Sorry to hear about your luck on this one. I thought you were asking for the size of die on a flare nut tool to build new steel lines and thread type/pitch for some reason. I see now, you just wanted the size of wrench for the fittings. All the Mercs I've encountered so far (w126, w123) chassis have what Vstech says... 14mm on the hose and 11mm on the steel line.

I found some hoses originally at a small shop that did work on German imports. I used to get all my parts from him....great guys...gave me lots of advice on various repairs. I paid 90 dollars for the set of 2 until I found out (from here) I could get them way cheaper, so I took the expensive ones back and got a refund to get my set of 4 cheaper ones with change to spare. I paid 45 bucks for all 4 hoses. The 90 dollar set/2 from the Mercedes mechanic were Beck Arnley... took them back and got Beck Arnley from Acklands for 22 bucks/set.

If you type in those part numbers I gave you....those hoses are listed for many...many different Mercedes cars. I find it hard to believe they can't get those hoses in stock where you are compared to the lowly populated sh**hole where I am at. Aside from the small mechanic shop, I got one new set from Acklands and they were in stock. The other set had to come from a city in the next province but I had them the next day.

What would happen if you asked the suppliers for the part numbers instead of giving them your specific vehicle information? Perhaps they have them for another year/model but their software does'nt cross-reference?