MainePorsche

I found this video in a prior thread (post #1). Maybe this will help with your question.

https://rennlist.com/forums/928-foru...l#post12100855

I don't have my documents with me, but I remember 4 or 4.2 bars being the 'zone'. Someone to confirm.

careful1

Maine, that video answers my first question. The modulator I replaced is the newer version and the one I purchased is the older style. So the plunger , I'm assuming ,won't work because it would need the cup looking plunger. I'm thinking that I will try to find an o-ring for it because the reason I replaced it in the first place was the leak it had. The old modulator actually worked fine....it just leaked.

SMTCapeCod

Looks like the one you removed might be missing the upper o-ring?

At any rate, might be interesting to know how long it lasted if you have record of its install. Also whether much adjustment is required to get the pressure into spec.

MainePorsche

No, don't throw out the baby with the bath water.
I remember about 2 years ago I replaced my modulator during a big transmission issue and the new 'old' style modulator worked with the new type thrust pin as seen in the video IIRC. I got it from Roger. I think there was some talk back then that some of the components were upgraded/changed. Take pics of the thrust pin and its seat in the base of the modulator, or do you see in your hand that it is a no go ?

careful1

I have the o-ring . It was just not in the photo.Is there more than one o-ring? I'm going to take it back out and post pictures of the new modulator and the plunger.

MainePorsche

Does the new modulator you're installing receive the cup type thrust pin, or does it accommodate the 'new' style thrust pin ?

careful1

The modulator has a flat metal surface. It looks like it needs the cup type because the plunger pin looks like the pin in the video with the pointed end ,a round flat part and the longer shaft that goes into the trans.

MainePorsche

Does that black plunger pin receiving piece come out of the old one (newer model), and can it be fitted into the new (old) modulator seat so it could accommodate the thrust pin ? Can that black piece be removed and act as a 'spacer' in the unit you plan to install ? Another thought, might you not want to get the cup plunger from one of our vendors or if you want to re-use the 'old' upgraded modulator, measure and get all new o-rings ?

careful1

I ordered a new one that should be here on Wednesday . I'll see how the new one works before I donate the "previous" new to anyone that might want it. Just so they realize it is the one with the black rubber cap without the thrust pin.

careful1

Well, I installed the modulator and the pressure measured 4.2 bars. The shifts are about as they were with the old modulator. My agenda was to stop the leaks and it appears to have worked . Too early to tell although. Sometimes it would take a week or so to start leaking, but it was definitely leaking at the modulator . Thanks for all the help I received from you guys. Also I have the old style modulator that I just bought that I will give to whoever wants or needs it.(free). Thanks, Doug.

careful1

Another view. It is new.

MainePorsche

Doug, you never described how you thought it mis-shifted.
Was it hard clunky shifts, or did you think the shifts were mis-timed (to early/to late from what you thought was right, or wanted) ?
This is important for you to sense and then described for the adjustments of each are different.

careful1

Maine, I originally just replaced it to stop the leak. But being a new modulator it needed to be adjusted. When I ordered the part I thought it would be what I already had on the car. The original modulator was a newer style and the plunger stem was not the correct one for the new part so I just bought a new one. My shifts seem to be smooth when shifting from drive through the gears. When it shifts into 1st it clunks. I'm not thinking it's too far off if any. But I need to drive it more to see. Is there a way to determine the perfect shift. I bought the gauge kit so I can connect to the port on the other side of the trans and drive with the gauge in the car. Don't know what to look for although.

MainePorsche

Doug,
Good Evening. I just got off duty, got my shoes off, and saw your post.
First what I would do is install the new modulator with its plunger. You are at 4.2 so you're in a good place. Make sure you have a good reliable vacuum line (and vacuum to it). Full ATF to between the MIN-MAX lines when hot at idle. Then drive it for a while, and then we'll go to shift timing adjustment and/or shift strength adjustment if needed (or not).
Craig

careful1

Thanks Craig, will do. I do need to check the level because of the leak. I know it is close but i want it right on. I have taken care of the vacuum leak a while ago by running a new hose from the engine compartment back to the modulator.