I'd imagine if the fan clutch had issues, you'd have more overheating problems at low speed rather than high speed (when air is moving through the radiator very fast). Have you looked at the fan when the engine is running hot at low and high RPMs?

The radiators in these cars are quite old and probably don't work as well as they did when they were new. Your radiator might just have enough gunk in the tubes that boiling it out can't save it. If running a flushing agent in it for a few days of driving doesn't help, it may be time for a re-core or replacement (re-core highly recommended if you plan on running A/C in the car).

If you can get your radiator to cool enough to keep the temperature 20 degrees F or less above the thermostat in high-speed driving, then it should be enough to run safely without A/C.

Speaking of running finnies on the interstate, I got to drive mine (a gray-market 1968 W110 230) on a 1,500 mile trip last week as part of a move. Interestingly, the trip intersected Virginia Beach, and I got to drive it on the Chesapeake Bay Bridge & Tunnel as well as I-264 and 64. I discovered only one problem on the trip, and that was vapor lock (likely due to driving over 120 km/h for hours in the hot weather). I will probably put an electric booster pump near the gas tank to ward it off in the future.

That's what I'm thinking about the fan clutch, probably a waste of time to refill the old one but I'll still do it lol. I think I might try to straighten the fins out, a lot of them are squished, and see if that makes a difference. The guy that cleaned and rodded it out said it flowed good, and when I replaced the water pump the interior passages in the head looked super clean from what I could see. Unfortunately I do agree that it might need to be recored, I asked about that when I had it cleaned and it was going to be about 350$.
I do plan on putting a/c in the car, I already priced out a new under dash unit, parallel flow condensor and all the bits and pieces that go in between.

That's awesome about the highway trip in the finny. I think some of the issue may be with the stock fuel line routing. Goes up by the radiator in front of the valve cover, which to me seems weird because of the heat soak during the summer. I guess it doesn't get as hot in Germany lol. I know when we lived there in the 90s our house didn't have A/C.

So my last post was July of 2018, over 2 years ago lol. I still have the Fintail, and actually for the last few months it has been my daily driver after I sold my E320 wagon (never ever EVER buy a w211 anything). I attached a picture so yall can see my wagon in its natural habitat. Broken. Between conductor plate problems, airmatic problems, 4matic problems, 3 sets of engine mounts, electrical gremlins and dead fuel pumps i have to say it was the most unreliable car i have ever owned. That's saying something because I've owned a lot of British cars.


Well back to the Fintail, first thing i decided to do was to replace the gas tank. I kept sucking garbage up into the carbs and the fuel pump. I didn't want to deal with cleaning and recoating the inside of the old tank so I bought a replacement tank for a W108 Mercedes from this place in the UK call 911design. DHL shipped it to my door in less than a week. The new tank is 82L or almost 22 gallons. The stock W110 tank is 65L or 17 gallons. With a full tank this only adds about 30 pounds to the back of the car so I didn't expect any suspension sagging. The fuel tank structural area is similar on the W110, W111, W112, W108 and W109 so the tanks are interchangeable. It bolted right in.

At the same time i replaced my non functioning fuel level sender with an aftermarket GM 0-30 ohm unit. I didn't feel like shelling out 250$ for a replacement Mercedes one so i adapted an after market. The low fuel level light even works, only issue is that the gauge reads backwards. Down the road I intend to replace this with an OE sender. I also found out that autoparts stores around me don't stock old school inline fuel filters so i went to the hardware store and bought one for a tractor.

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"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

This is how she sits today. Ill continue to post and update on the other repairs/rebuilds I have accomplished.

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

So last post here in 2018 I was fighting overheating, but only at speed. It got worse the longer I drove the car. I replace the fan clutch, replaced the water pump, flushed everything, and replaced the thermostat. I knew what I needed to do so I ended up biting the bullet and pulling the radiator for it to be re-cored. Not sure what I paid the guy to do up near DC, it was definitely not rodded out or cleaned at all, pretty sure all he did was stop one of the rows from leaking. It was disgusting inside, no wonder I had an over heating problem it could flow anything!!

Its getting harder these days to find a radiator repair shop. I was fortunate that I found an old one here in VA Beach that is still in operation. I took it to them and they recommended a 3 row dimpled core so that's what i went with. The dimples in the rows are supposed to slow the flow of the water as it flows through the radiator. Its used in racing applications. If I remember correctly it was around 375$ all said and done. While it was out i cleaned the front of the engine and put POR15 on some areas in the radiator well that had surface rust forming. Put it in, filled with 50/50 Mercedes coolant and bled the system and its been rock solid.

However i have noticed that my head gasket is starting to weep on the driver side of the engine just above the heater outlet. Ill see how long she holds but there probably is a valve job, chain guide and head gasket replacement in my future.

Oh and incase you forgot to never buy a w211 here is a picture of us towing it home after the fuel pumps died.

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

Looks like you are doing the 230 right! It is a handsome car, and fairly quick in its day. My brother had one back then.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

It is surprisingly quick for what it is. It does have the highest output carbureted engine put in a fintail at 125hp. Nothing beats the sound of that straight six at redline, although i dont drive it like that too often.

__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

Wow, that core looks clogged .

I had one like that in my '82 240D and was able to clean it with the citric acid flush, it took a long time of driving it to work and home again daily and replacing the citric /distilled water every time it turned black and thick...

I always try to add more rows when I re core a radiator, not many places do that anymore .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

I replaced my mirror glass, it was pretty bad. Got it from Mercedes. They still sell the spring and the retainer also but i didn't get them. Its very simple, you just pull the retainer out carefully with a small flat head screwdriver, then everything falls out. Install is reverse.

Right after I bought the car i procured a NOS w114 muffler from craigslist. I knew that eventually I would need to replace the existing one because it was extremely rusty. Well it got so bad that the muffler literally broke in half and all the insides fell out so i had my NOS muffler and a tip for a w108 (i think) put on at a local muffler shop. I think it was around 225$ all in. The mid pipe is very rusted and the guy had a hard time welding to it, so it does have a very small exhaust leak there. I put a wrap on the weld from autozone. Eventually I want to get a down pipe from time valve. At this time though I will live with the small leak sound instead of diving into exhaust bolts that haven't been touched in 52 years.

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

Well way back at the beginning of this when I got the car I rebuilt the weber carbs that were on it. At first I was unaware that they were not original lol. I quickly figured that out. After fiddling with them for 2 years and the car not running right and getting poor gas mileage or the idle not being steady I decided to source some replacement originals. Everything I read online said that the Zeniths were horrible carbs and hard to rebuild and were always warped and had vacuum leaks and accelerator pump problems and on and on and on. So what did i do? I bought a used set off a 1970 250S lol. Well I later determined it was a 1970 250S because of the jetting that is in them. Some of the jets and air correctors are available from this place called Ruddies in Berlin Germany. They also have visual breakdowns of all the Zenith's parts, internal and external and speak decent English which is helpful. The second picture is how I got them, a little crusty but still moveable, nothing froze up.

Now I do have to say that these carbs are !NOT! your typical 2 barrel American carb for domestic market. The early versions (pre 1972 emissions crap) have fuel bowl vent valves that vent fuel outside the carb when the engine is off, helps with hot starts (these valves are adjustable and are NLA) the forward carb has a fuel return diaphragm that sends fuel back to the tank when the engine is below 2200RPM (this is adjustable and the valve is available from the UK, later Zeniths used a metering hole instead of the diaphragm) they have a 2 step fast idle, vacuum secondaries which are adjustable, vacuum throttle control which is adjustable (which is a pain to set up right I finally figured it out after 6 months) they have an adjustable accelerator pump piston that wears a leather cup, and the spray angle in the carb throat for the accelerator pump is adjustable. The later zeniths have a warmup circuit. Mine have Idle solenoids and electric chokes (you guessed it, they have to be adjusted). They have separate main and secondary jets, air correctors and emulsion tubes, idle transition jet, idle jet, and a "jet" for the accelerator pump volume. Its completely nuts. I read somewhere that a well adjusted Zenith on one of these cars functioned just as well if not better than the mechanical fuel injection. In the dead of winter i can get in the car, pump the pedal once, it fires right up first time and I can immediately drop her in reverse and back out of the garage and drive away.

Oh and cars equipped with a automatic K4A trans with the 3 position solenoid have a special bottom plate on the front carb. It has an idle switch built into for the trans (its adjustable lol) I finally found one after looking for a year. They sell on parts websites (just the switch) for like 1200$.

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

The reason these guys get a bad wrap for warping is because typically the owner puts the air cleaner on too tight, which warps the top plate. The top plate, jet block and bowl section are aluminum and the bottom plate is steel. Over time this can lead to complications especially if the exhaust manifold heaters are stuck on. My top plate was warped on both carbs. I took some 220 grit sand paper with water and a large mirror and wet sanded the top plates flat. This is important because so many controls in these carbs are controlled by vacuum, a warped section will cause a leak. There are 3 different top plate gaskets and 3 or 4 different jet block section gaskets and 2 different bottom plate gaskets available. (they all come in the rebuild kit together) Each one blocks off different vacuum ports and what not, each one is used on a different manufacture. Opel, Citroen, Mercedes, BMW etc... lots of European cars used them all with different set ups. It was trial and error to get the correct grouping fitted. The ones that were in the carbs when i got them were wrong, dont rely on what someone did before you lol. That may have been why these were sitting on a shelf.

Second picture is the fuel return needle, the diaphragm was about as pliable as a potato chip.

Third picture is the infamous Zenith accelerator pump piston with its leather cup.
The later replacement pumps are made of plastic and have a rubber cup on them. I have tried both and I'm on the fence about which one works the best.

Fourth picture is replacement leather cups that i got from a Porsche guy. They worked great, but best case scenario is you find a good original pump with its original leather cup still intact. They were a pain to replace, and i ruined one of the pistons.

The last picture is them reassembled and bench adjustments finished. There is a website that has the Zenith 35/40 manual on it. I used it for rebuild tips, bench and running adjustments.

Zenith Carb Manual TOC

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

Here they are on the car, mostly installed. Also the airflow meter I needed to adjust them correctly.

Overall it was a good investment, the vacuum throttle control is very nice when the A/C is on or if you are trying to park in a parking lot and putting strain on the engine from the power steering pump. Gas mileage is up too, I get about 15 around town and 19 mpg on the highway on premium.

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

The Webers should be salable.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Yea i thought about that. I cleaned them and they are sitting on top of my desk next to my original fan clutch. I have a hard time throwing anything away from this car lol.

__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson

During my last deployment I scoured the internet for about 4 months and found someone selling wood trim out of a W111. Their car was wrecked. The lower dash trim had been broken on the passenger side, I glued it back together and filled in the splits with filler. The repair isn't the prettiest thing but my car is not a Concours car, nor will it ever be. With shipping i paid 150$ for all the windshield trim and the trim that goes around the windows. Still looking for the upper and lower door panel trim.

I had to drill small holes for the window trim, the seller included all the original screws.

I thought about re-staining the windshield trim but i ended up not doing that. I know its very badly faded but i like it. I smoothed everything with steel wool and put 3 layers of boat varnish on it.

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__________________
"It's what non-car people don't get. They see all cars as just ton-and-a-half, two tons of wires, glass, metal and rubber. That's all they see. People like you or I know, we have an unshakable belief that cars are living entities..... You can develop a relationship with a car, and that’s just what non-car people don't get."
-Jeremy Clarkson