First time I bought an engine sight unseen, but the offer was too good to pass up on. But I'm sure this project will be behind schedule and over budget once again.

What is the project?

And I’m not too familiar with merc stuff, is that that diesel, or petrol with mechanical fuel injection?

How is that fan balanced at all! It's got to be some perspective thing, right?

EDIT: well, I'm impressed! Learned a bunch!

I hope your eternal project car is a hoopty-ass shitsmobile otherwise you’re in for a bad time.

It's the 2.3L M102 Petrol for a 1991 W124 230E. It does have a extremely convoluted electronic fuel injection system basically just slapped on top of the mechanical injection of the previous generation. It's a nightmare to diagnose if something goes wrong but you can run the car without the ECU and it will just revert to the mechanical injection.

A lot of older engine fans are like that. I've been told it has something to do with wind noise. Other people have said it's for ease of access during assembly. Not sure which one it is, maybe both.

Depends how you look at it. The car is pretty mechanically sound aside from the fact that this is engine number 4. I probably never should've bought it but I'm committed to bring it back from the dead once again.

KE-Jetronic? Fun things those

Yes! If it works it can really run great. But that's a big if :D

Yeah, no, fuck that. It's a project car anyway, get EFI on that thing if you can afford it.

KE-Jetronic is one of those things where you tell people about your troubles and they're like "there's a guy in that other city that can fix it"

It's one of those things where, for 15 years, there was a company dedicated to replacing it on inline 5 Audis.

And if the likes of Haltech, Megasquirt, Maxxecu are expensive for you (hey, I understand, they're pretty expensive), I may know of a future solution that will be significantly cheaper, but I can't write it out here without sorta doxxing myself. It will involve custom wiring and stuff of course. It will involve scrapyard parts and possibly some new ones, nothing to purchase from the guy behind the project, he'll just be happy to have a pre-alpha tester lmao

It is very hard and expensive do covert an old car to a modern EFI system where I live. Not the technical side, but registering it to be legal on the road can be a major hurdle. This car was running smooth as butter until the engine died due to mechanical failure, so I will be keeping the KE for the time being. I do in fact have a complete kit in storage from the Ukrainian company invent-labs.com, but it's really just there as a backup plan. I appreciate the suggestions though and I'd love to hear about that future solution if you're willing to shoot me a PM!

Not the technical side, but registering it to be legal on the road can be a major hurdle.

That's weird. If an old car still has to meet emissions for some reason then the ol' tailpipe sniffer ought to work just as well with aftermarket EFI as it did without it, and since you'd likely be improving the emissions by converting it there shouldn't be much for regulators to reasonably complain about.

I'm not saying I don't believe you; I'm just saying that's dumb on the regulator's part.

Seems OP is in Germany, where any and all safety or emissions related modifications to a car need to be certified. You can't legally do custom exhausts, brakes or I believe even a cold air intake unless it's TÜV certified.

Oh I agree 100%. In Germany we have extremely strict (and sometimes ridiculous) rules when it comes to cars and modifying them. The system basically allows modifications only with parts that are officially approved for the specific model of car. Most aftermarket stuff comes with a pre-approved technical component report, so you just need to hand it to the inspector and they will register it to your car for like 50 Euros. If a part doesn't have a report, you can have the inspection service make one, but, depending on the part, this can be very expensive. If you're lucky, someone else has already done the modification before and a custom report exists which you can use.

In case with EFI systems you will most likely not be able to use a existing report because the tune is always different. So you'll have to get one made just for the tune your car is running on, which again, is very expensive and a major hassle.

Shot you a PM.

On the keeping Jetronic side, I guess if your car already had Jetronic and you know it runs fine, it's fine. Something I remember hearing back when I had my Jetronic (which did, in fact, not run perfectly - hot idle stalled when going off power and hot starts took 10 seconds of cranking while everything other than was perfect) was that if you let the fuel distributor thing or whatever go dry, that's often where problems start. I don't remember exactly, that was a decade ago. Mine was an inline 5 Audi though, there may be parts that are different.

Funnily enough, my hot start issue was defeated by disconnecting the coolant temperature sensor. But when I replaced it with a new one, it had issues again. I just kept it connected and put up with the long cranking as I figured it might run too rich without said sensor and waste a ton of fuel

Huh, neat.

I think being plastic it's not very heavy, and there's probably counterweights in the hub of the fan for balance.

I'm pretty sure they're made this way for access to the very bolts that tension everything, since you can't take the fan off until tension is released, as it's part of the water pump pulley assembly.

(You possibly can remove it, but often those bolts are too long to remove with the radiator in place).

That's is just messed up. Hahaha, wow.

Huh, I actually think I know what was wrong with your Audi because I had the exact same issue with my W124 before. It's probably the fuel pressure regulator. When it goes bad it will cause vapor lock in the fuel lines under the hood after the car has been driven. The lines are no longer holding the pressure so the petrol turns to gas. When you disconnect the temperature sensor you're overcoming the vapor lock faster by increasing the amount of fuel the distributor puts out. Otherwise you will be cranking for 10 seconds or more.

May the cylinders be clean and the rods straight. Car gods, bless this engine, so that Hubi need no rebuilds, and thine Merc be returned to former glory, as the Germans intended. Carmen.

Beautifully said, thank you 🙏🥹

Ha, nice. I'll take note if I ever buy another one. That said, mine was on the less problematic end of the spectrum. The part I always heard horror stories about was the fuel distributor and this is in a country where DIY mechanics are literally everywhere because of a large subculture of people with little money and expensive taste in German cars. I have no idea if online resources on the KE-Jet have gotten any better over the last decade or so though, might be that there's actually guides on how to rebuild the fuel distributor nowadays lol. Plus I guess over the years I've worked on a bunch of delicate and/or complex systems. I'd be more afraid of paint work than a full engine or automatic transmission rebuild lol

It breaks up the buffeting, and reduces the harmonic peaks

Okay, what the hell happened to engines 1-3?

Engine #1 died because the previous owner had a major accident in 2004 that shattered the oil pan and tore off the front suspension. It was replaced with a remanufactured engine. The car mostly just sat for the next 15 years and engine #2 barely had 40k km on it. Not sure what they did to it, but it had rod knock when I bought the car. It subsequently grenaded on the highway. I just wanted to get it back on the road ASAP and got engine #3 from some guy's backyard for 100 bucks. It wasn't really worth putting a lot of money in, so I just slapped on new bearings on and put it in the car. Surprisingly it lasted for 5 years of daily driving but now it lost compression on cylinder 2.

I will be taking my time with engine #4 though, this one will actually turn out nice and I don't plan on replacing it ever again.