1985 Mercedes Benz 380SL - fuel filter change
New-to-me 380SL, so I am doing routine maintenance. Here is a little bit on changing the fuel filter (which should be a piece of cake). Oh, grasshopper, what you are about to learn.
Went to Advance Auto and bought the cheapest fuel filter for my 380SL -- $35.00. That is nuts! No fuel filter should cost more than $8.00, but I swallow hard and shell out for it. My first warning sign.
- Fuel filter location
It's in the back of the car, passenger side, behind the rear wheel. See pic 1. It is part of an assembly consisting of:
- fuel pump
- fuel filter
- fuel accumulator
- Fuel connecting line and crush washers
Connecting the fuel pump - filter - accumulator is a single line, with two banjo fittings and a a regular fitting. How absurdly complicated! Mine was leaking, at least it started leaking after I tried to remove it. I'm a fairly good wrench, but this thing was old and it cracked. So, I tried to find a replacement. $125 on eBay. Believe it or not, my local Mercedes dealer sold it to me, brand new, for $45. I never expected a dealer to beat out eBay. It's all connected using crush washers. Again, the dealer had the best price, $1.00 each. See pic 2 and 3. And by the way, might as well change the fuel filter while I'm in there ... my original, simple project.
- Pump Cap leaks
Can you believe this? Everything is looking good, but there is a drop of gas leaking. Ends up it is the bolt / cap at the end of the fuel pump connection. The cap itself. Crap. Dealer = $8, and glad to get it.
See pic 4.
- Now the pump leaks
Assembly is pretty straight-forward, but now my pump is leaking. The pump itself. I had held the pump firmly with a pair of channel-locks while tightening the cap, and I think I squeezed it out of true. Anyway, now the dang pump is leaking too.
- 77 fuel pump
It just so happened that I have a fuel pump from a 77 450SL, and it's in good shape. It also looks more solid than my 85 pump. But it's not an exact match. But I decide to use it anyway. So, here's what I did:
- Cut connector
Removed the new $45 connector line. Cut my old connector line above its leak, but below the fuel filter banjo connector.
- Connect line to filter and accumulator
Normal connection to accumulator and fuel filter. However, now I have a cut line at the bottom, and it needs to connect to the 77 fuel pump. So, I buy 2' of high pressure (injector) fuel line from NAPA, and use about 6" of it to connect the 77 fuel pump to the cut connector line. See pic 5.
- Ta da
So far, so good, and it's been about 4 months. Maybe one day, I'll get back in there and replace the pump with the proper model..
What a royal pain in the butt! All this trouble just to change a fuel filter. Now I love cruising in my 380SL, but from now on, I don't want to hear about superiour German engineering. This is just plain dumb. Total time: 6 hrs, total cost: $100 (and I did it on the cheap).