Hi-
I accidentally pulled the overflow nipple out of the neck of my w115 220d radiator, and would appreciate some advice on how to fix it (see pic). Because the pressures at this location are minimal (external to the pressurized cooling system), I assume strength is not a major concern (other than pulling this dumb move again). It appears to have some silver-colored solder material on it originally.

I see some options to include:

1) just punch it back in (it is a reasonably tight fit) and not worry about leaks
2) punch it in with some silicone
3) punch it in, and then seal with epoxy (jb weld or similar)
4) use a low temperature solder like all those videos on youtube for alumaweld, hts 2000, alumaloy, durafix, etc.

Any thoughts? Solution 4 seems the closest to the original design, but I also cannot afford to melt a hole in my radiator (~$1K new right now). I don't like to half-arse things, but I also don't want to make the problem any worse.

Also, does anyone know what material the neck of the radiator is likely to be? That info would be helpful in figuring out the actual risk of melting a hole in it with my cheapo bernzomatic propane torch.

Thanks.

Attached Thumbnails

 

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

Looks like brass from the image. I'd be inclined to go the JB Weld route. There's no pressure at that point so you just need a good seal and something to support the fitting.

Whatever you do keep an eye on your fluid levels in the radiator - not the overflow tank. If it loses a seal, the vacuum in the radiator as it cools will bleed air into the radiator rather than drawing coolant back in.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

I'd JB Weld it. I don't think the W115 has an overflow-tank.

Happy Motoring, Mark

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DrDKW

I would remove the Radiator, and take it to a Radiator Shop and have them Solder it back in.

It was originally Soldered when it was new.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

basic pipe sweating unless it is brass then it'll need to brazed in, either way pretty simple both processes are basically the same just take your time. or as said above a good radiator shop will be able to repair it. personally I wouldn't JB it as any excess can make it's way into the galleys, scoring hoses, or cause damage to the water pump. again just my thought on that.

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All gave some, Some gave it all ~ 9-11-2001 Never Forget

People shouldn't fear their Government, The Government should fear its people.

I would braze it back on. It is not a high pressure fitting but if you want it done properly...

You should be able to drive the car to a radiator shop if you don't want to do it yourself.

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1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge

This makes too much sense, Charlie.....

Thanks everyone for the helpful advice. I bought a few rods of HTS2000 (a low temperature "welding" (brazing) rod) via ebay prior to putting up this thread, because I was in a panic when I saw the price of a new radiator. I hadn't yet realized that my failure was not at a pressurized location. I am going to ponder everyone's advice a bit more before I come up with a plan. But right now I am thinking of trying to sweat the joint like copper pipe using Oatey pipe solder (melts at 460F).

I did have one followup question, which hopefully someone can address here. And if not, I may ask over in the Vintage forum. Mark is correct above that the w115 did not have an overflow tank originally. There is an overflow tube which just routes the coolant down to the bottom of the engine compartment. Does anyone know how often one would have had to top off the coolant with this sort of system? Mine has been retrofitted with a tacky overflow tank so I don't know how the system worked as originally designed. For whatever reason, I thought the overflow tank on a modern car was used every time the car heated up. But clearly that couldn't be the case with a w115 because there was no way to get the overflow back. Is an overflow tank only needed during extreme high temperature events? Thanks again.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

You know me too well, SRJ.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).

i would solder it back on, but you need to pull the radiator and submerge it in water up to the neck otherwise you will run the risk of un-soldering the whole neck.

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"NEW" 1984 300D TD needs some love

the recovery tank insures that the system operates with NO air in the cooling system.

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"NEW" 1984 300D TD needs some love

This is the perfect time to pull the radiator, have it boiled and tested at a radiator shop and have them fix the nipple....I was only charged 40$ when I took an old dodge dart radiator to a radiator shop....it came back, like a brand new radiator...

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