W123 Performance/Maintenance: ALDA Removal and testing (OM617 Version of AFC Housing)

The ALDA on am OM617 engine serves to regulate fueling off-boost, so until the turbo spools up it limits the maximum fuel, it has been said it was used to make acceleration smoother by removing the surge of power when the turbo spooled up.
And, if it fails, it severely limits your top end power. Lets pull mine off and see how its working.
➡The gearwrench set of wrenches I have: amzn.to/3sBeeeW
➡A far cheaper individual wrench: amzn.to/3a10VxX
➡Actual 27mm wrench: amzn.to/38qNuGY
➡Some really big groove joint pliers: amzn.to/3Nhjzjc
➡Even bigger groove joint pliers: amzn.to/3wuSceO
➡Impact screwdriver: amzn.to/3LihPoy
➡My absolute favorite hammer to use with the impact screwdriver: amzn.to/3NiifwP
➡Alternative from another fabulous company: amzn.to/3wdKpDh
➡Mityvac for vacuum and pressure testing: amzn.to/3wfHp9I (I honestly don't think you can own a diesel Mercedes without one of these)
(Links shown on this channel are quite likely "affiliate links" which allow me to earn a small percent commission for referring you to purchase these items at no additional cost to you, and it helps me keep making more videos like this)

[@trythistv]

The gearwrench set of wrenches I have: amzn.to/3sBeeeW A far cheaper individual wrench: amzn.to/3a10VxX Actual 27mm wrench: amzn.to/38qNuGY Some really big groove joint pliers: amzn.to/3Nhjzjc Even bigger groove joint pliers: amzn.to/3wuSceO Impact screwdriver: amzn.to/3LihPoy My absolute favorite hammer to use with the impact screwdriver: amzn.to/3NiifwP Alternative from another fabulous company: amzn.to/3wdKpDh Mityvac for vacuum and pressure testing: amzn.to/3wfHp9I (I honestly don't think you can own a diesel Mercedes without one of these) (Links shown on this channel are quite likely "affiliate links" which allow me to earn a small percent commission for referring you to purchase these items at no additional cost to you, and it helps me keep making more videos like this)

[@johnthomley1657]

Just deleted my Alda per your instructions. 1981 300SD. WOW!!! What a difference! Thank you so much for posting this great info.

[@trythistv]

As a note, doing this may make you fail an emissions test, it is unlikely, as in the 80s there was not a lot of requirements, but the EPA can be a bit nasty at times, especially recently, so I wouldn't recommend leaving it off for good if you are in the US and drive on public roads, mostly because if I become well known as recommending that anyone circumvent their emissions devices it would be bad legally speaking for me, so I will never recommend that anyone permanently disable any part of their emissions system. However if you are in another country that does not fall under EPA jurisdiction, or use your engine as part of an off-road device like a generator or such, then its up to you whether you would like it on or off, There are a number of companies that sell a nice little billet aluminum cap so you can completely remove it for off road use, or driving in mexico or wherever you may live...

[@johnthomley1657]

Good to know! I’m in California so 1997 and older diesel powered cars don’t require a smog check. I kept the parts though just in case.

[@termainerobinson5373]

Are you getting alot of black smoke now?

[@R8V8Vantage599]

Thanks so much for these videos, all the info one needs for investigating this issue.

[@trythistv]

Glad to share!

[@johnwight6041]

Another awesome video!!

[@anassnouri6129]

Thanks you for confirming this and explaining with details, shout-out to old benzes from Morocco 🇲🇦 , ima remove mine asap

[@jonm1999]

Thanks once again!

[@h.v.g7882]

Looking forward for this video 📹 👍

[@belowfray5251]

Thank you.

[@vintage76vipergreenBeetle]

Nice info & nice w123 shirt.👍

[@trythistv]

Thanks! I've been testing some shirt types and stuff to find ones I really like so if I have a neat design I can share it with everyone, I love the wireframe w123 design I've got, but I'm not super thrilled with the shirt material, it is super comfy but not very durable feeling, I'm suspecting it might not hold up well, but at some point I'm going to find a shirt material I really like and offer it for everyone

[@ebutuoyebutouy]

Thanks for sharing. Same applies to the om602/3/etc.

[@trythistv]

I figured it might be similar, but I haven't had much experience with the newer engines, good to know this info is useful for far more than just 617s

[@anassnouri6129]

602 n 603 have no bango bolts

[@h.v.g7882]

Will that's a huge difference 😯👍 Will try this om my Mercedes-Benz w126 300sd 😃

[@trythistv]

It has made an unreal difference in how the car feels. I'm wondering if my pump may be a bit worn, as it will not ever make any smoke even without the ALDA, but has a good amount of power, I may look into some of the more involved adjustments at some point so I can get smoke off boost and then put a functional alda on to make it how its supposed to be again, but we will see what I end up getting motivated to do!

[@dlk9854]

Hi there. I should first say that all your videos are to the point, well explained and help a lot. Thank you! I'm sure that they are truly appreciated by all who have seen then. About ALDA on your W123. Q1: Would simply removing it have the same effect? Another comment is that removing something that was a part of the design and having an significant improvement doesn't sound right. It looks like your ALDA was limiting the fuel flow with boost, so it's broken. This explains the car being slow. However, No ALDA should have a similar effect to when you unscrew the ALDA bolt up to the max. With this, you should see a lot of black smoke, which you don't see. I wonder why. I did experiment with ALDA and saw the black smoke above certain limit on my car (same model as yours). I'm willing to try more but would want to better understand what's actually happening with your MB :). Another question I wanted to ask: Q2: What altitude are your at? Thanks and Keep your videos coming...👍

[@trythistv]

What I have heard is that the MW pumps tend to get lean with age, they don't pump as efficiently, and move less fuel, which results in low power, and removing the ALDA can restore some of that fuel to make the car a little peppier. I'll try to answer questions in a logical order, I a bit tired so hopefully it comes out right lol. Yes, removing the ALDA would have the same effect, but then dirt or water could sit on top of the fitting on the IP and get down inside the IP, or at least I feel like it could, there is a seal on the rod that slides up and down under the ALDA. The big issue with mine that unscrewing the screw on top didn't do anything is that the diaphragm parts had somehow cracked or something which led to the pressure causing them to expand rather than contract, so screwing the adjustment out would only have an effect until boost built and then the alda would expand and limit fuelling instead of contracting and allowing more fuel. I am very curious about my lack of smoke, this car has never seemed to have a tremendous amount of power in the higher RPM, but has phenominal low end torque, which usually it tends to be the other way around with a 617, a little sluggish off the line but sets you back in your seat once the turbo lights. I've been gradually heading in 2 directions in all these videos. I'm suspicious if either the timing is off slightly, this engine is evidently a factory remanufactured block, so perhaps the IP got installed off a tooth, so at some point I'll be checking the injection timing. or the 2nd option is there is something wrong with the pump, it has gone lean or was poorly adjusted from the factory and needs the full load adjustment turned up a hair, so that may be happening at some point as well. I'm around 1300-1500ft above sea level, so not anything too wild. Hopefully that answers what you asked and I didn't ramble too long lol

[@dlk9854]

@@trythistv Makes sense, and thanks for spending time answering the questions. It's interesting to hear about your power/torque pattern. I'd be quite curious to see where your timing is. If it's too advanced, it might explain it, but it should then result in more black smoke at acceleration, which isn't the case. Anyway, if it runs well and you don't see any other "bad symptoms" - enjoy! :)

[@w124mercedes7]

I've got a 1987 300d with the om603. The first time I drove it I was surprised how much power its got. When the turbo spools up it pulls very well. Only has 160k Miles and has always been maintained. In the past year I have put about $3000 Just into parts and tires. Getting ready to order all new upholstery for it. Its too bad mercedes don't build cars like this anymore.

[@trythistv]

The 603s do make some good power, I've never owned a 603 powered car, but I have driven several, and they are nice! It's worth every penny in my eyes keeping my cars on the road. I just drove a few hundred miles in my W123 and man was it smooth and comfortable.

[@w124mercedes7]

@@trythistv i was looking for a w123 and couldn't find anything that wasn't rusted. Or had very low quality paint jobs. Once you put a cheap paint job on a car Its really hard to bring them back unless you remove all the trim and glass then strip the paint. I restored cars for 30 plus years and really wanted a w123 And do a 0m603 swap. But I found a low mile w124 with zero rust and nice body. I paid $3.600 for it and have put about $3000 into parts and tires. I rebuilt the injectors and turbo about 100 miles ago but I think im going to Get a bigger turbo .injectors and have the pump turned up. Should really move when finished. Unless I sell it and get an older model. I like the older body style.

[@trythistv]

The W123s are getting harder to locate, A few years ago they seemed to have nearly no value, I saw decent 300Ds all day long on marketplace for around $1000, but not anymore. I'm glad I got mine when I did, I do need to repaint both of mine, and I'm figuring out how I want to do that, I'll be removing all the trim I can, but likely will leave the glass, as that would add a ton more work. My brother used to own a body shop so he may be able to provide some words of wisdom, and tools of the trade to make sure I get a very nice, very long lasting paint job.

[@w124mercedes7]

@@trythistv i restored and painted classics for 30 years or more. The most important part of a good paint job is quality prep work and good name brand paint. Be prepared to spend $1000 on matterials such as abrasives. Primer. Sealer. Base coat and clear coat. Look for a good name brand high solids European clear coat. It will outlast you if properly cared for. A friend has a old caddi Eldorado I painted 15 years ago and still looks fantastic. The saying you get what you pay for is true when it comes. To paint work. I won't do a paint job for under $5k but I paint door jambs and all so it doesn't look like a repaint. I will probably have $2k into my w124 Good luck on your projects and enjoy them. They are very fine cars

[@teesaeed6529]

Thanks lot for this video. Have a question would it effect the fuel consumption?

[@trythistv]

It could drop the fuel economy slightly, but mainly due to the fact that the engine is making more power. More power will burn more fuel, if you can keep your foot out of the throttle and modulate it instead of flooring it at every light to feel that rush of newfound horsepower then it should have a very minimal effect on mileage

[@teesaeed6529]

@@trythistv ! thanks again for a quick response, Keep up that good work you are doing. I am watching your channel for a while and was able to fix lot of minor stuff myself on my both 123 and 126 both 1985 been educated through you and saved lot of money. HE may bless you.🙏

[@xsiaze]

do you also plug the plastic pipe thats coming from air intake to switchover valve (boost protector) ??

[@trythistv]

Yes, otherwise you'd be leaking boost out of the manifold. Entirely possible to install a plain bolt in the manifold as well.

[@xsiaze]

@@trythistv yep, i just bought some alda delete kit , thank you sir!

[@AlexOnParkwood]

@@trythistv Ah ha! Now I have a complete understanding. The little billet aluminum cap is not the only task at hand. A "plain bolt" in the manifold is also a necessity. #learning

[@AlexOnParkwood]

@@trythistv Size?

[@DYLANTRIES]

What is sd314 nozzles??????????????????? I need nozzles for my 84 300SD asap

[@trythistv]

IDparts used to sell them: www.idparts.com/firad-injector-nozzle-314-an0sd314-p-3085.html but they are out of stock at the moment. You can probably source them somewhere, then you'll need either a pop tester or take your injectors to a diesel shop that can pop test and balance the opening pressures so each cylinder runs optimally.

[@nutragardens6632]

😮

[@gregoryarrieta3675]

And how did it go with the smoke?

[@trythistv]

Zero smoke at all throttle positions, load and rpm. I think my pump has either gotten lean with age (needs full load turned up) or the timing is off (needs to be adjusted) as there should be some amount of haze at least with the ALDA non functional.

[@gregoryarrieta3675]

@@trythistv OK thank you! It really is amazing that you don't even have a little smoke! How many degrees is your injection pump on?

[@trythistv]

@@gregoryarrieta3675 sorry I never got back to you. I'm going to have to make a video on timing pumps, as I checked mine and it was set at 16 degrees btdc... Stock is 24 degrees, and advancing to 26 or even 28 can get more power at the possible expense of harder cold starts and risking higher cylinder pressures that could pop a head gasket if it is already weak. I advanced mine from 16 to 20, because I was just vaguely eyeballing stuff, but I need to do it proper and show both ways lol as well as getting mine right where it needs to be.