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:


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.

__________________
AJ

1985 300D (SOLD)