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  #1  
Old 06-09-2012, 09:59 PM
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bowden cable adjustment confusion

Hi folks,

chasing my 4500 rpm shift saga, I did some tests here is the data

when shifter in 3 pedal to the floor the engine pulls all the way to 5500 rpm and hangs on the governor - this is about 85 mph, no sputter no drama, an angry strong pull. btw OM606 sounds really mean at this rpm.

I reduce speed to 60 and shift to D, floor it, downshifts to 3 - goes till 70 mph in 3rd (exactly 4500 rpm) and shifts to 4.

I stopped and checked the cable adjustments, the FSM is quite cryptic in this - pull cable to feel slight resistance, adjust from sleeve and attach ball socket to ball head in this fashion.. PERFECT - I do that and the transmission cable runs out of length - meaning that the transmission cable is now stopping the accelerator linkage to go in full range, If I pull on the linkage the trans cable bracket starts to bend. back it off a little and I get early boggy shifts.

mechanics tell that the cable should be installed in a way that you pull it fully and adjust the adjuster in a way that at full accelerator the linkage lines up, I do that and I have extremely quick shifts - Im in third gear by 35 mph at more than half pedal, the transmission now shifts at 4000 rpm max..

How do you adjust this thing??

and when I pull the transmission cable, at the very end of travel it feels spongy - I have experience with jap cars and their kickdown cable positively stop against something - this one is kind of mushy..

This mechanic I consulted told me that maybe the speed governor pressure is too high causing the transmission to shift before redline, or the cable is wrongly installed in the trans,

The modulator is working because it holds vacuum and the way I have adjusted the bowden cable by feel I cannot even feel the shifts it glides.

Anyone with transmission experience please recommend something.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)
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  #2  
Old 06-10-2012, 01:16 AM
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Zulfigar:

If yhis was my car the first thing I would do is check the cable to make sure it's working right . That whole resistance at the ball annd socket is just a ball park thing as far as Ive found that cable will ajust with about half a turnand make a difference. the other thing is you said you have soft shifts this is a real no no in my opinion ajust the vacuum so you can feel the shift but not so it takes your head off. There are restricters you can make to cut down on the vaccuum. When you get it dialed in with the vacuum then start ajusting the cable. The vacuum effects the whole trans the softer the shift the more slippage (shorter life) good luck!!!
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  #3  
Old 06-10-2012, 03:57 PM
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I think a pan drop is in order to check the bowden cable installation and then a complete trans pressure check.

The car drives really nice but when I want it to run it falls short because the engine really pulls hard beyond 4000 rpm. Anyone here to tell me what exactly I should be seeing, by the book there is a rod that the cable attaches to in the trans - is there some gotcha while installation that can cause lack of cable travel.
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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)
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Old 06-12-2012, 03:37 AM
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From the way you describe the cable restricting your throttle movement when set as the FMS says, makes me wonder about the linkage lengths, would be worth checking them over


when you unsnap the ball and pull on the cable by hand, can you feel slight tension against the end,,,,,it's supposed to be pulling a lever that presses a plunger

I have same rapid upshift symptom, regardless of cable adjustment so it seems

The mechanic who changed it was right about it being disconnected but now that it IS connected and I still have the rapid upshift symptom, ATSG points to the governor pressure being too high

I posted the other day asking about how to check that pressure, I dk if it's even possible


This weekend I'm going to go over everything again from linkage to modulator pressure and vac, see what I can see
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1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
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  #5  
Old 06-12-2012, 10:08 AM
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The 95 E300D linkage is extremely simple, it only has one rod with ball sockets connecting to the pump, movement is relayed from the pedal via cable and an arm translates pull motion to downward push motion to the pump lever, the transmission cable is connected to the piece that pulls. There is only one adjustment of the linkage and Ive done it, the adjustment is to remove all freeplay when the linkage is pulled by the pedal.
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1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)
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Old 06-12-2012, 01:01 PM
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One of my cars is a '90 300D that came with the same 722.4 trans. Since I bought it, I could never seem to get the trans to reliably kick-down under all circumstances. I tried futzing with the cable, swapping the kick-down switch, and yet nothing could resolve the problem. I got to the point of manually downshifting when the situation called for it. Very frustrating.

A few months back the trans just stopped shifting reliably--would upshift in rapid sequence--so I opted to swap in a known good 722.3 from a 603. Now, when I punch it, the kick-down engages right away like it should. Mind you, I re-used the exact same .4 kick-down cable, so I strongly suspect that this item is a red herring with regard to the OP's trans issues.
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Old 06-12-2012, 01:23 PM
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Quote:
Originally Posted by SpecialDelivery View Post
From the way you describe the cable restricting your throttle movement when set as the FMS says, makes me wonder about the linkage lengths, would be worth checking them over


when you unsnap the ball and pull on the cable by hand, can you feel slight tension against the end,,,,,it's supposed to be pulling a lever that presses a plunger

I have same rapid upshift symptom, regardless of cable adjustment so it seems

The mechanic who changed it was right about it being disconnected but now that it IS connected and I still have the rapid upshift symptom, ATSG points to the governor pressure being too high

I posted the other day asking about how to check that pressure, I dk if it's even possible


This weekend I'm going to go over everything again from linkage to modulator pressure and vac, see what I can see
checking is possible, the port is on the same side of the transmission that has the bowden cable, the test pressures are about 1/2 to 3/4 driving speed in mph.

meaning 30 mph would be between 15 and 20 psi. I dont get how the governor can fail with increased pressure, I have seen the exact opposite, I have seen a governor gear completely sheared off, but that was a toyota RWD auto.
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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)
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Old 06-12-2012, 01:33 PM
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verrry interesting, thank you for sharing Zuli, keep us posted! If your cable is unhooked in the transmission ( no resistance on pulling it at all) The plastic retainer clip at the end cracked, then hopefully the issues would be clarified by a new cable

Get some good strong magnets (the ones from computer hard drives are really strong and flat) please let us know what you find when you open the pan!! Take pictures!!
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1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)
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Old 06-12-2012, 11:58 PM
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sure will, as soon as I get some days off, ive been working straight for a month now, no breaks no weekends, so the MB gets attention usually at the side of the road with a flashlight or if Im really a good boy I get off early about an hour before sundown..

btw - its comical that 99% of times my name has been mangled up on this board, I dont take offence because its not an english name to come by..

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1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)
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