Radiator Fix
 

Hello all, I wondered if anyone has a fix for the radiator neck leak? I have a 1997 E420 and it stared leaking a few weeks ago. I have read about the inserts and JBWeld. Does that work or has MB produced a similar repair kit?
Thanks for the help.

I would not to jb weld on a cooling system. if it fails. you will blow your head gasket if your not paying attention to your engine temps.

when I first bought my 190e. a week into owning it, the neck broke on the radiator. I removed the rad and took it to a rad shop and I think it cost 100bux to put a new plastic end tank on it. I remember the shop owner saying he wasnt making any money off this job.. another younger guy wrote me up and charged me less?

Buy a new radiator - don't risk your engine.

Then address the basic problem of why this failure occurred.
Make sure you are running the correct M.B. coolant in correct proportion.

The sleeve
 

works as a preventive measure. Put one in your new radiator (or new tank).

It will NOT work as a reliable repair.

JB Weld is not waterproof. It will fail.

How big is the leak? A pinhole can be patched. Larger cracks = new radiator.

Here is my experience.....
Original Behr radiator lasted 11 yrs & was replaced with another Behr (new versions have the neck reinforced with metal sleeve). But didn't seem to help much, bc this one lasted 12 yrs. I tried to repair the crack with JB-Welds, the repair looked good & promising...but didn't last & start dripping coolant again. I am glad it didn't blow out on me & leave me stranded or damage my engine. So for my 3rd radiator, I decided to give Nissen radiator a try instead of a Behr (bc even with the metal sleeve reinforcement, didn't seem to make a difference), hoping Nissen uses better plastic material for the neck. :D

Interesting.
Our old 300E was still running on the factory Behr radiator after 18 years. The only issue was the overflow connector in the top failed and dripped coolant for years before we fitted a new connector.
Is there some misalignment that is causing the radiator hose to place lateral loading on the connection to the radiator?

Also -- if you are due for an emissions test, you will not pass/be tested if the radiator leaks.

I learned this today, when I went for my annual inspection. In fact, I double-failed because I also need a new serpentine belt for the safety inspection. My goal is to buy the parts and do both replacements early tomorrow morning, and get to work by noon.

Belt is easy. Radiator is just hoses, pipes and clips. I hope I am right... :)

FYI -- That bit I said about being failed for emissions is not necessary true in all cases. Upon further inquiry today, I was told that the inspection shops can’t have coolant leaking onto their dynos. Makes no sense to me, but whatever.

Despite my endless battle with patched radiator leaks on my previous car (documented among these threads) I can’t believe I am nonetheless tempted to try and patch the pinhole I currently have. This radiator is original equipment and the pinhole is very tiny.

However, I know if I patch it a new one will erupt elsewhere – or the patched one may simply get bigger. And, after about the third repair attempt, I know I will have spent more than what a new radiator costs (in time, materials, and needless frustration).

No thanks; not going down that road again. I bought a shiny new Behr-Hella this morning and will take care of it the truly inexpensive way. :D

Radiator Fix
 

Thanks everyone for the replies. Looks like a new radiator will fix the problem.
Is it a DIY job. Doesn't seem to difficult. I live in Kent, WA. Does anyone know of a good shop?

Absolutely a DIY. I did it this morning before coming to work. Doesn’t make sense to pay someone hundreds of extra dollars to do something so straightforward.

This is the DIY for the W124. Yours should not be too different.
http://www.peachparts.com/Wikka/W124Radiator

Enhancements/clarifications to the article based on my experience with the 95 E320:

• For the transmission cooler line bolts use a 19mm wrench. (They are not oil cooler lines as the article states.) You will lose only about 2 tablespoons of trans fluid in the process.
  
  The transmission line bracket at the bottom is secured by a single bolt. The bolt head is flush with the plastic “foot” of the rad so you have to go at the 10mm nut from below. For easiest access, remove just the two front 10mm bolts on the belly pan and drop it. Then you can easily loosen the bracket bolt, as well as the 6mm bolt on the clamp of the lower hose that runs to the expansion tank.

The only things that slowed me down were the fan – specifically, getting it back on since my hands are too big to maneuver easily between it and the radiator to refasten the bolts; and getting the radiator clips back on (i discovered strong, needle nose-type pliers make it much easier.) Eliminate these two obstacles and this is a one-hour job, at most. (But don’t try to convince your local shop of that.)

Finally, the price spread between OEM Behr and aftermarket radiators is too small to waste time bargain hunting. Get the real thing.

If the plastic neck is where the failure happened, have your engine mounts inspected. I have often seen the telegraphed vibration cause the neck failure on the plastic radiators. I also agree that JB Weld won't handle the heat or pressure on the plastic.

Pulled some pics from the camera.

1. Out of the box.
2. On the car.

Note the collapsed upper radiator hoses after sitting overnight. My expansion tank cap was faulty and was probably defective for a long time but required the complete reseal of the cooling system –new heater hose, new water pump, new radiator hoses, and new radiator -- to become evident.

New cap is going on today.