Any KE-Jetronic Experts In The UK? M103 W124 (or EFI/Turbo?)

[Will]

That must be the crazy part then? $millions went into developing the system in your car and there are parts catalogs available that will tell you all the part #'s so you can order replacements and well documented instructions on how to fix that system.

Do you really think that you have a friend that can do it cheaper?

True that millions went into developing Jetronic but if the OP is modifying the vehicle with forced induction then I think the benefits of spare parts, instructions and R&D are a moot point anyway in this instance.

I don’t think the original fuel system on these cars likes forced induction really and it is lacking in features that would be beneficial for such a conversion nowadays.

 

[alabbasi]

I don’t think the original fuel system on these cars likes forced induction really and it is lacking in features that would be beneficial for such a conversion nowadays.

This is different to the OP's comments on whether it was cheaper and easier. I can't imagine it being either under any circumstances to fabricate a new fuel injection system from scratch, but yes a more modern fuel injection system can be more tunable.

FYI - CIS was used on forced induction cars including the Porsche 930 and Ford Capri Tickford turbo and the injectors used in the OP's car as the same the ones used in the 190E and the 450SEL 6.9. I think they have capacity.

 

[DanMorgan]

As your dogleg box came from a cosworth it should be the long input shaft version, so you need the older solid flywheel to match. I'm assuming your going to bin the EZL and dizzy and run 6x coils? If you are it wont matter if the flywheel is for a 4 or 6cyl engine, if your keeping the EZL setup you need the proper M103 flywheel.

The gearlever assembly itself is different for a dogleg box, though the 3x linkage rods are the same for any manual w124. The pedal box can come from a 190, w124, w202, and I think w208.

The front section of the propshaft is longer on a manual w124, you will struggle to find that as there are 3 different versions. The front section from a w210 can be made to work in it's place.

The part that everybody forgets is the clutch fluid feed line from the brake reservoir to the clutch master cylinder, it has a plastic push in fitting that can be a pain to get right.

You may need to think about a diff upgrade to a 210mm version, the small diff the 300e has wont last long. That use's shorter drive shafts, but a longer propshaft.

Thanks for this reply!

Yeah - all going for modern, more reliable stuff - This is the kit they'll be using - M103 EFI kit and also a video of someone doing a review -

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(mine with be a twin turbo setup but im not going for crazy power just the "coolness" factor).

Good point with the clutch fluid feed line - will add that to my notes - I was always under the assumption it was a straight swap apart from that the propshaft had to be modified as the 190 has a smaller centre bearing?

Diff will be upgraded too eventually - will nurse the current one just so I can get the car on the road for a bit haha

 

[DanMorgan]

True that millions went into developing Jetronic but if the OP is modifying the vehicle with forced induction then I think the benefits of spare parts, instructions and R&D are a moot point anyway in this instance.

I don’t think the original fuel system on these cars likes forced induction really and it is lacking in features that would be beneficial for such a conversion nowadays.

I've spent enough time messing with the K-Jet stuff and breaking down too - Moving towards a modern setup that'll be far more reliable going forward is more desirable for me - I'll never sell the car but if I ever did, I am sure there will be people that'll appreciate the K-Jet going as there are not many people that can actually work on them these days and they can be expensive when they go wrong too!

With regards to the original fuel system handling boost - the mosselman kit that I have came from a car with 220K miles on!

 

[Stratman]

Just because millions were spent on design and development doesn't mean they got it right. Off the top of my head a few examples are MB's wiring looms, VW's dual shaft gearbox, VW/Porsche's propshaft centre bearing mount, MB's harmonic balance shaft and camshaft sprockets.

 

[Will]

This is different to the OP's comments on whether it was cheaper and easier. I can't imagine it being either under any circumstances to fabricate a new fuel injection system from scratch, but yes a more modern fuel injection system can be more tunable.

FYI - CIS was used on forced induction cars including the Porsche 930 and Ford Capri Tickford turbo and the injectors used in the OP's car as the same the ones used in the 190E and the 450SEL 6.9. I think they have capacity.

Sure it can be made to work, but there are better options out there these days from a tuning point of view.

Porsche moved to EFI in later cars (993 era on?) and Ford quickly moved onto EFI back in the 80s too.

Nothing wrong with Jetronic but it’s old technology now and when tuning and forced induction are being considered then it makes sense to look at what options are available.

 

[alabbasi]

of my head a few examples are MB's wiring looms

Yeah, that's when MB went to EFI from CIS

Again, my reply was in response to the OP's comment about it being cheaper and easier. There are merits to moving to a more modern EFI system. Cheaper and easier are not two of them

 

[alabbasi]

Sure it can be made to work

"Making it work" is the most difficult part of converting to EFI from CIS.

Let's think this one through: CIS fuel systems function in a completely different way to regular EFI. The EFI systems use an electronic air flow meter to help regulate fuel. There's typically a sensor that talks to a computer that also gets inputs from an 02 sensor to regulate fuel. CIS uses vacuum to meter air, there is no fuel rail, just hard lines that run from the fuel distributor, the intake is designed for brass nozzles and not fuel injectors. All the ECU does in a CIS system is to manage fuel trim. You can disconnect the ECU completely and the car will still run in a default mode.

At a bare minumum, the OP will have to do some extensive modifications to the intake in order to switch to an EFI system from CIS. Build a new fuel rail, build a new wiring harness, select an EFI system, modify the intake (or build a new one). Set up new linkages, select a new air flow meter and run new fuel hoses as the locations change.

Then the OP will have to adapt his turbo system to work with it all of that when it's been designed to work with CIS. This in itself might turn into a thing is the original setup somehow made forced induction work on a system that used vacuum to regulate air flow. That in itself had to require some engineering and I don't expect it to work out of the box on a regular EFI system.

I don't know if the M103 engine was ever sold with EFI in Europe, they were never sold with EFI in the US and I don't know that the M104 bits will swap over. People here do turbo their M104's using the exhaust manifold from an OM603 diesel which bolts right up. If the OP wants to go the EFI route, it might be just easier to sell what he has and buy an M104 EFI engine and an OM603 exhaust. He can then do what's already been done 1000 times instead of trying to invent his own wheel.

 

[DanMorgan]

"Making it work" is the most difficult part of converting to EFI from CIS.

Let's think this one through: CIS fuel systems function in a completely different way to regular EFI. The EFI systems use an electronic air flow meter to help regulate fuel. There's typically a sensor that talks to a computer that also gets inputs from an 02 sensor to regulate fuel. CIS uses vacuum to meter air, there is no fuel rail, just hard lines that run from the fuel distributor, the intake is designed for brass nozzles and not fuel injectors. All the ECU does in a CIS system is to manage fuel trim. You can disconnect the ECU completely and the car will still run in a default mode.

At a bare minumum, the OP will have to do some extensive modifications to the intake in order to switch to an EFI system from CIS. Build a new fuel rail, build a new wiring harness, select an EFI system, modify the intake (or build a new one). Set up new linkages, select a new air flow meter and run new fuel hoses as the locations change.

Then the OP will have to adapt his turbo system to work with it all of that when it's been designed to work with CIS. This in itself might turn into a thing is the original setup somehow made forced induction work on a system that used vacuum to regulate air flow. That in itself had to require some engineering and I don't expect it to work out of the box on a regular EFI system.

I don't know if the M103 engine was ever sold with EFI in Europe, they were never sold with EFI in the US and I don't know that the M104 bits will swap over. People here do turbo their M104's using the exhaust manifold from an OM603 diesel which bolts right up. If the OP wants to go the EFI route, it might be just easier to sell what he has and buy an M104 EFI engine and an OM603 exhaust. He can then do what's already been done 1000 times instead of trying to invent his own wheel.

Hey,

Just to clear a few things - not reinventing the wheel here, there are loads of M103 kits available that can be used but I opted for this one - M103 EFI kit - as it includes higher quality parts and the company fitting it has done it before (they stated apart from a few things, it is very basic/plug and play for them).

Sure you could use the M104 and mess around even more but keeping the M103 as its a 300CE retains somewhat originality. Will be using some parts from the mosselman kit (i.e. manifolds) but not all of it (i.e. intercooler will be different).

K-Jet working is great but when it goes wrong it can be a pain.

I look at it from this point of view, with the modern parts and an ECU that will tell me any error codes, it'll be easier to maintain than a K-Jet. Also, there are not a lot of people that like working with K-Jet stuff and say in 20 years time, there will be even less. With the modern stuff, I will have far less trouble finding someone to work on it if I can't with the error codes and updated parts.

 

[alabbasi]

Hey,

Just to clear a few things - not reinventing the wheel here, there are loads of M103 kits available that can be used but I opted for this one - M103 EFI kit - as it includes higher quality parts and the company fitting it has done it before (they stated apart from a few things, it is very basic/plug and play for them).

Sure you could use the M104 and mess around even more but keeping the M103 as its a 300CE retains somewhat originality. Will be using some parts from the mosselman kit (i.e. manifolds) but not all of it (i.e. intercooler will be different).

K-Jet working is great but when it goes wrong it can be a pain.

I look at it from this point of view, with the modern parts and an ECU that will tell me any error codes, it'll be easier to maintain than a K-Jet. Also, there are not a lot of people that like working with K-Jet stuff and say in 20 years time, there will be even less. With the modern stuff, I will have far less trouble finding someone to work on it if I can't with the error codes and updated parts.

So in looking at their top of the line kit which is 1850 Euros, I don't see where they replace the linkages for the throttle plate but that could be part of the TPS (or not). I also don't see how the will fit the EFI injectors. Remember the CIS injectors are nozzles with a rubber boot and not an o-ring that are clamped down using a bolt and a special bracket that presses them in.

Three questions still come to my mind

1) What exactly was wrong with your CIS injection system that would require 1850 Euro's in parts, a whole lot of labor and possibly some machining?
2) If your turbo kit is designed for a CIS-E system, what kind of adaptions will you need to do there?
3) Are you still thinking that it's cheaper and easier?

In 20 years time, your mechanical system will probably be working as it does today and you'll probably still be able to buy parts for it as Ford, VW, Audi, Porsche, Bentley, Rolls Royce and Mercedes Benz (and maybe some others) all used CIS fuel injection. Getting an updated ECU for your M103 EFI conversion kit will probably be as achievable as getting a new circuit board for a speak and spell that sold in 1983. Probably less because they sold millions of speak and spells.

 

[DanMorgan]

So in looking at their top of the line kit which is 1850 Euros, I don't see where they replace the linkages for the throttle plate but that could be part of the TPS (or not). I also don't see how the will fit the EFI injectors. Remember the CIS injectors are nozzles with a rubber boot and not an o-ring that are clamped down using a bolt and a special bracket that presses them in.

Three questions still come to my mind

1) What exactly was wrong with your CIS injection system that would require 1850 Euro's in parts, a whole lot of labor and possibly some machining?
2) If your turbo kit is designed for a CIS-E system, what kind of adaptions will you need to do there?
3) Are you still thinking that it's cheaper and easier?

In 20 years time, your mechanical system will probably be working as it does today and you'll probably still be able to buy parts for it as Ford, VW, Audi, Porsche, Bentley, Rolls Royce and Mercedes Benz (and maybe some others) all used CIS fuel injection. Getting an updated ECU for your M103 EFI conversion kit will probably be as achievable as getting a new circuit board for a speak and spell that sold in 1983. Probably less because they sold millions of speak and spells.

1) It had never run right and I've replaced all the common parts
2) Using some parts from the Mosselman but bits that were for the stock setup will be replaced with modern alternatives (i.e. a much better intercooler as they are known for getting hot!)
3) Cheaper was probably the wrong terminology I used but I have gone for the best setup out there - Easier for me going forward 100% yes. There is no point going for cheap parts when I want to try and build it to the best I can.

--

hmmm - Sure you'll be able to get parts 20 years on but at what cost? K-Jet and all the fuel distribution parts won't be anywhere near as cheap as they are now and they aren't exactly cheap now for fully refurbed parts. 20 years later, there will also be fewer "old school" mechanics that you will be able to find to install the stuff too.

Have you checked out the main components of the kit - if the ECU decides to s*** itself, big deal I will get another standalone ECU and tuned - MaxxECU is a reputable brand and I am sure they'll be around 20 years+. Most of the other parts are consumables that can be easily picked up too i.e. Bosch injectors & TPS, LS coils etc. Better still, the ECU will provide me with actual diagnostics that'll make maintenance far easier.

I get what you are trying to say but I am futureproofing the car, making it more reliable, easier to work on and "cooler" at the same time. At the end of the day, it's only an M103 - I have a 190 cosworth that'll remain with the K-Jet as the engine is a much rarer item. I also have an R129 SL500 (M119) and a W210 E55 where the engines will remain stock but they don't suffer with the dreaded K-Jet and I can use my STAR with them too.

 

[DanMorgan]

As your dogleg box came from a cosworth it should be the long input shaft version, so you need the older solid flywheel to match. I'm assuming your going to bin the EZL and dizzy and run 6x coils? If you are it wont matter if the flywheel is for a 4 or 6cyl engine, if your keeping the EZL setup you need the proper M103 flywheel.

The gearlever assembly itself is different for a dogleg box, though the 3x linkage rods are the same for any manual w124. The pedal box can come from a 190, w124, w202, and I think w208.

The front section of the propshaft is longer on a manual w124, you will struggle to find that as there are 3 different versions. The front section from a w210 can be made to work in it's place.

The part that everybody forgets is the clutch fluid feed line from the brake reservoir to the clutch master cylinder, it has a plastic push in fitting that can be a pain to get right.

You may need to think about a diff upgrade to a 210mm version, the small diff the 300e has wont last long. That use's shorter drive shafts, but a longer propshaft.

Picked up the Dogleg setup today - thanks for the clutch fluid feed line and cylinder (would've forgot that!).

If anyone is looking for parts, highly recommend Mercedes W124 parts | Fraübenz Classic Mercedes Parts | England (lots of parts on eBay too)

 

[carat 3.6]

Picked up the Dogleg setup today - thanks for the clutch fluid feed line and cylinder (would've forgot that!).

If anyone is looking for parts, highly recommend Mercedes W124 parts | Fraübenz Classic Mercedes Parts | England (lots of parts on eBay too)

Don't forget to check if the 190 propshaft is long enough, you only need to change the front part but it might be too short.

 

[alabbasi]

hmmm - Sure you'll be able to get parts 20 years on but at what cost? K-Jet and all the fuel distribution parts won't be anywhere near as cheap as they are now and they aren't exactly cheap now for fully refurbed parts. 20 years later, there will also be fewer "old school" mechanics that you will be able to find to install the stuff t

To be honest, CIS is not that complicated. I have a 1977 450SEL 6.9, you can still get every fuel injection component for that car 45 years on. Given that the last Mercedes Benz CIS car left the factory in 1992, I see no reason why supply would dry up. I can still get D-jet fuel injectors for my older Mercedes Benz so I doubt that there will be a problem.

Fuel distributors are pretty simple in function, they're basically two halves with a membrane in between. The membranes are available on eBay and rebuild services are available. Aside from cleaning, the only thing that can fail is the membrane. All diagnoses can be done with a fuel pressure gauge and reading the duty cycle from the 02 sensor.

02 sensor, fuel injectors, EHA, fuel distributor, fuel pressure regulator, fuel pump, cold start injector, AAV, and fuel accumulator. What did you replace and what's left?

 

[DanMorgan]

Don't forget to check if the 190 propshaft is long enough, you only need to change the front part but it might be too short.

DM'd you a few questions regarding the conversion

 

[DanMorgan]

In case anyone was interested - this has gone ahead - most of the EFI, dogleg box and clutch is on. Twin turbos and intercooler setup is next on the list as well as a new exhaust system (needs a much bigger diameter for the turbos than my current stainless steel system).

 

[alabbasi]

Looking good, Under no circumstances should you replace the under bonnet insulation. That's got at least another 10 years / 100,000 miles on it.

 

[Will]

Looking good, Under no circumstances should you replace the under bonnet insulation. That's got at least another 10 years / 100,000 miles on it.

Lightweight version, more speed

 

[DanMorgan]

Looking good, Under no circumstances should you replace the under bonnet insulation. That's got at least another 10 years / 100,000 miles on it.

Haha easyyyyy!

A heat shield will be put in its place as it'll get hot under there

 

[optimusprime]

hi
looking for an expert on KE systems myself, air flow plate is sitting low and running rich but no adjustment on the grub screw, needs the plate re-setting...

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