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Question About 722.120 Kickdown:
Quick question for those of you with experience with the 722.120 transmission. I'm pretty good with these units, but I do have an operating characteristic question for the forum at large.
When I rebuilt the engine in my 1879 300SD (116.120) I also rebuilt the transmission, replacing all of the bands, frictions, steels and bushings. There really wasn't anything wrong with it, I just thought it made sense to build it while I had everything out of the chassis. The only thing about this unit that puzzles me is how kickdown behaves below 50 mph. Above 50 mph, the unit downshifts a single speed range and accelerates strong all the way to about 80-85 mph when it upshifts into high speed range. However, if you mash the throttle below 50 mph, the unit downshifts two speed ranges and this results in engine rpm quickly reaching the governed limit and no increase in vehicle speed. If you keep your foot on the throttle, you can just hold the engine speed and vehicle speed constant. The unit will not upshift until you let up on the throttle. I have also checked all the requisite adjustments to ensure they are in accordance with the FSM. This isn't a big deal for me as I know just when and where the unit likes to upshift and downshift. I have also driven a few other similar 300SD's that all exhibited a similar characteristic. However, I recently drove an all original 1978 300SD that did not do this. Curiously, I examined the shift linkage on this car and found it to be no different than mine and all adjustments were similar in nature. Notwithstanding some internal changes, I was unable to find an externally recognizable reason for this. Any have a similar experience???...Robert Obviously, |
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Any similar experiences???
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Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
#3
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my 722.112 tranny will only kickdown 1 gear. I have never tried to kickdown above 50MPH.
Where did you get the new bands and friction discs steels and bushings from?
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1985 300TD Turbo Euro-wagon 1979 280CE 225,200 miles 1985 300D Turbo 264,000 miles 1976 240D 190,000 miles 1979 300TD 220,000 GONE but not forgotten 1976 300D 195,300 miles 1983 300D Turbo 175,000 miles http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg |
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Transmission Supply Center in Fresno, California...Robert
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Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
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Mine will downshift (1) speed range at any speed between 50 and 80 mph. Below 50 mph, I downshifts (2) speed ranges, maxes out the engine rpm and just hangs there until you let up on the throttle. Car has done this since I have owned it and I bought it from the original onwers.
I've adjusted all the linkage to specification. I just thought maybe I missed something...Robert
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Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
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Mine does that, I can get it to double-kickdown when going around 40-50mph....but it will quickly leave 2nd gear and go back to third if it goes into high rpms....it does not hold it until I let off....it does it on its own. Mine will readily kickdown 1 gear at pretty much any speed under 72mph.....
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-diesel is not just a fuel, its a way of life- '15 GLK250 Bluetec 118k - mine - (OC-123,800) '17 Metris(VITO!) - 37k - wifes (OC-41k) '09 Sprinter 3500 Winnebago View - 62k (OC - 67k) '13 ML350 Bluetec - 95k - dad's (OC-98k) '01 SL500 - 103k(km) - dad's (OC-110,000km) '16 E400 4matic Sedan - 148k - Brothers (OC-155k) |
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I may look into the adjustment on the detent linkage and back it off a bit, even though I set it to factory specificatiuon pursuant to the MBFSM...Robert
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Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
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I'm working on a turoial for the correct adjustment procedure.....
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Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
#9
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My 300E also does this, it will drop all the way to 1st if under 50mph during a hard kickdown but will immediately shift to 2nd. Its rather annoying.
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-diesel is not just a fuel, its a way of life- '15 GLK250 Bluetec 118k - mine - (OC-123,800) '17 Metris(VITO!) - 37k - wifes (OC-41k) '09 Sprinter 3500 Winnebago View - 62k (OC - 67k) '13 ML350 Bluetec - 95k - dad's (OC-98k) '01 SL500 - 103k(km) - dad's (OC-110,000km) '16 E400 4matic Sedan - 148k - Brothers (OC-155k) |
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The adjustment between the throttle rod and the kickdown switch is like a teeter-totter. I have been working with this and gaining ground on it. I will post in detail when I am done...:-)
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Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
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Doktor Bert - Have you completed this adjustment procedure? I have FSM to set linkages to spec but Bowden rod (not cable) to transmission hits a oil line that goes to turbo i believe. Not getting a double kickdown under 50 and seems a little sluggish...could not get above 50MPH on a 12% grade
I have the 1980 CA version of the 116
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1985 300D, 250k 1980 300SD, 180K |
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Update - Found linkage rod connecting to IP 10mm too long. Setting to spec helped....less pedal/better acceleration. Still can't always get double kick-down while under 50 even if i mash the pedal. Might still be the Bowden rod hitting the oil line at back of engine block. Happy with the current shift points.
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1985 300D, 250k 1980 300SD, 180K |
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Ok,
What I am wroking with at present is an intermittant 2-1 downshift on takeoff. As many of you know, the 722.120 with the 617.950 stays in 2nd speed range at a traffic light and downshifts to 1st speed range when you release the brake and apply throttle. I do know that there is a control unit in the RF passenger's footwell that wroks with the overboost protection circuit to influence transmisson downshift, but I am not sure if this is what controls the 2-1 downshift on takeoff. The 2-1 shift works fine most of the time, but then it will stop working for several days, then start working again. I have checked to see the connector on the electric valve is secure, so I am beginning to think this could be a bad solder joint in the control unit. Anyone have more experience with this system??? Thanks....Robert
__________________
Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
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I was under the impression from discussions on other threads that the 116 tranny didn't shift down to 1st then you release the brake and apply throttle, but when the car came to a complete stop, as if the mechanism was a pendulum which swung backward after a forward swing from braking. Perhaps I misunderstood what was happening. I know that on my 116, if I didn't come to a complete stop, it wouldn't downshift into 1st upon re-accelerating unless I hit the kickdown switch or manually moved the shift lever.
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1977 300d 70k--sold 08 1985 300TD 185k+ 1984 307d 126k--sold 8/03 1985 409d 65k--sold 06 1984 300SD 315k--daughter's car 1979 300SD 122k--sold 2/11 1999 Fuso FG Expedition Camper 1993 GMC Sierra 6.5 TD 4x4 1982 Bluebird Wanderlodge CAT 3208--Sold 2/13 |
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Quote:
Perhaps this is true????
__________________
Did you just pass my 740 at 200 kmh in a 300SD????? 1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013 100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership |
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