superhawk996   Also with respect to the dizzy vs timing Yes - s...   May 12 2025, 07:19 PM
Ron914   As far as putting a 123 in my California car I was...   May 12 2025, 09:11 PM
Superhawk996   I would open the MPS back up. I can post time lap...   May 13 2025, 08:37 AM
Ron914   I would open the MPS back up. I can post time la...   May 13 2025, 10:19 AM
emerygt350   I agree with hawk. The first time I rebuilt mine ...   May 13 2025, 10:02 AM
fiacra   Ron got that Pertronix from me, and yes it is olde...   May 13 2025, 01:34 PM
Ron914   Ron got that Pertronix from me, and yes it is old...   May 13 2025, 03:25 PM
fiacra   If I was to eventually pass a smog test I could t...   May 13 2025, 07:00 PM
Superhawk996   Remote stater switch is about $15 and pricele...   May 13 2025, 01:35 PM
Superhawk996   Z0n2aTFRMiI?si=W8rg02X2Kwp4r_54 I cut this off at...   May 13 2025, 02:40 PM
rjames   There is an art (and likely some luck) in getting ...   May 13 2025, 03:00 PM
Ron914   There is an art (and likely some luck) in getting...   May 13 2025, 03:10 PM
SVG223   Good luck with this, my MPS is leaking too, watchi...   May 13 2025, 04:18 PM
Ron914   [quote name='SVG223' post='3205335...   May 13 2025, 09:01 PM
JeffBowlsby   Just a heads up, there are other places the MPS ca...   May 13 2025, 06:18 PM
JeffBowlsby   dbl dbl.   May 13 2025, 06:18 PM
Ron914   Well I opened my MPS and found that the order in w...   May 14 2025, 07:57 AM
ChrisFoley   I switched from a round o-ring to square in my kit...   May 14 2025, 10:45 AM
Ron914   I switched from a round o-ring to square in my ki...   May 14 2025, 12:07 PM
emerygt350   I think that is exactly what I did the first time ...   May 14 2025, 11:54 AM
Ron914   I think that is exactly what I did the first time...   May 14 2025, 12:08 PM
Ron914   I think that is exactly what I did the first time...   May 14 2025, 04:36 PM
emerygt350   I think that is exactly what I did the first tim...   May 14 2025, 04:48 PM
emerygt350   Although no leak is best. That leak is pretty slow...   May 14 2025, 12:29 PM
Superhawk996   Get rid of the adapters Go straight from vacuum ...   May 14 2025, 01:41 PM
Ron914   Get rid of the adapters Go straight from vacuum...   May 14 2025, 04:32 PM
Superhawk996   [quote name='Superhawk996' post='3205480' date='M...   May 14 2025, 05:58 PM
rjames   [quote name='Superhawk996' post='3205480' date='...   May 14 2025, 06:20 PM
Ron914   [quote name='Superhawk996' post='3205480' date='...   May 15 2025, 12:29 PM
SVG223   Mine takes 45 seconds to leak from 10 in/hg to 5 i...   May 14 2025, 03:12 PM
emerygt350   Mine takes 45 seconds to leak from 10 in/hg to 5 ...   May 14 2025, 04:18 PM
ChrisFoley   Problem with the old square o-ring is that it will...   May 15 2025, 08:57 AM
Ron914   Problem with the old square o-ring is that it wil...   May 18 2025, 01:41 PM
Superhawk996   :trophy: you’re getting there!   May 18 2025, 02:17 PM
rjames   No need to crack it open again to adjust if you ha...   May 18 2025, 03:12 PM
Ron914   Well after putting the old square O ring back in ...   May 24 2025, 08:40 AM
rjames   Put the ecu knob back in the middle and adjust onl...   May 24 2025, 09:16 AM
Ron914   Put the ecu knob back in the middle and adjust on...   May 24 2025, 10:27 AM
rjames   Put the ecu knob back in the middle and adjust o...   May 27 2025, 06:30 PM
Superhawk996   I need to add that I must set my timing still , ...   May 28 2025, 05:36 AM
Ron914   I need to add that I must set my timing still ,...   May 29 2025, 06:25 PM
JeffBowlsby   Of those three pairs of wires, one is grounds for ...   May 24 2025, 10:49 AM
Ron914   Of those three pairs of wires, 1 iz grounds did t...   May 24 2025, 11:09 AM
Superhawk996   Those grounds are mighty crispy and corroded and a...   May 28 2025, 05:31 AM
Superhawk996   My bad Ron I completely forgot you were running P...   May 30 2025, 04:15 AM


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