Buying a 240D - What Year?
 

Hi all. I'm a relatively new Diesel Merc guy. I just picked up a 1984 300CD and I'm going to start learning/restoring. I was thinking about a 240D 4-Speed. I've read all the posts about what to look for when buying one and about the advantages/disadvantages between one and a 300/300 Turbo.

I had one question I couldn't find an answer to: What year did Mercedes change the glow-plugs from the loop-style to the pin-type on the 240D? Some 240Ds work with the pin-type, but older ones work with the loop-style. What year did this change happen? Also, was there an associate change in the engine itself? Do some years have more power than others? What year should I go with?

Thanks in advance.

Assuming that you are talking about 123 models, 1977 to 1983, these are all old cars, finding a clean, rust free model should be your prime consideration.
I have a 77 manual, the early models were fitted with York A/C compressors, I would avoid the early models just for this reason alone.

Vahe
240D 77 350K

I believe better rust protection started with the 123's in 77. If you're looking for a 4 season car in a rusting climate, keep that in mind. The 115's look better to my eye tho. Look under floor mats, under the spare tire, look for plugged weepholes in the body, thunk the body here and there, shun the crunch.

My 77 parts car, I just discovered, only has holes in the frame to jack the rear of the car to change a tire with the provided jack. Oddly inconvenient, I must say.

The Kent Bergsma at the puported 'source of mercedes' has a 123 pre-purchase checklist or 'sourcelet' as they call them. I don't know that one, but I have found others thourough (61x valve guide seals, 61x front crank seal, 61x diagnostics) , a little expensive, flirting with smug. If you look at it as spending $20 on not getting screwed, and also a way to generate a hit list to bargain down your purchase price, I'd go for it, especially if I didn't know boo. It reminds me of the out of place feeling I get when I walk into the mercedes parts counter / waiting lounge in a greasy fleece & stained carharts.

Thanks, guys. Vahe, yes, I'm talking about 123s exclusively. I agree, finding a rust-free car is #1 priority. But I thought there was a change in the glow plug system in 1981 as well as an up in power (as well as the a/c system change you mention)? Does your '77 use loop-style or pin-type plugs?

Moon, I agree, the 115 looks much cooler, but don't want to go that old. Thanks again.

My 77 was converted from loops by the P/O. Not a hard fix from what I hear.

You can upgrade the GPs if you want to. I think Phil sells the kit...not too expensive.

Like others have said, I think the overall condition should be your first consideration, Climate control maybe second (first for those of us in more southern locales :D ), then other more cosmetic concerns (color, wheel style, sunroof, etc....)

Unless you're looking for a project, heed engine red flags like an air cleaner full of oil. Test the CCU (hot heat, cold AC, blower function). Run away from the smell of glycol or condensation on the window when you turn on the heat (bad heater core). Nail them down on oil use, get an amount used per oil change. Vague answers or 'well they all use that much at this age' are not good.

Prior WVO use/conversion is a controversial topic. For my $.02 I think damage or lack thereof depends on the individual greaser.

Got it. Thanks, guys. I know you can convert the plugs. It doesn't sound like a big project. I'm still curious about whether or not Mercedes changed the design at any point. I remember reading somewhere that the 240's with the new plugs also put out more power, which is a consideration for me.

My '82 had the newer plugs.

That's what I'm getting at. Thanks, toomany. Here's what I found on Wikipedia:

"The OM616/617 engine received a mild update in 1981. Updates included: new pistons cast with a "star shape" top, revised prechambers for the indirect injection,and more efficient glow plugs. The 240D was last imported to North America in 1983 by MBUSA while production continued until 1985."

I'm guessing "more efficient" refers to the plug-type as opposed to the loop-type. Still not sure about the 1981's though. Anyone have a definitive answer on this, please chime in.

Thanks, all.

The 'more power' had nothing to do with the glow plugs and has been mentioned they can be upgraded in a straight forward manner. It is not much more power so the condition of the engine should be more important than the exact variation.

I suggest a 1980 240d ( or very very close... just make sure it has the TYPE ONE AIR CONDITIONER )....remember that changes were made according to vin number during the year....so you might catch the last of a year not listed as having what you want.. so do not assume if a car is close...go look or have them send you a picture of the dash and the firewall with regards to the type one AC...

You can change out engines, rebuild engines, etc....but if you start with the type one ac unit you will be way ahead of the game for service , parts, and the ability to get it cool and keep it cool. The diagnostic section of the Factory Shop Manual JUST for the push button dash control unit ( vertical wheel type 2 and 3) runs about 80 ( EIGHTY ) pages..... think about that... it is one of the main reasons I sold my 81 wagon...

X2 General condition of the vehicle - interior and exterior is VERY important. Post purchase, your major expenses are going to be cosmetic.

Also, 240D engines - good ones - are rare in my opinion. If you find a good one, you should probably buy the car if the price is reasonable.

Thanks for the great info, leathermang. So if there's a vertical wheel, it's a type 2 or type 3? As long as it's the version with the three knobs, I'm OK (i.e., it's version 1)??

My '79 had loop style plugs, my '83 has pin type. I don't think they are interchangeable as the plug bore (and plug) for the loop style was larger- unless there is some kind of "adapter" I'm not aware of. The engine went from 62 HP (1977 to 1980) to 67 HP (1981-1983) I don't think there is any real noticeable difference between the two though.

The most important things in choosing a car is maintenance history and lack of rust EVER. Cars that have had rust repairs (even though they look good after a repaint) are doomed to have a recurrence. I chased rust in my '79 for years before I finally gave up. If you want a really pristine example, be prepared to pay up.

J.G.

I am pretty sure on that ...... Except you have to check..
I ran across one lately that appeared to have the wheel..
but was clearly the correct one under the hood....
it will just have a little valve and a couple of hoses...
as compared to that huge box at the front of the engine with all sorts of electronics and hoses inside it.... might be referred to something chrysler ?
.... but you are safe if there is only the knobs and the small valve at the firewall....