W126 300SD Mercedes-Benz OM617 ALDA Delete - Step by Step 

Glad it worked out for you!

How much better is it

Because your alda was broken, removing it allowed the stock 120hp to return, you didn't increase performance.

Peter you kill me my friend. LOL..... My ALDA is indeed "“F…. up". ha ha..... I had planned to disassemble it for inspection. It certainly is nice going up hills in 4th gear.

@@ImpalamansGarage Mr. Imapalman, a scientific dissection of this highly precise instrument documented in your usual neat video production presented as a statement of principles would be absolutely marvelous and most welcomed! Your buddy Peter from Kansas. P.S. I have been told since first grade that I am an highly “inappropriate” person and my behavior left things to be desired…… They forgot to mention deplorable…..

We're on the same page. An ALDA dissection is in the cards for sure.

If you have plenty of power already, yoir issue might be somewhere else. However removing to see the effect won't hurt anything. Can always reinstall.

I've had zero issues after the EGR and ALDA delete.

What's the big difference after removing it?

Well

This was my first one mile roadtest comment

Previous owner of this car did the R134 conversion. The AC on this car works well so for now I won't fool with it.

My ac is as cold as the R12 system was

Dude the difference in around-town drivability after removing the one from my car is nothing short of astonishing.

Switch over valve on mine was literally brand new because I broke the original one a couple years ago. LMAO So I know that was not the issue.

@@ImpalamansGarage I'm glad to hear this. However for me at this time it's staying. My turbo needs a bearing rebuild first. Looking forward to doing this in spring.

Someone removed the valve in question on your car previously most likely. Mine is gone now as well. Car uns fine. Of course this makes the car not original. I kept everything I removed in case I want to sell later.

I see no reason to keep it on the car.

@@ImpalamansGarage if you send your pump in for 7.5 mm elements, it’s required to be sent in with the pump.

@@Ajme-kb4os I've heard that. It's now safely tucked away in a cabinet in a box and labeled. :)

@@ImpalamansGarage I put a holset he221 turbo on my engine. But never touched the Alda, maybe I oughta adjust mine out some and see if it helps driveability until I can afford sending my pump in. Thanks for the video!

@@Ajme-kb4os What change in performance did you realize by upgrading the turbo ?

It just has a threaded plug in there that can be removed at any time.

@@ImpalamansGarage what did you do with the line going from the intake manifold?

@@peterkok2528 I use the top port for my boost reference , isnt it the same tho ?

LOL.... don't know. We can ask. Benz Force has one too. Same price. Doomsday's part is prettier though. I know one thing. It's not going back on unless someone makes a very good argument to the contrary. I've seen no extra smoke emitted from the tail pipe. It has literally transformed the drivability of the car.

@@ImpalamansGarage I'm not going ask Pierre about that modification.🤐😁 I think he made a video about ALDA. Can't remember right now. If I owned a diesel MB, I would do the same modification.

I've seen no adverse effects or changes in fuel economy. Maybe a tiny bit of extra smoke? Primary impact is GREATLY improved off-idle performance. You basically get full fuel off idle so driving in heavy traffic now is very nice. To those arguing that this mod will make you roll coal where ever you go, go take a look at the motortrend retro review of the 300SD. Watch their performance tests and observe the diesel smoke in the old video. Keep in mind that was a brand new car they were testing.

All country boys sound alike. lol

@@ImpalamansGarage thanks for making these videos. It's nice to have first hand experience with deleting or modifying something to see if its even worth doing.

@@tylerhamilton181 Removing the ALDA is sort of a controversial thing because it is an emissions device in addition to an altitude compensator. However if it is broken and the internal vacuum of the capsules has leaked out, it will rest in a more expanded state and will be more prone to press down on the rod on the pump and thus limit fuel. In my opinion I'd bet money that the ALDA on many of the high mileage Merc diesels from this era are non-functional. If it WERE working properly the car would not be such a slug and you would not have to adjust the screw all the way out just to get the car to move.

@@tylerhamilton181 If you decide to have your pump modified for performance, you will need to consult the company that does the work about the ALDA. They may require that you send it to them. Hold on to it if you remove it.

I believe it's an acronym from German words. It's dual purpose: Altitude compensation and prevention of smoke and low RPM (emissions device).

Yes. All you do is install the cap ..... "delete kit". You are covering the rod that was being depressed by the ALDA. Depressing the rod limits fuel flow. My ALDA clearly was not working properly and they are really hard to come by. I might be able to repair it. We'll see.

I broke mine by hitting it with a hammer

You can’t get the Alda assembly as it it part of the fuel injection pump I was told by Mercedes’ Benz dealer

It is calibrated with the fuel injection pump

@@rb.867 I'd bet good money that 90% of the ALDAs on all OM617 engines with a lot of miles on them are non-functional. Meaning the copper capsules inside have leaked and no longer hold vacuum. This causes them limit fuel much more than they were designed for.

Monta King - Yes the 603 does have one. Recommend reviewing the comment on this video by user "INOVA HIGHTECH Ltd". That will explain exactly what the ALDA does. Mine is probably broken or leaking but I won't know for sure until I disassemble it. Removing it most likely restored off-idle performance to normal. I'd say the risk is zero. My car runs great and I've seen no changes from the exhaust. This is an emissions device plus also an altitude compensation device. The question I'd ask myself is: "Do I have to floor my car to make it do pretty much everything?" If the answer is yes, there is a good chance the ALDA is broken, leaking or not adjusted properly. Check this out: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-i6TZ2bnlAjI.html

@@ImpalamansGarage Thanks so much. Very helpful.

It is there to cut the engine power due to over boosting the turbo charger, but don’t hold the throttle to the floor and roll coal and you will be fine. I drive responsible and am no kid myself anymore so that’s the only way I drive.

We'll find out before too long!

I ordered a bunch of gaskets and seal for the oil filter housing, it looks like it is my main oil leak, have you ever replaced all of the seals and gaskets on a 617 engine? If so ,do you have. Video?

@@rb.867 Made a video of the oil filter housing and oil cooler line replacement. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-7OkHBCwWdzM.html

The ALDA is an altittude compensation device to keep the engine from burming too much fuel at high altitude. How high? Don't know. Too much fuel equals lots of black smoke. Also it supposedly helps with smoke emissions in regular off idle part throttle conditions. Now having said all that go watch the Motortrend retro review of the 300SD from the early 80s on youtube. Watch how much A BRAND NEW 300SD smokes during their acceleration tests. You can see it in the footage. My car runs fine, performs like a normal 120hp car should, doesn't drive like you're towing a boat anchor and still gets the same mpg it always did. So in my oponion, no it does not hurt the engine.

@@ImpalamansGarage Thank you for the info, my concern was more on the longevity of the motor. I currently have 150k on it and trying to get it to the 500k mark lol. Would you mind sharing the link to where you purchased the ALDA Delete?

@@sreyes1103 www.doomsdaydiesel.net/product-page/alda-delete

The link for the ALDA and the plug for the intake are in the description of the video.

@@ImpalamansGarage I found the website and ordered this delete kit as well as the EGR delete