Gather around, boys and girls and Uncle Ivan will tell you a story. It starts with a loud noise from the front of the car as I was driving about 60 mph. Within seconds, the lack of power steering and red low voltage warning informed me that it wasn't a rock or something else I had ran over, but it was sound of an idler pulley or tensioner falling down on the job. It's a 15 year old E class and even with less than 70k miles on it, so these things are expected to some degree. I could have handled limping it home without power steering, but with no belt driving the water pump, I had to lean on AAA to tow the beast home.

So once home I opened the hood to find this, as expected:


Pretty much what I expected. A large chunk of the idler pulley MIA. So I inspect the area, find some random pieces of the pulley in the engine compartment but when I tug on what is left the part still attached to the car, the bolt holding the pulley in place slides freely in and out of the hole. Okay, the bolt broke. And I didn't have to look at the bolt too long to decide it needed to go to my mechanic. If it was just a matter of pulling the water pump and removing the bold sticking out of the timing cover, I could handle that myself. But I could tell by the length of the bolt that it was broken off well inside the hole in the cover so this was beyond my tools on hand and skillset, since if I botched this, well, removing a timing cover wasn't something I wanted to get near.

So it goes to the shop and after a couple days, it's ready. But my mechanic wanted me to see something when I arrived to pick up the car. Look at that little thing that looks like a cap sitting atop the part of the water pump that where the bolt goes thru to hold the idler pulley. What could that be? Was it some new feature of an aftermarket pump?



No, not a new feature designed into the Mercedes water pump. The next picture is of the water pump from the other side of where that "cap" was located:



See that thing that kind of looks like a spike sticking out of that side of the hole? Well it looks like a spike because that's exactly what it is! Apparently, one of the previous owners had this bolt break on them a year or 2 ago and confronted with the prospect of having to extract the broken part out of the timing cover, decided to shove the new pulley and bolt back in there, then drilled a hole through the housing and shoved that spike in there to hold the bolt in place! You can see the broken bolt with a notch cut out of it where the spike was holding it until it broke.

I'll give the guy points for creativity on a hack repair.

 

The m112/m113 all aluminum engine can cover quite a distance without any coolant flown. Limped my C320 home on the freeway about 10 miles with a shut thermostat. Coolant temp didn't exceed 105c at low power. Abient temp was in the 90s. The aluminum block and heads can dissapate a lot of heat directly to the air.

 

On a positive note, you are replacing the pulley, water pump, and belt at the least. It was coming up to be replaced anyways, just came a bit sooner and unexpectedly. Glad it worked out. I bet now you are wondering what other creative engineering the previous owner has done!

 

This has indeed given me a moment of pause. Just when you think you've seen it all.....

 

Wow.... backyard hack level i would call that a 10 LOL

 

To this day I still wonder why people do half assed ****.... really, I can't fathom. My wife always say I over engineer or make things bullet proof.. IE: If I am working on one thing then everything around it gets replaced if it's around or close to the maintenance cycle.. since I am there already. Good measure right... but I can't understand why people do the above and then think that's acceptable.

Lucky for the OP it wasn't worse. And as another has pointed out you are replacing that stuff which is good. Could have definitely been worse.

-Nigel

 

I hear ya Nigel, I do the same.... I used to run Audi's... 60k timing belt always include a water pump....