This is not good!!
 

This is not good. I need some advice from the "Mercedes Pro's".

Yesterday I popped the hood and was doing my weekly "look at everything" and I found the hose barb coming out of the radiator was weeping around the seal. This is the line that runs over to the expansion tank. So, I removed the barb to find yet another botched repair job. This thing had obviously been leaking before. So, I cleaned the coolant off, cleaned things up with a wire brush and used some JB Weld for the repair. The repair took perfectly and it does not leak any more. It is a solid repair that is difficult to see unless you are looking for it.

Anyway, I get home from work this morning, pop the hood to be sure everything is still tight and dry and I found this:
http://i247.photobucket.com/albums/g...torcracked.jpg

This is not good. It looks like the top tank is cracked in a few places. One along a seam and another at the end of the tank. It has not lost any coolant yet. So, this must have just happened after I did the repair yesterday. Now it is pressurizing properly because the leak around the hose barb is fixed. But is it over pressurizing?

Would an improper or bad cap cause the radiator to crack like this? I was given one the other day and I fear it may have been the wrong one.

Is this something I can trust to a Local radiator shop? Or should I get a new one. I'm not thrilled about forking out $400 right now for a new radiator.

Any input on this is really appreciated.

Welcome to the club!

http://i3.photobucket.com/albums/y71...r/P6130014.jpg

I was tempted to do a repair with fiberglass mat and JB weld but I take this car long distances over the road and I'd really rather not have to fork out the big bucks for an unexpected repair at a dealership far from home when I can take care of it now in a controlled environment.

BTW, shop around a little, radiators can be had for much less than $400. Mine will be less than $250.

Since you don't want to replace - go back to step 1 with the JB Weld. Make sure you rough up the area around the leak with some 80 grit to give good adhesion. Keep an eye on it while JB is good I have not seen it to be permanent on radiators.

Yep... That is a bad day my friend.:( At least we were able to catch it before it left us sitting on the side of the interstate with the hood up and cars wizzing by at over 80 MPH. That is not my idea of fun.

I'm willing to go cheap on the radiator. But not so cheap that it is going to leave me stranded. This car sees 400 to 600 miles a week.

I have found a few in the $200's. Looks like one is made by Nissens? If I remember correctly they made a pretty good replacement for my old Volvo 850's and V70's.

Anyone else have any thoughts on this?

A bad cap can cause overpressurization, and that can crack the radiator (or worse yet... the heater core). An auto repair shop with a Stant pressure tester can test your cap for you.

My 300E has a Nissens replacement, and its been great so far...

I bought a new aftermarket rad that was all metal, copper core with brass tanks for my 240 for $175. It fit well but does not have a bottom drain.
I am happy so far.

I got a good used Nissens radiator. PM me if interested.

I bought a new aftermarket rad that was all metal, copper core with brass tanks for my 240 for $175. It fit well but does not have a bottom drain.
I am happy so far.

I'm not doing JB Weld on those cracks. Not worth risking the engine over that. I found one at the local radiator shop for $210 plus tax. Brand new in the box. Most of the ones I'm seeing online are $240 to $260. Where did you find one for $175?

I'm definitely going to have the cap tested. Thanks for the info. on that. Does Autozone or Advance have a tester like that?

I'm still looking.


Edit: I found one for $177 here:

http://www.***********************/search/?N=11142+1668+4294963043+9235

They might have a tester. Some of the chains have tool loaner programs, I don't know if a pressure tester would be part of that, it's worth checking. If you have a friendly local auto repair shop, they can test your cap for you in like 30 seconds. It'll take longer for them to dig the tool out of it's storage place than to actually test the cap.

i have a stock rad from a 82 300SD, good shape, was gonna use it in my project but i needed a different shape. $100 plus shipping if anyone is still looking for one? email me as im not on here much. dealwithit_000@hotmail.com

cheers
ken

Ok... I got a new one. It will be here in a day or 2.

Thanks for all the help with this. I was freaking out there for a little bit.

Does anyone know a source or size for the little radiator hose beneath the thermostat housing? That is the only hose that has not been replaced. I figure now is the time to do it.

What rad cap do you have? Does it say 120 on it? If so its the correct cap.

Here it is. It says 100? Is that good or bad?

http://i247.photobucket.com/albums/g...peed58/cap.jpg