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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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JeffBowlsby
post May 8 2025, 10:15 PM
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Another documented case of a completely fractured MPS diaphragm holding at least some vacuum. Amazing that it holds any vacuum at all, which affects the inductance values of the internal coils and ultimately injector pulse width.
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