VLOG - Mercedes 300SD W126 - OM617 Vacuum Routing Without EGR - Plus Viewer Appreciation Time !!

[@Engineerd3d]

Thank you for posting this. It allowed me to simplify the vacuum system as well as alleviate (possibly cure!) a poor shifting syndrome my 84 had (shifts up very quick but refuses to kick down for more power). At the very least it is no longer polluting my intake with soot!

[@ImpalamansGarage]

Bowden cable adjustment should cure a lot of that.

[@Engineerd3d]

@@ImpalamansGarage I already did the Bowden cable. I suspect the egr system was leaking allot of vacuum and caused poor shifting. Once eliminated it shifts much better!

[@hanseich]

I’m very seriously considering removing the vacuum pump from my engine, and replacing it with an electric one. This would reduce the risk associated with the bearings breaking in the vacuum pump. What I’m currently trying to firifre out is how to design an electric vacuum pump system, as a UP30 (pump I currently have) is only spec’ed to run a few hundred hours (total life span). It looks like these pumps only run very shortly in electric cars. I might have to forgive out a system like that. Thanks for this video, it helps understand the existing system.

[@danielstein5290]

Thank you sir, just got a 83 300sd Did the brakes (rear are still needed to be done, had to replace a couple hard lines in the rear but as of 11/12/24 no more leaks! (3 pre made lines and two unions lol) Next is EGR delete and possibly a new air filter setup (straight to turbo or with 45 angle pipe to a new filter) as my OEM filter shakes but I’ll check that soon Thank you !

[@ImpalamansGarage]

Yeah making the stock breather NOT rattle is a real challenge. In a later video I came up with a mod to keep it steady. It's here: kzbin.info/www/bejne/Z3PXYXmCZ7ytj80

[@danielstein5290]

@@ImpalamansGarageI’ll take look! Thank ya!

[@elvisquezada2113]

Really enjoy your videos . Thanks for guiding us to keep our Benz alive and running in top shape . I started driving my 1983 300SD daily now . Really enjoy driving it better thank my 2021 Corolla . Could you do a diy for a couple overhaul of the AC unit . I am planing replacing all hoses , compressor, sensors and everything associated with the cooling system. Thanks Mr. Impalaman !!

[@sr22dvr]

Looking forward to the intake clean out video. That should be interesting. Thanks for the info on the EGR delete.

[@tylerhamilton181]

I just picked up a 1982 300sd. Obviously it's got vacuum issues so hard shifting and vacuum leaks everywhere. Thank you for the egr delete walk-through. I'll be deleting mine asap.

[@CESARP35]

Very well explained Impalaman, much appreciated.!

[@vintage76vipergreenBeetle]

As these cars are getting older, the lesser vacuum hoses it has the better. 👍

[@ImpalamansGarage]

No argument here.

[@grizzladams]

Great info, nice custom socket from the viewer...good stuff

[@bradalloway3232]

Wow! Next day service even. You can't beat that. I'll be deleting all of that this morning while replacing the a/c compressor. My project is almost complete. Your videos have been an incredible help. Thank you and death wish coffee for making this project come together.

[@zach359]

Mike I did the same thing to my car, but am having issues with shift quality now. I will be putting back the valve for the vacuum bleed down and supply to the transmission. I’ve done more reading and that valve is necessary for proper vacuum to the transmission.

[@ImpalamansGarage]

All these engines have their own little quirks. What I have done is tweak my bowden and modulator to dial in the shifts in the absence of the EGR vacuum circuit. One thing to consider is that the first two years of the OM617 did not come with EGR. It was added later as a requirement for North America.

[@wernerdanler2742]

Hi Mike. I never had any problems with my vacuum system on my 300d so I never messed with it. But noticing the double fire wall on your S class, I remembered a friend had a 300sd and I drove it once. That double firewall makes such a difference in the noise level inside the cabin compared to the E class without that. I also remember trying to use the cruise control and after a bit the throttle stopped responding. So I pulled over and discovered one of the c clips had come off. I reset the linkage hoping it would stay on but it came apart again. So I had to stop and reset it. As long as I did not use the cruise control it would work just fine. I think I did use a paper clip on it to help and later got the c clip for it. So watch those c clips on all that linkage!

[@donatienza6738]

11:36 I believe that line is for the vacuum shut-off valve so that the engine will stop when you turn it off with the key.

[@ImpalamansGarage]

Yeah! Thats it!

[@nickvilla8578]

this video has helped me immensely i appreciate the info!

[@ryankc9oza118]

Thanks for the video. This helps alot

[@danpicocfp6276]

great video

[@deadmanhiking9260]

AT the 13:20 you say you replaced the funny looking connector with a tee..I really do not see how that would make any difference, a tee connector and the funny looking one all have 3 branches..so really what would the difference be? I just bought on of these and am trying to do this egr delete so any help would be really appreciated.

[@ImpalamansGarage]

Yes I could have left one of the Y type stock rubber vacuum connectors in place but there are really old and loose. So I elected to simply use a standard T connector from the local parts store. Works the same.

[@garylanders1470]

Awsome!

[@shaneharrison6940]

Thanks , good info, awesome

[@dixiemae5042]

Where did you get that pdf of the vacuum diagram and do you have others for the Mercedes diesel specifically the W123. Thanks

[@ImpalamansGarage]

drive.google.com/drive/folders/1n6v8R9LDqlj7NafPFF4GFOQbUOjBkPeh

[@dixiemae5042]

@@ImpalamansGarage thank you!!

[@jordansterling9184]

Would it be theoretically possible to route everything like you did without physically removing the EGR and thus just disabled it. The Valve should be shut on the egr anyway so without any vaccume supply, shouldn't it remain shut. I'd prefer to leave mine on if there was a way to disable it instead of doing the full delete? Thanks for all the videos! I've been watching many of them since getting my 84 W126.

[@ImpalamansGarage]

I agree with that theory. It "should" stay shut if no vacuum signal tells it to open. My concerns are: 1) The EGR vacuum connection leaking and causing issues with all other vacuum operated devices. 2) The EGR valve leaking unbeknownst to you allowing a tiny bit of exhaust into the manifold. These concerns might be unfounded but that is why I removed the mine. (That and I think the engine looks better without it) I can appreciate the fact that you want to keep the EGR on the engine to retain a factory appearance however.

[@eternalbeing3339]

I did the egr and alda delete on my 82 300sd w126 and wow what a difference. It accelerates like a gas car now, feels more powerful. But my shifting is kind of rough. Is yours like that? Anyway to fix?.

[@ImpalamansGarage]

First thing I would check is to ensure there are no breaks in the vacuum line to the modulator on the transmission. Make sure you have good vacuum to the transmission. Then move on to modulator adjustments in small increments to dial in shift quality followed up by bowden cable adjustments to regulate shift timing. The transmission in one of these diesel Mercedes will never shift like a gasoline car. It's the nature of the beast. All just my opinion of course.

[@matan6737]

Hey boss, any chance you know where the T that runs the dampener goes to in the other direction? The T that goes VCV, Trans, and somewhere else?

[@ImpalamansGarage]

The three ends in the diagram that are not connected to anything are labeled "a", "b" and "c". "a" (lower right) goes into the passenger compartment to power vacuum devices in there. "b" goes to the transmission. "c" (upper right) goes to the power brakes. See the diagram key at the 5:28 mark in the video.

[@matan6737]

@ImpalamansGarage Thanks, got it figured out, at least to the point where it shifts smooth. Only other thing i cant get is the device that sits on the half firewall plate in front of the brake booster, has an electrical connector and two vac lines, one top one bottom. Both on mine are disconnected. Everything seems to work fine, but im not sure what that little module is supposed to do.

[@bryanzurlo882]

If my EGR is still hooked up but unable to hold vacuum, would that leak cause shifting issues and a delayed engine shut down? Or is it on a different part of the vacuum diagram? Great videos!

[@ImpalamansGarage]

Vacuum leaks can cause a variety of problems. I would make sure all vacuum lines are replaced. The hard line from the vacuum pump to the brake booster area is fine most likely. Those are tough. The plactic T fitting near the booster is fragile. Be careful there. Once you are sure all your vacuum lines are good to go I would plug everything except for the one going to the engine shutoff to see if the engine stops properly. If not, your engine shut-off is something else besides vacuum related. Once the engine shut off is sorted, I would move on to the transmission. Here is an excellent document on resolving shifting issues: drive.google.com/file/d/1MgS0u5LJFObsyYUFwSv3qFDa-JHBYCD8/view?usp=drive_link

[@bryanzurlo882]

@@ImpalamansGarage Excllent, thanks for the info!

[@kyleguitarman123]

Great vid thanks 🫡

[@tydale8629]

I did the same thing.

[@ryankc9oza118]

Have you replaced your vacuum lines? If so, wheres a good place to buy quality line and tees?

[@ImpalamansGarage]

Actually I've not replaced any of the hard line. I've tested it off the car and it's still good to go. I've not shopped for any. give your local Mercedes dealer a call. You never know what they might have. I've heard Covington Mercedes in Louisiana is good. Partsgeek sometimes has stuff that no one else does and of course there is always Ebay.

[@ryankc9oza118]

@@ImpalamansGarage thanks. Mine sometimes is hesitant to shift 3rd to 4th. Surges some times. But bought mighty vac to test stuff

[@ImpalamansGarage]

@@ryankc9oza118 A combination of bowden cable and vacuum modulator tweaking will probably fix that.

[@MarkShinnick]

From 1979 thru 86, a truly idiotic progression of unreliably stupid complications !!

[@ImpalamansGarage]

No arguments here !