W114 Coupe

[marko]

I just sold my classic 80's diesel and looking at an early 70's 250C

Any tips on what to look out for in terms of known problems of this era model?

[mbbuff]

I am kind of partial, since I have a 280C (see pix in the Registry), but if I did it over I'd still buy the same vehicle. The 280C started in 1973 and has the dual overhead cam, in-line 6 cylinder engine with cast iron headers and a Solex 4 barrel carburator which is a copy of the Rochester Quadrajet. Like most 30-40 year old Benz's, they are relatively trouble free, if well maintained. When neglected they can be real problems. The main area of concern with the drivetrain is the carb. if someone has messed with it and screwed it up. Other than that, the engine, transmission and differential are pretty good. Some of the early Benz's have a slight rear end noise. I've put three different used ones in mine and finally have one that is only slightly quieter than the original, but not annoying.

The 250C is essentially the same as the 280C chassis wise and was made (I think) from 1970-1972. It has the same engine as my 250S (again, see pix in the Registry), which is a single overhead cam, in-line 6 cylinder engine with dual Zenith staged 2 barrel carburators. Again, this is the weak spot, if someone has messed with them. The biggest problem is if someone has gotten them out of syncronization. On both of mine, no one but me has ever messed with them and I have no serious problems with either. I've replaced floats in both, replaced the accelerator pumps in the Zeniths and rebuilt the 4 barrel last year.

Bottom line, when looking, is try to find one that has had reasonable care, and no "shade tree" mechanic has fooled around with. Try to be sure that all of the original equipment is intact....air cleaner, air conditioning (if equipped), interior components, no rust (check rear rocker panels behind the rear wheels), dent free, descent chrome, etc. On either one, be sure the heater blower motor works, and is quiet. They built the cars around these blowers and are a real "PITA" to replace. Check all power windows for up/down operation. They're normally a little slow. Stay away from any 74> 280C that has the "thermal reactor" emission system. It played havoc under the hood due to the heat generated. This system may have only been installed on California vehicles, but I am not sure. Parts for it are also hard to come by and it is a bulky system. Most other vehicle parts are fairly easy to find, and reasonably priced.

I've had my 280C almost 25 years and last year went through almost everything, except engine and transmission, which are still sound at 187,000 miles. I did replace the reverse piston seal in the transmission, because it was slow to engage when cold. I repaired, rebuilt or replaced almost everything else, whether it needed it or not, solely because it hadn't been done since I bought it, and I thought it was time. One other thing, the 2.8 engine is higher revving than the 2.5 and has a fair amount more power. I can cruise all day at 100 mph in the 280C, but the 250S sounds/feels like it being overworked at 65 mph.

Happy hunting, and hope this helps a little in your search.

[marko]

It's my understanding from looking though that the 250 and 280 had different body styles. The 280 looks a little more classy and the 250 looks more sporty. Is that right?

[mbbuff]

Marko, the 250C and the 280C use the same body and chassis. There are a number of cosmetic differences from year to year, but the biggest difference between the two is the engines. Again, having vehicles with each engine, I am partial to the 280C M110 engine. It's the dual overhead cam, 4 bbl. carb'ed engine. In addition to being higher revving, it puts out a little more horsepower. If you find a good one of either model, for a reasonable price, I don't think you can go wrong. If you go a little newer (74-75), you still have the same body/chassis, plus you'll get the 5 mph bumpers (IMO, ugly) and I think in 75 they came out with the 280CE, which is fuel injected instead of carburated.