Replacing top piece of Behr radiator - PeachParts Mercedes-Benz Forum

300SD90 · #1 04-07-2014, 12:17 PM

Yet another post about a broken radiator neck...

The previous owner of my Mercedes 300SD 185k miles (who happens to be my uncle) used ties to keep the coolant hose from slipping off of the top radiator neck. Obviously this can only last so long.

My car maintains a good temperature so I do not feel the need to replace the entire radiator, but it's obviously a must if I cannot fix the neck. I have found the top piece of the radiator for sale (see picture) and was wondering if anyone has tried this fix. Is it possible to replace this piece without damaging the radiator?

Thanks!

ROLLGUY · #2 04-07-2014, 12:39 PM

It takes a special fixture and tools to bend the keepers on the aluminum part of the radiator. Years ago my local radiator shop had the fixture and tools, but does not anymore. Replacement radiators have gotten so cheap that very few shops actually repair them anymore. If you find a shop that actually does have the tools, they would be able to replace the tank for you. It is not possible without the fixture and tools. If a new rubber gasket is not provided with the tank, don't even bother buying it. Replacing a tank with the old rubber gasket will insure a leak. It is not worth the labor involved to do so.

300SD90 · #3 04-07-2014, 12:55 PM

Thanks for clearing that up for me! Looks like I'm in the market for a new radiator now. Has anyone had problems with the Nissen radiator? From what I've read Behr is the way to go, but is much more expensive.

ROLLGUY · #4 04-07-2014, 01:03 PM

If you have the piece of the neck that broke, I have heard of gluing (epoxy) a piece of brass or copper tubing inside the neck. Of course the correct size needs to be found. I have one that has a broken neck as well, but have not found the time to source the proper size of tubing. You may want to replace your radiator anyway, and experiment with fixing the old one and post the results here...Rich

Mesalm · #5 04-07-2014, 03:00 PM

I have the same problem and have bought the top radiator end. I am going to try do do it myself. It can be done. The radiator shop quoted me $80 to replace the top with his clamping machine. I am going to try wood pipe screw clamps to squeeze it while I bend the tabs back.

BillGrissom · #6 04-07-2014, 03:26 PM

One thing that might help an iffy repair is using Evans Waterless Coolant, since it builds no pressure. But research first. Best if you have time to get all the water out of the system.

DieselPaul · #7 04-07-2014, 03:28 PM

Quote:

Originally Posted by 300SD90

Thanks for clearing that up for me! Looks like I'm in the market for a new radiator now. Has anyone had problems with the Nissen radiator? From what I've read Behr is the way to go, but is much more expensive.

I've used several Nissens radiators and I've never had one fail.

uberwasser · #8 04-07-2014, 03:38 PM

The Nissens are good.

oldiesel · #9 04-07-2014, 06:42 PM

A while back i bought a new Behr radiator for my wagon ,it was made in south africa and in my opinion poorly done,it was similar to the original but not nearly as well made and really not an exact fit it was fully a half inch shorter in the vertical dimension.I was not pleased with it at all and would have returned it had i not needed the wagon running.
I have no experience with Nissen but others here seem to think they are OK

GregMN · #10 04-08-2014, 12:23 AM

I have removed the top tank, cleaned the excess bar's leak from the cores, and reassembled. That was 2 years ago.

Easy to do:
Use a large screw driver to bend each indented metal retainer "open" so the tank can be removed.
To reassemble, I put the tank back in place and used a strap or two to hold it in place. I used a cold chisel and hammer to punch each section of the metal retainer back in place.

Diesel911 · #11 04-08-2014, 11:43 AM

Quote:

Originally Posted by Mesalm

I have the same problem and have bought the top radiator end. I am going to try do do it myself. It can be done. The radiator shop quoted me $80 to replace the top with his clamping machine. I am going to try wood pipe screw clamps to squeeze it while I bend the tabs back.

Take pictures while you do the Job so if the Job turns out OK you can pass the info on to others.

Diesel911 · #12 04-08-2014, 11:44 AM

[QUOTE=DieselPaul;3313047]I've used several Nissens radiators and I've never had one fail.[/QUOTE

What is the Cost of a Nissen Radiator compared to an $80 Radiator Top?

JamesDean · #13 04-08-2014, 12:29 PM

Nissens radiators go 200-300 depending on model.

I've not encountered any broken necks on any of my cars yet.

I've always gone with a 10-year life cycle on radiators. Maybe longer if you keep up with the flushes/fluid changes.

JB3 · #14 04-08-2014, 12:58 PM

Just wanted to interject that I had an endless coolant leak from this particular seam on an old behr radiator. Had a lot of trouble nailing it down, as it would only leak with the car under load and pressure on the radiator, and as soon as you were idling, it would disappear.

The seam was opening up and closing just enough to create a continuous intermittent problem, so id take extra care with reassembling this properly as it might not by obvious if its leaking later.

In replacing the radiator, I noticed that behr at least has a couple different attachment methods, one is described by GregMN and is basically a flat piece of perforated aluminum thats indented all around the plastic, my leaking radiator was built like that.

I replaced it with a newer behr that was quite a bit more robust and consisted of curled over aluminum hooks in the same spaces. I would not consider that one easy to take apart with that attachment, but it seems a heck of a lot stronger than the bent in tabs.

ROLLGUY · #15 04-08-2014, 02:27 PM

Quote:

Originally Posted by JB3

Just wanted to interject that I had an endless coolant leak from this particular seam on an old behr radiator. Had a lot of trouble nailing it down, as it would only leak with the car under load and pressure on the radiator, and as soon as you were idling, it would disappear.

The seam was opening up and closing just enough to create a continuous intermittent problem, so id take extra care with reassembling this properly as it might not by obvious if its leaking later.

In replacing the radiator, I noticed that behr at least has a couple different attachment methods, one is described by GregMN and is basically a flat piece of perforated aluminum thats indented all around the plastic, my leaking radiator was built like that.

I replaced it with a newer behr that was quite a bit more robust and consisted of curled over aluminum hooks in the same spaces. I would not consider that one easy to take apart with that attachment, but it seems a heck of a lot stronger than the bent in tabs.

And I will add: Do NOT use the old gasket, or you will be sure to have a leak...Rich