Two odd findings while replacing filters
 

My car is a 82 300D

First odd finding:

1. When I replaced the air filter, I noticed that the filter was filled with oil. There was a lot of oil in the air filter compartment. What does this mean? This can't be normal, can it?

2. When I was priming the fuel filters with the hand pump, it got to the point that each pumping squirted fuel through the sides of the pump. Does this mean that it is time to replace it?


Thanks in advance.

RE: Two odd findings while replacing filters
 

Yes it is called an oil based air filter though i didnt know an 82 benz had it but yes it is normal.

Question 2-no idea

RE: Two odd findings while replacing filters
 

The '82 has a paper filter. What you are seeing is blow-by. Diesel engines have much higher compression than gas engines so they get a bit more blow-by. The blow-by while not a good thing is normal on most of the 123 series cars that have a lot of miles on them. The 300D turbo seems to be even worse and soiling the air filter with oil once the cars get a little wear in them. My 240D has over 360K miles on it and the blow by is very noticable if I pull the oil filler cap with the engine running. The air filter is cheap so I just replace it more often than I did when it only had 100K on it :D

The primer pump is known to squirt fuel every where when priming the filters. The old style pump has a large cream colored knob that you unscrew and then pump to prime the filters.... They leak really bad when they get old. There is a new style primer pump that has a little black knob on top that is spring loaded so you dodn't have to unscrew it to pump it. All you do is push it with your thumb a few times. The new style pump is MUCH better than the old style (in my opinion). The new pump is cheap (about 20 bucks) so it's worth changing it out. There are several places that sell the part but I bought mine over on buymbparts.com (I have nothing to do with them I'm just a VERY happy customer).

The pump can be a bit hard to change on the 617 engine. there is not much room in there for a wrench. I removed my old pump by using channel-locks on the pump body and unscrewing it that way. When you put the new pump in you can't use the pliers because they will damage the new pump. A short wrench works really well. The new pump will come with a new copper seal that goes between the primer and the injection pump, make sure you use it. Over all a 4 on the "extra beer and cuss scale" but only because it's hard to get a wrench on. It took me about 20 minutes to change it.

Good luck,
Tony T