Re: [MBZ] 603 VCV swap cures hard shifting
Everything I've seen lists the transmission modulator pressure at a given speed, implying the car is moving. I've found that, at least for the 722.315 in most of the early 80's turbos, that the pressure in motion is within about 0.1 bar of the pressure at idle. What I do is get the transmission good and warm (at least 20 minutes of driving), run the car up on the ramps, set the modulator pressure, and then take her for a test drive while still observing the pressures. It may or may not require another quarter turn or so to nail it perfectly. I happen to have a rather crude gauge sitting in the garage that anyone is welcome to borrow for the cost of shipping. Gary Thompson Georgetown, TX 1995 E320 On 6/7/07, Alex Chamberlain [EMAIL PROTECTED] wrote: Is that measured with or without the vacuum line hooked up? The article on mbz.org suggests without, but I'm unclear whether that is when the car is stationary (presumably idling), while in motion, or both.
Re: [MBZ] 603 VCV swap cures hard shifting
--- Alex Chamberlain [EMAIL PROTECTED] wrote: Is that measured with or without the vacuum line hooked up? The article on mbz.org suggests without, but I'm unclear whether that is when the car is stationary (presumably idling), while in motion, or both. 1.) Without 2.) Both Poos Moody friends. Drama queens. Your life? Nope! - their life, your story. Play Sims Stories at Yahoo! Games. http://sims.yahoo.com/
Re: [MBZ] 603 VCV swap cures hard shifting
--- Loren Faeth [EMAIL PROTECTED] wrote: 123.123.12 Probably a 722.116, based on the information you gave me. 2.8 bar. position D, 65 km/h 4.8 (+/-0.2) bar, position D, stationary All measurements at operating temperature with vacuum line disconnected. Poos Need a vacation? Get great deals to amazing places on Yahoo! Travel. http://travel.yahoo.com/
Re: [MBZ] 603 VCV swap cures hard shifting
Yes, the thing on the transmission is the modulator. The blue flying saucer is a vacuum amplifier, that just acts to smooth out the vacuum source going to the transmission. The only real easy test for the modulator is to pull a vacuum on it and verify it holds. You can affect the firmness of shifts by adjusting the modulator. There's a little T handle under a dust cover (usually black rubber on older models, green plastic on newer ones). Some people do it by feel, but I strongly recommend putting a guage on the transmission modulator pressure access port and adjusting it to spec. Don't know off the top of my head what the spec is for that tramnsmission is, but it's probably somewhere in the neighborhood of 2.8-3.0 bar. Someone with a TDM will have to look it up. Gary Thompson 1995 E320 On 6/6/07, Alex Chamberlain [EMAIL PROTECTED] wrote: Update: I found a couple of leaks where I expected them to be (between the vacuum pump and vacuum control valve) and corrected them. ACC works now. The new VCV and old modulator (blue flying saucer) are performing to spec---sending 17 in. of vacuum to the trans at idle. But shifts are still clunky! I haven't got under the car yet. What's at the other end of the black vacuum line from the flying saucer to the transmission? Rusty's site shows an AT Modulator Valve that looks like it has a vacuum connection on one side. Is this what I'm looking for? How do I test it? I couldn't find anything about it in the W124 FSM, but there's not much there on transmissions. If it does need to be changed, is it going to be messy? Should I drain the tranny first? Help! My brief taste of correct Mercedes transmission operation was like a drug---I want more. Alex Chamberlain '87 300D Turbo '93 Isuzu Trooper '86 Lincoln Mark VII LSC
Re: [MBZ] 603 VCV swap cures hard shifting
On 6/7/07, Gary Thompson [EMAIL PROTECTED] wrote: Yes, the thing on the transmission is the modulator. The blue flying saucer is a vacuum amplifier, that just acts to smooth out the vacuum source going to the transmission. The only real easy test for the modulator is to pull a vacuum on it and verify it holds. You can affect the firmness of shifts by adjusting the modulator. There's a little T handle under a dust cover (usually black rubber on older models, green plastic on newer ones). Some people do it by feel, but I strongly recommend putting a guage on the transmission modulator pressure access port and adjusting it to spec. Don't know off the top of my head what the spec is for that tramnsmission is, but it's probably somewhere in the neighborhood of 2.8-3.0 bar. Someone with a TDM will have to look it up. OK, so forgive my slowness...as I understand it the plan of attack should be: 1. Put Mityvac on modulator, if it holds vacuum, it just needs to be adjusted. I take it the modulator takes a fixed pressure setting and combines it with the vacuum on the input to decide shift firmness, correct? So I can just set it at warm idle and forget it? I see what could be the removable cover you're talking about next to the vacuum nipple in Rusty's picture. Will any kind of pressure gauge do or is this something I need a special tool for? 2. Alternately if modulator doesn't hold vacuum it will need to be replaced... again, is this something I need to drain the trans first to do? How is the modulator RRed? It seems like if it goes into the side of the trans it should screw in (sort of like the temp sensors in the head) but Rusty's picture doesn't show anything that looks like either threads or flats for a wrench. Thanks much, Alex Chamberlain '87 300D Turbo '93 Isuzu Trooper '86 Lincoln Mark VII LSC
Re: [MBZ] 603 VCV swap cures hard shifting
Alex, Go check out my tranny adjuting article written many moons ago at http://articles.mbz.org/transmission/adjust/ No, you don't have to drain the tranny to RR the modulator. And it is held in on these cars through the use of a thrust plate, that is, a small metal plate that is clamped to the side of the tranny that fits in a slot in the side of the modulator. You take off the plate and the modulator pulls right out. Replacement can be tricky, since you have to be careful not to pinch the O ring on the neck of the modulator. Give me a transmission model number and I can look up the vacuum value in the TDM. Poos --- Alex Chamberlain [EMAIL PROTECTED] wrote: On 6/7/07, Gary Thompson [EMAIL PROTECTED] wrote: Yes, the thing on the transmission is the modulator. The blue flying saucer is a vacuum amplifier, that just acts to smooth out the vacuum source going to the transmission. The only real easy test for the modulator is to pull a vacuum on it and verify it holds. You can affect the firmness of shifts by adjusting the modulator. There's a little T handle under a dust cover (usually black rubber on older models, green plastic on newer ones). Some people do it by feel, but I strongly recommend putting a guage on the transmission modulator pressure access port and adjusting it to spec. Don't know off the top of my head what the spec is for that tramnsmission is, but it's probably somewhere in the neighborhood of 2.8-3.0 bar. Someone with a TDM will have to look it up. OK, so forgive my slowness...as I understand it the plan of attack should be: 1. Put Mityvac on modulator, if it holds vacuum, it just needs to be adjusted. I take it the modulator takes a fixed pressure setting and combines it with the vacuum on the input to decide shift firmness, correct? So I can just set it at warm idle and forget it? I see what could be the removable cover you're talking about next to the vacuum nipple in Rusty's picture. Will any kind of pressure gauge do or is this something I need a special tool for? 2. Alternately if modulator doesn't hold vacuum it will need to be replaced... again, is this something I need to drain the trans first to do? How is the modulator RRed? It seems like if it goes into the side of the trans it should screw in (sort of like the temp sensors in the head) but Rusty's picture doesn't show anything that looks like either threads or flats for a wrench. Thanks much, Alex Chamberlain '87 300D Turbo '93 Isuzu Trooper '86 Lincoln Mark VII LSC ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Sucker-punch spam with award-winning protection. Try the free Yahoo! Mail Beta. http://advision.webevents.yahoo.com/mailbeta/features_spam.html
Re: [MBZ] 603 VCV swap cures hard shifting
On 6/7/07, LWB250 [EMAIL PROTECTED] wrote: Go check out my tranny adjuting article written many moons ago at http://articles.mbz.org/transmission/adjust/ Thanks, that is exactly what I needed to know! Give me a transmission model number and I can look up the vacuum value in the TDM. 722.416 (in an '87 300D Turbo). Where can I get a pressure gauge that will work (or the parts to build one as mentioned in the article)? I don't have any spare fuel injection parts lying around, unfortunately. (Nor easy access to a U-Pull-It full of 123 diesels like some people on the list...) Thanks much for the help! Alex Chamberlain [EMAIL PROTECTED]
Re: [MBZ] 603 VCV swap cures hard shifting
--- Alex Chamberlain [EMAIL PROTECTED] wrote: 722.416 (in an '87 300D Turbo). Modulator pressure (bar) 3.0, position D @ 50km/h Working pressure (bar) 14.1, position D stationary Poos Be a better Globetrotter. Get better travel answers from someone who knows. Yahoo! Answers - Check it out. http://answers.yahoo.com/dir/?link=listsid=396545469
Re: [MBZ] 603 VCV swap cures hard shifting
Could you tell me the values for an 81 240D. At 04:36 PM 6/7/2007, you wrote: --- Alex Chamberlain [EMAIL PROTECTED] wrote: 722.416 (in an '87 300D Turbo). Modulator pressure (bar) 3.0, position D @ 50km/h Working pressure (bar) 14.1, position D stationary Poos Be a better Globetrotter. Get better travel answers from someone who knows. Yahoo! Answers - Check it out. http://answers.yahoo.com/dir/?link=listsid=396545469 ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Loren Faeth
Re: [MBZ] 603 VCV swap cures hard shifting
Sure, but I either need a chassis number (123.xxx) or transmission number 7xx.xxx). Poos --- Loren Faeth [EMAIL PROTECTED] wrote: Could you tell me the values for an 81 240D. At 04:36 PM 6/7/2007, you wrote: --- Alex Chamberlain [EMAIL PROTECTED] wrote: 722.416 (in an '87 300D Turbo). Modulator pressure (bar) 3.0, position D @ 50km/h Working pressure (bar) 14.1, position D stationary Poos Be a better Globetrotter. Get better travel answers from someone who knows. Yahoo! Answers - Check it out. http://answers.yahoo.com/dir/?link=listsid=396545469 ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Loren Faeth ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mailp=graduation+giftscs=bz
Re: [MBZ] 603 VCV swap cures hard shifting
On 6/7/07, LWB250 [EMAIL PROTECTED] wrote: 722.416 (in an '87 300D Turbo). Modulator pressure (bar) 3.0, position D @ 50km/h Working pressure (bar) 14.1, position D stationary Is that measured with or without the vacuum line hooked up? The article on mbz.org suggests without, but I'm unclear whether that is when the car is stationary (presumably idling), while in motion, or both. Alex
Re: [MBZ] 603 VCV swap cures hard shifting
123.123.12 I can look up the trans number somewhere if you need it. This is the one year without a mechanical linkage between the throttle and the trans. Thanks Loren At 04:53 PM 6/7/2007, you wrote: Sure, but I either need a chassis number (123.xxx) or transmission number 7xx.xxx). Poos --- Loren Faeth [EMAIL PROTECTED] wrote: Could you tell me the values for an 81 240D. At 04:36 PM 6/7/2007, you wrote: --- Alex Chamberlain [EMAIL PROTECTED] wrote: 722.416 (in an '87 300D Turbo). Modulator pressure (bar) 3.0, position D @ 50km/h Working pressure (bar) 14.1, position D stationary Poos ___ _ Be a better Globetrotter. Get better travel answers from someone who knows. Yahoo! Answers - Check it out. http://answers.yahoo.com/dir/?link=listsid=396545469 ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Loren Faeth ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mailp=graduation+giftscs=bz ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com Loren Faeth
Re: [MBZ] 603 VCV swap cures hard shifting
On 6/4/07, Alex Chamberlain [EMAIL PROTECTED] wrote: At some point during the trip I sprung a major vacuum leak---the center air vent snapped shut and now doesn't open regardless of ACC setting, and all shifts went back to the previous state of CLUNKiness regardless of throttle position. A quick look under the hood didn't show any obvious disconnections or other open points in the circuit, so I imagine I stressed one or more of the lines and cracked it/them while manhandling things to get the old parts out and new ones in. Update: I found a couple of leaks where I expected them to be (between the vacuum pump and vacuum control valve) and corrected them. ACC works now. The new VCV and old modulator (blue flying saucer) are performing to spec---sending 17 in. of vacuum to the trans at idle. But shifts are still clunky! I haven't got under the car yet. What's at the other end of the black vacuum line from the flying saucer to the transmission? Rusty's site shows an AT Modulator Valve that looks like it has a vacuum connection on one side. Is this what I'm looking for? How do I test it? I couldn't find anything about it in the W124 FSM, but there's not much there on transmissions. If it does need to be changed, is it going to be messy? Should I drain the tranny first? Help! My brief taste of correct Mercedes transmission operation was like a drug---I want more. Alex Chamberlain '87 300D Turbo '93 Isuzu Trooper '86 Lincoln Mark VII LSC
[MBZ] 603 VCV swap cures hard shifting
I had a satisfying car-repair weekend. As long as I've had my 300D it's shifted hard, especially at light throttle. Downshifts were especially bad: the typical suburban driving maneuver of rolling up to a red light at 5 mph, then accelerating as it turns green to 30 mph or so, was accompanied by a soundtrack of WHAM from the rear end on the 2-1 downshift and smaller bangs on the 1-2 and 2-3 shifts. Shifting into reverse at idle produced a cringeworthy CLUNK that made me envision gear-teeth inside the differential snapping off like icicles on a sunny day. I'd assumed that the tranny was just old, and that changing the fluid frequently would be the only thing that would help it until such time as it failed completely and would be replaced or rebuilt. (And Mobil 1 did seem to help a little.) Then I read some posts on the mbshop.com forums about vacuum control adjustments, and decided to test the vacuum control valve (the trapezoidal metal unit on the side of the injection pump) and vacuum modulator (the blue plastic flying saucer on the fender near the glow plug relay). Lo and behold, the VCV was passing zero vacuum to the modulator at all times (spec is 14 in. or so at idle, ranging more or less linearly down to 0 at full throttle). I swapped the VCV out with a new one, and adjusted it to spec---a trivial job as long as you pull the washer reservoir first. The hardest part was waiting for the seal underneath to come in the mail (not Rusty's fault---apparently it came by rowboat from Germany). I also changed out the O-ring on the shutoff lever, which was oozing oil, while I was there. That, too, was easy, except when I had to deal with the accursed C-clip holding the lever on the shaft. (What do the M-B engineers have against ordinary snap rings, the kind with two little holes for your snap-ring pliers so they don't get away from you? I know now that special tools exist to deal with C-clips, but I didn't have them this weekend when it mattered.) The difference was night and day! I went on a long errand immediately after, mostly about 100 miles of highway driving. Shifts were properly firm when accelerating on on-ramps (but not tooth-jarring), and almost imperceptibly gentle at low speeds and light throttle. Best of all, no more CLUNK on the shift into reverse---I had to look down at the lever to verify that I hadn't just missed the notch and gone from D into P or N. Victory (as it so often is) was short-lived. At some point during the trip I sprung a major vacuum leak---the center air vent snapped shut and now doesn't open regardless of ACC setting, and all shifts went back to the previous state of CLUNKiness regardless of throttle position. A quick look under the hood didn't show any obvious disconnections or other open points in the circuit, so I imagine I stressed one or more of the lines and cracked it/them while manhandling things to get the old parts out and new ones in. At least I can be pretty sure that this new problem is upstream from the VCV and tranny modulator, right? The vacuum lines to the EGR and the other emissions control nonsense down by the air filter are already blocked (how did THAT happen???) so that narrows it down too. Alex Chamberlain '87 300D Turbo '93 Isuzu Trooper '86 Lincoln Mark VII LSC
