1966 250S To buy or not to buy???

I am condidering buying a 250S 1966 - body in great shape, a few cosmetic things to do, previous owners UNKNOWN, seller states if he was to do any work on it the exhaust system should be worked on......the transmission shifts fine but seems a little hard on the gearing up....no slipping just a hard change....the driver said that the oil should be changed every 2x of gas being put in......also vehicle seems to like 60-70 mph....not more is there anything here that seems unusual or stay away from or could it be fine? Dont know a MB tech in the area of Walnut Creek Ca to go out and check??

Thanks, Volf

[psfred]

Only 60-70 mph? Should be happy there, but go MUCH faster, even with an automatic.

The automatic will shift HARD by american standards. This is normal unless it is so bad that the driveline bangs. Most likely normal. Worse under hard throttle if you lift your foot, too.

Exhaust is probably shot, they usually are.

Change oil every 3000 miles for "dino" oil, 6000 or 7500 for synthetic. No need to do it more often UNLESS the following:

Probably has warped carbs from stuck heat riser valves. You will need to get them repaired/replaced and rebuild them. If warped (and/or the risers are still stuck), you are dumping fuel down the throats, running WAY too rich, and diluting the oil. VERY common on these cars -- search listings for "Zenith" for more info.

If the body is in good to exellent shape, and it has good oil pressure, all you need to fix is the exhaust (I've had Timevalve stainless steel recommened --$600 from manifold to rear tip -- and plan to get one for my 280 SE soon) and the carbs. Not much else goes wrong.

Make sure the heater blower works, too -- major rebuild required to get to it.

These cars should be appreciating in value, they are getting scarce in good condition.

Peter

[1967250s]

Originally posted by volf
the driver said that the oil should be changed every 2x of gas being put in......also vehicle seems to like 60-70 mph....not more Thanks, Volf

hmmmm....sound's fishy to me ; change the oil every 2 tank!?
If you are going to check this car, bring a miror for the underbody or any hard to see places and if you can, lift the carpets.
Better yet go on a rainy day and check for seal leaks.
Look at the bumpers and grill carefuly sometime the chrome is there and the metal is not.
I was going to sell mine for lack of shade to work on it, now that winter is here and the beauty is under wraps (finaly) I'll be giving "the monster project" a second chance when sping comes.
The beast kined of grown on me. The W108/109 are nice looking sedans.

Good luck

DAN

The 66 250S is a great car.. I got mine new..I sold mine to a fellow in Hayward a couple years ago...

About the trans.. It was the first that Mercedes built.. It has no converter.. Its a lock up clutch... On the front carb there is a small switch with some thing like points in it.. when you are at an idle it opens the clutch so it will idle at a stop.. when you step on it and it gets to 800 to 900 rpm the clutch closes and all shifts after that are made with the clutch locked up.. An early version of the luck up clutch that americans invented in the 80s.. (Ya right).. With the small engine Mercedes did not want to loose power thru the converter like they had been doing with the Warner transissions that they had been using..

The old 250 single cam engine was a hold over from the early days of trying to make the engine last for ever some thing that both RR and Mercedes were doing from the 30's . They burned oil.. Lots of oil.. right from the factory.. the blow by in the engines blew lots of oil thru the vent in the valve cover over to the carbs and the engines were set up loose with almost no.. or no valve guide seals.. So the whole thing was kind of a controled leak to the carbs where it was sent into the pistons and lubed every thing including the valves ... At speed.. 100 plus mph it was common to burn a gallon per thousand miles in those old things.. and around town a quart every other tank of gas... Those old engines are still running with hundreds of thousands of miles on them and when you tear one down it showes little wear..

These smoking engines did not go over well here and were only brought in a couple years.. then they redesigned the engine and put a 250 in the 114 cars.. However it was not the same engine that was in the 250S cars of 66 and 67..

Great car.. for its size it is a very light car.. and loves to cruise at speed.. I pulled a trailer with mine for years hauling a couple motorcycles.. Took it all over north america.. But finding some one to work on it if you do not, will be a problem as most do not under stand the twin carbs with switches the run the clutch on the automatic trans.. and every one wants to over haul it because it burns oil... Like it did when new..

If you do your own work it is a great car to own.. and one of the best looking cars Mercedes ever built..

Snowdance

[joshhol]

The old 250 single cam engine was a hold over from the early days of trying to make the engine last for ever some thing that both RR and Mercedes were doing from the 30's . They burned oil.. Lots of oil.. right from the factory

Was this engine the extension of the M180 used in the Fintails?
Or was it a different design?
The M180 in my 220S has very different characteristics from the ones you described in the 250.

[Mark DiSilvestro]

My '60 220S smokes when first started, then the smoke quickly subsides. I get a lot of oil dilution, especially in colder weather so I try to get off the choke ASAP. I've been changing oil at less than 1500 mile intervals. Oil is cheap and I'm trying to get this 42 year old engine to last awhile. It still has good oil pressure and runs almost perfectly, although I think I'm hearing some piston slap when its cold.

Happy Motoring, Mark

[240 Ed]

Volff

You are getting some sound advice here. fortunately we don't have too much rust to worry about, but they were fairly fragile about rust.

I have a 68 250S (Gina), and love it very much. It came with a rebuilt engine, so it runs without smoke. fussed with the carbs and it runs as new! The idle jets were clogged.

There used to many of these cars around until *******s started buying them and shipping them off to Germany! When was the last time you saw an old english sports car running around? Same *******s. Didn't care about cars, just out to make a buck.

So if you find an old car, hold on to it! We are the new custodians.

If you get the car, I would be glad to look at it-I have gotten pretty good at diagnosing these vehicles.

I am not real sure when the change came in the engines but the first one I knew of was the change between my 250S and the other 250 in the 114 or 115.. The big change was the fact that the engine deck.. (Part you put the head on) on the old engine was solid.. The new engine had a cut out deck.. Cut about the Cyl so that they stayed more round.. The old solid deck when it warmed would make the Cyl. egg shape.. So they started to cut about the Cyl.. to releave the pressures caused by the block metal expanding.. so the Cyl. Stood alone and stayed more round... Most engines are that way today..

Also along about that time some one figured out if you make a round piston and heat it.. it becomes egg shape.. More metal here ...less there.. = egg shape... So they started making egg shape pistons and when they are warm they are round.. and Rings are now hold their shape and spring far better.. So now using oil is not as common as it was..

Most of the old solid deck engines that are rebuilt and get new pistions get the new style pistons and rings that keep their spring and better valve seals that do not get brittle in a short while.. All making for far less oil use at speed..

Ken

[hippie_elmo]

I see that you live in Walnut Creek,CA. That is were I live. I know a very good MB tech in Walnut Creek. He is in the downtown area. If you want his phone and address let me know.

[joshhol]

Most of the old solid deck engines that are rebuilt and get new pistions get the new style pistons and rings that keep their spring and better valve seals that do not get brittle in a short while.. All making for far less oil use at speed..

Ken-
That would probably explain it, my M180 was rebuilt in '83 according to the records that I Do have.
So I guess that means the engine in the fintail has the solid deck design. I'll have to keep an eye out for that if I get a chance.
(I'd rather not see it anytime soon)

Oil is cheap and I'm trying to get this 42 year old engine to last awhile.

Mark you have the original engine!?! That's neat!
My 220S has about 150,000 on it's engine (by my estimate of incomplete records) and acts the same way as yours. Smokes a little on start up, oil pressure is Always way up and does make sound at start up I don't like. (Sounds like something metallic, then is gone right away ((perhaps the sound a bearing might make if dry?????))
Besides that, it runs like a B-Yatch!!

[Mark DiSilvestro]

Joshhol,
'Miss Daisy', my 220S had many repairs done by the original owner so mechanically, it's in pretty good shape. Since I acquired the car, last year, I had to replace the motor mounts and 1 brake hose, (also fitted front lap and shoulder belts - a major project!) Unfortunately, the original owner kept the car outside so it's rusty. It's not too bad after 42 years but it's a driver, not a show car. I'm not sure how religious she was about oil changes and the speedometer was replaced many years ago. I still have the original one and adding up all the mileages, I figure it's almost 200,000 now. There's kind of a throbby, muffled clatter above idle, when accelerating, that diminishes as the engine warms up (Maybe those 'egg shaped' pistons!). My first Mercedes, a '61 180b, made similar noises for many years, without exploding, so I'm going to drive and enjoy 'Miss Daisy' for as long as I can.

Happy Motoring, Mark

[joshhol]

Hey Mark,
Sounds good.
I have the shoulder only (decapitation) belts. I may have to find out from you how you added those lap belts sometime.
Sometimes I think that if I wrecked that car, I wouldn't want to see it anyways but that is too dark to think about.
Based on my sketchy records, I think mine has 432,000 miles on the car. 150 on the engine. It was very well taken care of by the original owners, I think it was special to them, they bought it on their honeymoon in Germany. So, it has the European headlights which makes people look at in awe and wonderment.
It's Graphite grey, repainted sometime, and pretty well done. Although it seems like thin layers of paint compared to my MB paint job on my 300D. The interior is awesome too. The original leather seats were replaced with vinyl, which actually is a blessing. It has a sunroof and 4 spd column shifter.
It's so nice I worry when I drive it. California drivers are so impatient it makes me cringe. I pick and choose when I take it out of the garage.
There is a little bit of rust. It is my mission to neutralize as much as I can before that car leaves my hands. Hopefully that won't be soon.
Do you have any pics of yours? I don't know how to post mine cause they're not in JPG form and I don't know how to convert them.
I does have a repair list: Speedo sounds like an old crank siren, shifter isn't drum tight, clutch chatters sometimes, repetetive ticking sound coming from rear axle, carbs leaky.
I replaced the exhaust (OEM) and rebuilt the brake booster.
I was lucky. When I bought it, the guy said it had been rebuilt recently. One weekend I was driving all over creation with no problems. Next day, backing out of the garage, No Brakes. Pulled E-brake, no problem. Car sat for 6 months.
Now it sits again cause I'm worried there is a problem with the speedo itself. I hope it's the cable intsead. I just pulled the cluster to swap out the fuel gauge with the junkyard score.
After hearing noise, saw new wear marks on the cable end that goes into the speedo.
Oh well, one step forward, one step back.
Good Motoring!
Josh

[Mark DiSilvestro]

Joshhol,
By the early '60s, cars sold in Sweden were required to have shoulder belts. Saabs had the shoulder belts only, while Volvo introduced the combination lap and shoulder belts. In 1963, lap belt anchors were required for cars sold in the US, then the lap belts in 1964, finally, front shoulder belts were required by 1968.
20 years ago, my dad had a '66 250SE, Euro model with the factory 'Kangol' shoulder belts in front, but strangely, no lap belts. My '60 220S had no belts or factory anchor point at all. My major project was to design and fabricate inserts for the door pillars to attach the shoulder straps. Adding just lap belts to your front seats could be relatively easy. Your '63 220 may already have factory anchor points for the lap belts. One of the lap belt anchors would be the bottom shoulder belt anchor. Otherwise, if your floors behind the seats are sound, you could bolt the anchors there. I decided to mount my 220S floor anchors in the side of the tunnel and the inside door sill, like the factory mountings in my '72 250 sedan and because my 220 floors are somewhat rusty. I originally considered finding suitable belts in a salvage yard but didn't want to trust used belts. I ordered new combination lap and shoulder belts from J C Whitney. They are non-retracting and come with the old style chrome buckles, like what would have been availible in the early '60s.

As to your speedometer, the cable may not be the problem. I've had good luck lubricating the bushing, at the rear of the unit where the shaft sticks out, with automatic trans fluid. I lubed my 250 speedo this way, when it started howling 12 years ago and it's been quiet ever since. Lube the end of the cable too, while you're at it.

As for clutch chattering, mine does that too.
According to some old road tests I have, some of these cars did this even when they were new!
For me it's a minor problem and it runs so well otherwise.


Happy Motoring, Mark

[joshhol]

Mark
Thanks very much for the advice!
I'll let you know how it turns out.

One of the lap belt anchors would be the bottom shoulder belt anchor.

The shoulder belt anchors at the top of the pillar on mine.
I think the inside door sill would be the place to anchor the lap belt. The shoulder belt catch is anchored to the tunnel, so If I could get a combo belt from JC, I would only have to bolt into the door sill.
Did you put any in back? I'm sure that's fairly easy to figure out.

Thanks in advance!
Josh

[Mark DiSilvestro]

Josh,
As these cars were sold all over the planet, your '63 220 may already have a factory installed anchor/threaded hole in the door sill, for the lap belt. You may have to peel up the rubber matting to find out. My outer rockers were already rusty so it was a no-brainer to insert the backing plate through a rust hole then cut a small access hole to insert the socket / nut for the belt anchor. If your rockers are still intact and there's no factory anchor, you'll need to decide where to cut an access hole. Maybe further back on the inner sill so as to not weaken the area where you'll be drilling the anchor hole, The access hole could then be hidden by the rubber matting. Then, you could fish the plate and nut into place with some stiff wire or coathanger. By the way, the international standard for the belt anchor bolts and threads is 7/16 fine thread, not metric. I've been told this standard was chosen due to seat belts being originally insalled in aircraft. I checked during my trip to the salvage yard and it was the same in the American, German, Japanese, British and Swedish cars I looked at.

I very rarely have back seat passengers.
I haven't decided if I should just install lap belts or go with another set of lap and shoulder belts so there aren't any belts in the rear yet.

Happy Motoring, Mark