OVP Relays -- Which Ones Are Faulty? Part #'s...
 

Hi. Can anyone tell me which particular OVP relays -- the part number and country of manufacture -- are known to be faulty? I have a '91 300E and I was told by one general tech (not MB tech) that the OVP I have appears fine. But I know that posters on this board frequently cite bad OVRs and also the announcement from MB in 2001 about faulty OVRs, and I want to make sure my OVP relay is okay/will continue to be okay. What I need is the faulty part numbers and countries of origin. Thanks in advance.

As a related aside, a few years ago, this board helped me replace a bad fuse on the OVP relay. A variety of problems absolutely stopped when the fuse was replaced. Then, last spring, the car began acting up again as far as some hard starting after it is driven only for a mile or two in warm weather (it only happens from April - September; and it only happens when I try to start it after having shut it off the first time, i.e., the rest of the day it is fine! Is that odd?). Here it is spring again, and the car is doing the same thing!

Search feature has pages on it..

Original is 000 520 52 45 - Austria

Repalced by 000 520 67 45 ...

Oh. Thanks Arthur. Only 1 part number? Only 1 OVP relay was faulty? The OVP relay I have is German made with a different #, so I assume it is okay. I did search -- a few different ways (OVP relay, "OVP relay AND overvoltage protection relay") and the closest result I found was my original 1991 post where Gilly said that he would give me the part number if I wanted. In no other search result page was there a mention of the actual part number. In fact, I think I was able to find more result pages in past searches for OVP; I guess I just had bad luck this morning. Then just now, to doublecheck, I searched for "OVP" only and I found tons of pages!

That is the OVP change that I am aware of..
On the Search feature, the less description you use , the more post you will bring up..
Like 'Gas" will bring up 10 times the post that "Gas Tank " will...

And Title only vs. Entire thread ...
Sometime you want to be specific, but when searching for a past post that you remember seeing, the less gives you a better shot.

What works well for me is to think of what words would be in the content of a thread with an OVP problem/remedy..
So, by searching "OVP Faulty Part", you instantly come up with a good Post including the part #...

http://www.peachparts.com/shopforum/tech-help/54371-troubleshooting-94-e320.html?highlight=faulty+ovp+part

The OVP has a relay inside with mechanical contacts. It is a wear item, and can be expected to fail eventually. Some runs of the product may have initial problems, or fail prematurely, but don't judge the need for replacement based on the criteria you mention. Either a 'good' one or 'bad' one will likely go south - eventually.

Steve

It is not wear on the moving parts that causes failure it is cracked solder joints. They can be repaired by opening up the can and carefully resoldering the joitnts.