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  #1  
Old 03-04-2013, 04:31 PM
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can you spot the vaccum regulator in this pics? 722.3 auto tranny.

I have a euro w123 300turbodiesel with a 722.3 tranny. the former owner had some sort of idea that the tranny would withstand more if it shifted really hard between gears. I was hoping to adjust the vacuum so that the tranny would shift normally. found some pictures of this modul regulator, but i cant find it on my tranny. took some pics (pardon the quality)
Can any of you point out where i can make these adjustments, or at least try to explain where to look?

Any help is appretiated.
Cheers
Attached Thumbnails
can you spot the vaccum regulator in this pics? 722.3 auto tranny.-2013-03-03-14.52.31.jpg  
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  #2  
Old 03-04-2013, 05:33 PM
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What year is your car? Earlier models used control rods instead of a vacuum modulator.
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2003 Volvo V70 5 Speed
1997 E290 Turbo Diesel Wagon -traded for above, an amazingly comfortable car to drive, great drivetrain, but the rust, oh my god the rust
1992 BMW 525i -traded in
1990 Silver 300TE -Sold Loved the wagon, hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold
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  #3  
Old 03-05-2013, 06:31 AM
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The vacuum modulator is on the other side.

It is #60 in the picture below:



Adjusting should be done with a pressure gauge attached and at a certain speed:



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  #4  
Old 03-06-2013, 04:29 PM
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It's a car with a 1980 body, but no one knows for sure what year the engine and tranny is. from what i gather its atleast an '82.
And for Govert; could you be a bit more specific please?
How do you adjust it, and what do i look for in the gauge? you say its attached at a certain speed, do i need to be driving to get the readings i need?
Cheers
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  #5  
Old 03-06-2013, 07:57 PM
BB-Lou-KY
 
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vacuum regulator adjustment

When I adjusted mine (first time) it was a bit confusing, not having done it before, but it's fairly simple. Pop off the little black rubber cap, (mine split, new one cost about $3.00) and there's a small metal "key" nestled in a plastic setting that looks like a castellated nut, like where you would usually find a cotter pin. Pull it out, careful, it moves easily, or at least mine did. A magnetic tip screwdriver was very helpful, in such a tight space. The advice I was given was turn it clockwise to firm up shifts, counter-clockwise to soften them up. Turn a few notches, keep track, don't go too much at once, 3-5 is enough. Cap it up, drive it and see what, if any difference you feel. Further adjustments based on that. Don't forget to check the kick down cable, from throttle linkage on top of engine. I found my plastic adjustment nut broken, so put in a spacer to closely match my other 300TD (which runs great), wired that test assembly in place, and it made the biggest improvement in how it runs and shifts. Now maybe someday I'll actually replace the cable. Good Luck! Enjoy the bonding time!
Bob
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  #6  
Old 03-07-2013, 02:39 AM
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I am assuming that you have a 722.315 euro transmission.

You attach a pressure gauge to the port next to the modulator. Disconnect the vacuum line. Drive around in D at 50 km/h (30 mph). Pressure should be 2.9 bar. If not, take off cap of the modulator and turn up or down (to the right is more pressure). 360 turn of the key is 0.4 bar adjustment.

If you don't have a gauge or if it is too much trouble, you can also use the method described by Bob. Adjust until the shifts at partial load are neither harsh nor slipping.

The vacuum system must hold vacuum, so replace the rubber socks, threeways, fourways and the cap of the modulator if suspect.

Last edited by Govert; 03-07-2013 at 05:20 AM.
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  #7  
Old 03-07-2013, 05:03 AM
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722303

Quote:
Originally Posted by Govert View Post
I am assuming that you have a 722.315 euro transmission.
thanks Govert,very useful data,.

are those the same for .303 tranny?


cheers
ChO

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Old 03-07-2013, 05:44 PM
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Quote:
Originally Posted by cho View Post
thanks Govert,very useful data,.

are those the same for .303 tranny?
The modulator pressure for a 722.303 (North American) transmission from 1981 through 1984 should also be 2.9 bar according to the FSM. The 1985 has a modulator pressure of 3.3 bar.
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  #9  
Old 03-12-2013, 12:38 PM
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Update on my tranny worries!

So I found the vaccum modulator, thanks to you guys!
And I now see why its shifting so roughly; the vaccum modulator is not connected to anything.
the hose/line/pipe (pardon the language barrier) is completely missing.
So I do have a new question for you, where is it suppose to go? To me it would make sense to try and connect it so that the pressure would be following the throttle. the engine was replaced once, and there are alot of loose ends around.
I figured it'd had to be this one, sitting on the right side of the dieselpump.

Is this where to connect?
Thanks for your help so far

PS: I do believe its a 772.315 euro tranny.
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can you spot the vaccum regulator in this pics? 722.3 auto tranny.-2013-03-10-13.45ring.jpg  
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  #10  
Old 03-12-2013, 03:59 PM
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The part circled doesn't look like any modulator I've ever seen... It looks more like a drain tube.... Isn't that box the neutral safety switch?
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2003 Volvo V70 5 Speed
1997 E290 Turbo Diesel Wagon -traded for above, an amazingly comfortable car to drive, great drivetrain, but the rust, oh my god the rust
1992 BMW 525i -traded in
1990 Silver 300TE -Sold Loved the wagon, hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold
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  #11  
Old 03-12-2013, 05:09 PM
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Quote:
Originally Posted by plainoldtrygve View Post
So I found the vaccum modulator, thanks to you guys!
And I now see why its shifting so roughly; the vaccum modulator is not connected to anything.
the hose/line/pipe (pardon the language barrier) is completely missing.
So I do have a new question for you, where is it suppose to go? To me it would make sense to try and connect it so that the pressure would be following the throttle. the engine was replaced once, and there are alot of loose ends around.
I figured it'd had to be this one, sitting on the right side of the dieselpump.

Is this where to connect?
Thanks for your help so far

PS: I do believe its a 772.315 euro tranny.
The picture is of a vacuum control valve (VCV). The thing in the red line is the vent line. It should have a vacuum line connected to it that ends in the interior, where it can suck clean air.
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  #12  
Old 03-12-2013, 05:13 PM
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I believe that's the Vacuum Control Valve he has in the picture.
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  #13  
Old 03-14-2013, 03:29 PM
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I'll try to be more specific.
Found the vaccum modulator, but there is no line connected to it.
I want to reconnect it, but where to? Where does the line go to, from the vacuum modulator on the gearbox?
I just thought it might be the thing circled in red on my previous post.

Thanks again, people
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  #14  
Old 03-14-2013, 03:40 PM
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You found the vacuum modulator on the side of the transmission and there is no vacuum line going to it?

Well - that would certainly cause hard shifting for sure.
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  #15  
Old 03-14-2013, 04:15 PM
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Quote:
Originally Posted by Govert View Post
The modulator pressure for a 722.303 (North American) transmission from 1981 through 1984 should also be 2.9 bar according to the FSM. The 1985 has a modulator pressure of 3.3 bar.
thank you G!

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next wish/project: w114 coupe OM603 powered
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