MPS, Rebuilding the MPS Options

[Ron914]

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 .

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 .

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 .

[Superhawk996]

Good job and report out on the testing Ron. (IMG:style_emoticons/default/aktion035.gif)

I don’t like the disconnected correlations between Dakota, IR temp, and the oil temperature gauges. Something seems off to me. Especially if the engine was started cold at ambient and only run 15 minutes idling before pictures of gauges were taken.

At the moment - let’s not get pulled down the rabbit hole of trying to figure out why these temperatures don’t seem well correlated. We very well may have to come back to this later.

I especially don’t like that you are saying you’re reading less than 50 ohms of CHT temp resistance on the currently installed CHT when head is supposedly only 140ish and the engine stalls.

Are you measuring the head (aluminum) that is exposed? Sorry to ask stupid question but need to ensure 140F isn’t the temp of the engine tin. As another plausibility check, a bare hand can lightly touch or quickly tap /touch 140F surface for a second or two without feeling like you’re going to get burned. Does this seem right? (Do not burn yourself - just trying to establish that we are talking about a touchable part of the head not being nearly as hot as boiling water).

The bench testing of the new CHT seems plausible both ambient at 212ish.

Swap the CHT sensor and see what happens.

[Ron914]

Good job and report out on the testing Ron. (IMG:style_emoticons/default/aktion035.gif)

I don’t like the disconnected correlations between Dakota, IR temp, and the oil temperature gauges. Something seems off to me. Especially if the engine was started cold at ambient and only run 15 minutes idling before pictures of gauges were taken.

At the moment - let’s not get pulled down the rabbit hole of trying to figure out why these temperatures don’t seem well correlated. We very well may have to come back to this later.

I especially don’t like that you are saying you’re reading less than 50 ohms of CHT temp resistance on the currently installed CHT when head is supposedly only 140ish and the engine stalls.

Are you measuring the head (aluminum) that is exposed? Sorry to ask stupid question but need to ensure 140F isn’t the temp of the engine tin. As another plausibility check, a bare hand can lightly touch or quickly tap /touch 140F surface for a second or two without feeling like you’re going to get burned. Does this seem right? (Do not burn yourself - just trying to establish that we are talking about a touchable part of the head not being nearly as hot as boiling water).

The bench testing of the new CHT seems plausible both ambient at 212ish.

Swap the CHT sensor and see what happens.

Good morning ,
I have a small job to help a friend today so it will be afternoon before I get back to this and I need to buy a 13 mm socket and make a relief in the 3" extension first . I shot my IR at the stud that the intake runner bolts to and also was under the car and shot the exposed head ,I think the runner bolt where it attaches to the head should be a good place . I will follow up later this late afternoon when I return . I agree and will replace the CHT sensor once I get the paper tool for removal and report findings