I have a 300D Turbo 1985. I broke the plastic fitting on the top of the radiator that connects to the line going to the plastic overflow tank (Don't know how I did that was only checking around the air cleaner). Since it broke off flush with the radiator there was nothing to connect the line to. I managed to snap a plastic vacuum fitting into the radiator were it broke off and it seems to have a nice secure fit and drove some 80 miles with the temperature at 110 max which is quite normal for my car. Any opinions on whether I need a new radiator? I'm thinking I can use a tap to make a threaded hole and find some threaded plastic or metal fitting?

if you arent missing any pieces i dont see why you couldnt try to epoxy it. be sure to clean well using something like paint prep,
then drive around town for a while to be sure it holds (as opposed to taking off on a crosscountry trip)

tom w

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[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.

Hi Raslaje,
I too accidentally broke that 90 degree plastic fitting off my 300CE some time ago - I think they may become brittle with age. I went down to the the local MB dealer & paid the equivalent of about US$5.00 for the new part. I was surprised they actually had the part in stock, and the tech behind the counter said they break all the time, & the same part fits a no. of models, so they always carry plenty of them.
I just thought for the sake of a couple of bucks, and to save you stuffing around making some aftermarket add-on looking part, you can easily replace it & know it works how it should.
Cheers.

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Marc Whitting
Australia

I seem to recall an old thread where someone repaired that problem using a gutted tire valve.

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Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

Marc
I just checked to see if the fitting can be replaced. It doesn't appear so on my radiator. The top of my radiator is black plastic with the Mercedes logo and the wording 'Behr'. The plastic fitting is an integral part of that black plastic. I'm going to search the internet for any info on the other two suggestions (tire valve or epoxy type).

Well I'm still using the vacuum fitting (not that I want to) but to let others know that its a good temporary fix. I got sidetracked with other car problems. Some of my searches indicate that the black radiator plastic tends to fracture easily and is particular as to what type of epoxy you use. I don't want to try a hasty cure and kill the patient.

Get a new radiator -- the upper hose connection is just as brittle as the reservior line, and unless I'm mistaken, the reservior is pressurized. You are running unpressurized. Would account for running too hot, anyway.

You do NOT want to blow the upper radiator hose off the rad on the highway, believe me.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

A big ditto to what PS Fred just said.

Forget about epoxy. It ain't gonna work, not for long anyway. Forget all of the other rig-job-back-woods-hill-billy solutions that have been posted here about radiators.

You might use these out on the road in an attempt to make it home, otherwise, do it right - get a new radiator. It's likely due for changing anyway.

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Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

I'm not sure about the 123 model, but on the 124 this fitting is replaceable. In March a 1994 E420 project car started leaking from this fitting because part of it broke off. Fastlane has them for $2.52 and I was thrilled that is was such an inexpensive fix. On the 4th of July weekend the radiator developed a large split on the side so I ended up replacing the radiator anyway. It does appear that if this small fitting cracks, it indicates the radiator could go any time.

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I repaired the fitting with epoxy, but because I did not replace the complete radiator I almost lost a complete engine. The plastic top and bottom section become brittle and my top hose connector broke where the hose clamp is tightened. REPLACE THE RADIATOR. Hope everything works well.

I keep a spare on the shelf for our 124's ...known problem. For the same reason i keep an ovp, A/c relay, and a fuel relay on the shelf as well.

Very cheap insurance, if you have to rely on your car daily.

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1989 300ce 129k
( facelifted front,updated tail lights, lowered suspension,bilstein sports, lorinser front spoiler, MOMO steering wheel, remus exhaust,stainless steel brake lines). (Gone)

1997 s320 154k (what a ride). Sold with 179k miles. Replaced with Hyundai Equus

1994 e320 Cabriolet 108k



1972 280se 4.5 153k Owned for 12 yrs, sorry I sold it


[/SIGPIC]

All I can tell you is my Toyota had plastic radiator "tanks" (I think that is what they call those big pieces on each end of the core). Anyway one day some little cracks appeared, and since I consider myself somewhat of a glue aficionado, I applied some special epoxy that I had. I roughed up the surface real good and I would have bet anyone that I had a permanent repair. Nope, the stuff started leaking within a week. So I have to agree with the previous posters who said "it won't work, get a new one!!". On the other hand I am a little intrigued with the tap idea, but I would worry about the brittleness of the material. Might be a good experiment, unless it fails in the middle of the desert... or in the middle of dessert, either would be bad.

Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

I just wanted to report that the tap idea worked great. First of all let me point out that the radiator appeared to be in good shape with no cracks and the fitting only broke off due to mechanical stress. (I had the air cleaner assembly out and I laid across the hose which is connected to the radiator fitting which normally gets support from the air cleaner intake assembly.)
I bought new (sharp) tap and drill bit, lubricated both with some butter and used them last summer when the summer temperature made the plastic radiator better to work with. I then screwed in a teflon fitting which I wrapped with 1-1/2 turns of plumbers teflon tape. I replaced the thermostat and most of the hoses. The temperature pretty much stayed at 90 degress all winter.