1993 Mercedes w124 diesel modifications
 

Did my first engine modification yesterday, removal of throttle plate(this is a diesel engine)

People I talk to say it is purely for creating vacuum to activate EGR nothing else, since this car was imported it has EGR, many same engine and yearmodel cars were built without this.

This is how it looked like before
https://i.postimg.cc/kGCkM9Sk/20200702-113945.jpg

Nice, finally gone and yuk full of soot from the EGR
https://i.postimg.cc/9FWvvmC9/20200702-124253.jpg

End result
https://i.postimg.cc/P50VrTs2/20200702-124240.jpg

And what can I say after driving 160km(100miles)
WOW!!! :eek: never thought it would make this big difference, she has a lot less engine braking so I can coast a lot longer (automatic transmission) and partial throttle response is a lot better,
in fact partial throttle response is so much better that I can leave her in D instead of manually shift to 3rd gear when city driving at the speeds 30km/h and 40km/h.
Same thing in roundabouts no need to use kickdown(or manually downshift) to get her initally moving out of the roundabout, she scoots a lot quicker with less throttle input (or rather the need for full throttle in city driving is gone now) :thumbup: :)

Another positive is that engine stays cooler, before even during the winter short idling in traffic lights made temp go quite high and it was slow to go down to normal again, now it is slow to rise and fast to go back to normal :)

The bigger question is, how will this affect fuel consumption :confused: my guess is probably for the better :D

What about the effect of this mod to the brakes? Aren't them vacuum-assisted too? On a sidenote, in Brazil I'm aware some people adapted throttle plates to Mercedes-Benz OM-314 engines in order to improve engine-braking, even though I would rather resort to an exhaust-brake for that matter.

No effect at all on brakes :thumbup:
like all diesel engines this also has a vacuum pump for the brakes and since it is older style mercedes, this vacuum is used for central locking mechanism and engine shutof also

Like I wrote above this engine was also made without EGR, only difference is intake, exhhaust, a few linkages and pipes between exhaust and intake

So this throttle plate only function is to allow intake get clogged with soot from EGR :rolleyes:

Later I will get the non EGR exhaust manifold and intake to increase efficiency even more and make room for water injection (this EGR intake is also very big and makes engine bay crowded:mad:)

Isn't it going to fail inspection if you disable EGR?

Here no, but depending on where you live it might, the egr is still there and everything around it

the thing with EGR on diesel is that if you want it to work it needs cleaning from soot almost once a year, google if you wish to learn more :thumbup:

Does water injection work in a diesel?

Of course :thumbup: it is great on supercharged engines but even NA benifit from it, reduces soot and NOx, cleans combustion chamber

The downside is that water freezes during winter

Adding some alcohol prevents the water from freezing, plus it becomes easier to vaporize.


Since it had a throttle plate, it got me wondering if Mercedes-Benz would've eliminated the vacuum pump.

Yeah i know, methanol is the preferred alcohol, it even adds some energy (power) problem here is it is very very expensive, only cheapish alcohol is E85 and then you gotta remove the gasoline after blending it with water.... only other solution is washer fluid wich also is ethanol here and quite expensive :rolleyes:


My though was that they maybe also used the vacuum for the automatic gearbox but they did not, it seems to be only EGR wich is nice :)

Is homebrewing vodka totally out of question? :D


So, does its torque converter not feature a lock?

I have thought about it :D still very expensive here atleast :eek: (and illegal)


exactly, no luckup whatsoever so converter always slips a little

Since it's usually done by inmates with improvised resources, still seems to be worth a try. Plus you might be able to use raw materials that would otherwise go straight to the garbage.

HAHAHA :p well I dont think inmates are allowed to drive cars either, If i had time to do something like that it would be used to collect and filter WVO instead. Perfectly legal and saves a lot of money :cool::)

Alcoholic fermentation didn't change too much through time. BTW is it also outlawed to make craft beer at home in Sweden?


If you could do both the WVO collection and filtering and some experiences with alcohol it would be great. Well, it would be quite interesting to say the least if Sweden shifted from E85 to straight hydrated ethanol (E96h) used in Brazil, and such transition might not be too bad nowadays that flexfuel cars in Brazil resort to heated injectors when fitted with port-injection, while direct injection usually doesn't require any starting aid. Well, as a last resource something analogue to the grid-heater used in some heavy-duty Diesel engines could also serve well to a port-injection flexfuel instead of either a supplemental gasoline tank for cold starts (widely used in older dedicated-ethanol and early Brazilian flexfuel cars) or heated injectors. A small-volume Volkswagen-based minicar from the '80s named Dacon 828 resorted to a glowplug out of the Volkswagen EA827 1.6L IDI Diesel as a makeshift intake heater as a cold start aid for the ethanol-powered engine.

Have done quite many kilometers on wvo before, quite time consuming to collect wvo, filtering is pretty easy once you know how, have room for it and have the setup fixed

For us normal deadly converting a car to E85 or E96 and adding a small gasoline tank for startup is much easier, also how they did it in brazil from my understanding

Blending is easiest both with vegoil and ethanol, no need for expensive conversions :thumbup:


Been looking into both propane and methane to boost power/increase economy and the kits I have found are all quite expensive :( :rolleyes:

Water injection can be made quite cheap :thumbup::)

The auxiliary tank used to be the rule at least until 2010 when Volkswagen released a version of the Polo fitted with electric pre-heating of the fuel, and in few years this became the prefered approach. I don't remember if any new car still has this tank.


Blending is easier with ethanol than with veg oil. At least when it comes to compatibility with emissions control devices which has been more critical on Diesels.

yup totally is :thumbup: , I keep forgetting that IDI cars and mechanical fuel pumps (ususally before 1995) is now very old tech :o :eek:

I would say the most problematic with blending in modern diesels is the direct injection, injectors, common rail and electric fuel pumps (all the stuff modern)...

while modern gas cars are great for blendning, with the modern electronic adjusting for the more fuel needed automatically, carburettors are way more difficult in that regard

IIRC the last "modern" naturally-aspirated IDI was the Peugeot DW8 which lasted until 2007 in Europe and IIRC a bit longer in Argentina, even though its distributor-type fuel pump already featured some electronic controls.


The most critical element is actually the particles filter.


I have seen some folks rejetting small-displacement motorcycle carburettors in order to run on both gasoline and ethanol, before Honda introduced EFI and flexfuel ability to the CG in 2009.
https://1.bp.blogspot.com/-Kxg7MT_sR...419_115929.jpg

Do you notice more soot emissions now the EGR is disabled? Off course, it triggers internal pollution, but EGR also helps warming up the engine faster and it's needed for the regeneration of the particulate filter. But I recon your car doens't have such a thing :D.

Are you planning aero mods?

https://external-content.duckduckgo....jpg&f=1&nofb=1

only notice a lot better running, if i had more time i would clean the intake from EGR goop aswell, gonna change it later anyway...

soot is invisible in rear mirror just like before, only notice a little gray haze during startup(like before) if weather conditions and lighting are right

she gets warm just like before after about 3km(2 miles) for pretty warm and fully warm at 5-6km (3.5-4 miles) only notice cooler running when fully warm in traffic, no more seeing temperature needle rise a lot during idle wich probably is because of the removed throttle plate(more air)

EGR function is to lower combustion temperature to reduce NOx--make the burning cooler, how this is supposed to help warming up engine is a riddle to me :confused:

and yes no such thing on this car :thumbup:

no plans for this at the moment atleast, bit did change wheels to more aerodynamic :cool:

When the hot exhaust fumes are recirculated at a cold start/cold engine, it will help warming up slightly. Not with every car, sometimes the EGR is deactivated untill operation temperature is reached, to improve smooth running.

Not only the heat reintroduced to the intake stream, it's also worth to notice the lower density of the recirculated gases compared to fresh air makes it lighter for the engine to compress.

I am actually thinking of making rear wheel skirts, think they look cool

here is picture of how she looked like when i got her with 16 inch wheels

https://i.postimg.cc/nhxjbMP7/fram.jpg

and how she looks like right now with 15 inch wheels

https://i.postimg.cc/G3yzyQwW/20200430-143144.jpg

still trying to get time to change the springs, lots of rain now so the helpful dude has no lust to change them untill the weather gets better LOL

I'm not a fan of rear wheel skirts, but anyway, seems like those hubcaps were already somewhat of an improvement regarding aerodynamics too.

I have been noticing how she constantly runs better since removal of the throttleplate

there are two hills on my way to work wich before this mod i had to give full throttle else i could not make it to the top, well not anymore :thumbup::eek:: :D now i can back of the throttle before reaching the top

And I am also noticing more free revving engine, on the stretch of motorway while keeping throttle steady at 85km/h, the slight downhill going north resulted in my speed reaching 105km/h :eek: :thumbup:

The only time something analogue to a throttle plate in a Diesel engine would be desirable is the "emergency flap" fitted to some stationary and marine engines in order to choke them in case of a sudden engine runaway.

Exactly :thumbup:

On a sidenote, some newer engines have been fitted with an electronically-controlled throttle plate due to emissions compliance, in order to allow a higher rate of warm EGR flow. Seems to make more sense than the mechanical-link throttle plate you had, even though it might enable a somewhat similar effect with fewer precision.

https://www.youtube.com/watch?v=GXQPsAW-iZA

so now with four fuel fillups, 80 liters(21 US gallon) and 1290km(802 miles) since the removal of throttle plate my avarage consumption has been 6,16liter/100km or 38.2 US MPG

seems like a trend :D :thumbup: on friday it is time for the next fillup, exciting to see what it will be by then

That's quite a good mileage for a car of this size. When an uncle of mine had an early Suzuki Vitara with a Volkswagen 1.6D engine swap, it got around 5.2L/100km on a regular basis with my lead-footed uncle driving it. Considering the Vitara had the manual, while your Mercedes has an old-school automatic which charges its toll on fuel-efficiency, it's quite impressive.

totally agreee, I am also very impressed, had a mercedes 190(w201) or "baby benz" from 1987 with the same engine and manual about 10 years ago I managed 5,4liter/100km with this at best and ususally about 5,5liter/100km

the only difference between the baby benz and my current mercedes is that is “Diesel ’89” initiative wich gives a slightly better swirl and a whopping 3 more hp, this car is both automatic and much larger/heavier

also had a baby benz with a 5 cylinder 2.5 diesel 90hp also from 1987, very front heavy and not that fuel efficient at 6.5liter/100km


also had two bmw 525tds touring (1993 and 1994) 2.5 liter 6 cylinder 143hp wonderful engines and cars, on real diesel these run about 6.5liter/100km but the crappy diesel from the pump here got about 7.2liter/100km


had a few vw diesels too, vw golf, had a 1988 1.6 NA with awesome 54hp the most fuel efficient car ive had 4,5liter/100km but engine had bad compresion :eek:

also had a 1992 vw golf ECOdiesel same 1.6 engine with turbo and 68hp this was always thirsty at 5.6liter/100km but after turning up fuel it actually got down to 5.2liter/100km and went a lot better

Those older BMW Diesel engines are often reported to be great.


At least since the '70s the sale of Diesel-powered cars is banned in Brazil, even though some (mostly station-wagons and light-duty cargo vehicles) conversions were tollerated and could be legally registered until '93 and are grandfathered. The engine which was fitted into my uncle's Vitara was most likely taken out of a VW Transporter Panel Van.
https://1.bp.blogspot.com/-4ag4fycXq...o-esquerdo.jpg

They do have their problems, The mercedes 5 cylinder 2.5 om602 is much better design (and 20 valve om605 2.5 liter is way out of the league above from tuning/durability standpoint)

First problem is the injection pump wich is semi electric, you can mount a mechanical pump from an earlier 2.4 6cylinder (the engine before) also early engines had waterpump with plastic impeller and the would often crack in the shaft resulting in engine overheating and literally self destructing, the cylinder head channels are somewhat tiny resulting in max power potential of only about 210hp and for durability about max 180hp

and like most 6 cylinder engines it also has problem with cooling the most rear cylinder....

Wonderful smooth engines, miss my bmw sometimes....

Love those bmw 6 cylinder engines


In vw they used the aaz 1.9 engine often in transporters or later cars, VAG began replacing the 1.6 with the 1.9 around 1992-93 if i remember correct

Haven't seen one of those for a while, but I remember having seen many in the '90s mostly with Argentinian and Uruguayan plates.

allright time for the update, now I have driven 1670km(1037 miles) and used 103 liters (27.2 gallons) since removal of the throttle plate

this gives fuel consumption of 6,14 l/100km or 38,3 US mpg, I am very impressed myself and this is pretty normal driving(no ecodriving) :eek:

now it is time to fix brakes :rolleyes:, auto fluid change, oil change and spring change :thumbup:

Did you notice any increase to braking distances after getting rid of the throttle plate?

you mean engine braking? yes I can coast a lot longer now since engine brake is a lot less :thumbup:

Yes, that's what I meant.


Sounds good from a strictly efficiency-oriented standpoint, but did you never felt it desirable to retain some engine-braking under certain conditions? Maybe an exhaust-brake could be desirable.

exhaust brake? you know this is a regular car and not a big truck :confused:there is no risk of brakes getting overheated if I need to use them(rarely) so adding a exhaust blocker and reducing engine efficiency is not on the menu

so finally got to change the springs, what a lift both in looks and literallly :D(from the ground)

https://i.postimg.cc/tJrnjzgG/left1.jpg

https://i.postimg.cc/rmw8k2Rz/left2.jpg

https://i.postimg.cc/FHvzBqpk/right1.jpg

https://i.postimg.cc/FKRrtQLz/right2.jpg

wonder how and if this will affect fuel consumption :confused: atleast no more scraping everywhere :):cool:

now next thing on the list is rear brakepads, atf oilchange and regular maintanance :thumbup: