Author Topic: Fuel Filter replacement  (Read 2974 times)

chazchuzzlewitt

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Fuel Filter replacement
« on: 09 July 2006, 06:04 AM »
I went to replace the fuel filter on my 350 but couldn't quite tell how the old one comes out- it's held in by the metal clip/clamp on top of the pump but I couldn't see how the clamp comes apart to release it- could anyone point me towards where the bolts/screws are?!
1980 W116 M110 280SE
1994 W124 OM606 E300D
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1980 W116 M116 350SE-sold
1992 W124 M103 300E-sold

adamb

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Re: Fuel Filter replacement
« Reply #1 on: 09 July 2006, 08:26 AM »
I went to replace the fuel filter on my 350 but couldn't quite tell how the old one comes out- it's held in by the metal clip/clamp on top of the pump but I couldn't see how the clamp comes apart to release it- could anyone point me towards where the bolts/screws are?!

Last time I did this job I removed the fuel pump/filter/etc assembly entirely. This made replacement straightforward. I recommend you do the same. This will also give you an opportunity to examine and replace perished fuel hoses. Clamp the fuel hose coming down from the tank. BTW, old Mercedes hoses tend to last a fair while but are more likely to show weakness and leak after clamping.

Adam

Denis

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Re: Fuel Filter replacement
« Reply #2 on: 09 July 2006, 10:52 AM »
Hi

I totally agree with adamb !

And also learn the right technique, an age old proper professionnal mechanic technique that these ancient and expensive cars allow : tightening with a hold/counterhold technique.

When you tighten the err...say 17 mm nut on the fuel filter, note that the filter has a 17 mm or similar holding facing nut surface on the casing or on an intermediate connector. 

Garbagemobiles have no such thing -hey it costs money. But the wise and efficient grey-haired German mechanic knows the classic technique.

Put a wrench on the filter part, place another on a fairly tightened nut on the fuel line, place these two wrenches shifted by about a 15 degree angle so that pressing the wrench handles together tightens the connection.

This uses very little energy to positively tightens the filter.

Now don't do this and tighten any old how and it might leak  >:( and I once stupidly blamed MBZ for this, but it was I that was ignorant).

Dont tune pianos if you dont understand harmonics and don't fiddle  a classic MBZ unless you understand teh concepts but it is way easier than pianos  ;D

Puff-puff, two hours to the soccer game, where is the champagne - we will need it one way or another
 :P

Denis^

Paris, France

Denis

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Re: Fuel Filter replacement
« Reply #3 on: 09 July 2006, 11:05 AM »
As for old gray-haired German mechanics

Dare I say that the British aircraft mechanics of WWII knew the same techniques and with top wrenching and wise dispatch, beat the NAZI invasion.

You Brits on this site may want to know that THIS frenchman has a great admiration for what your grandpapa did back then - good engines, good men, incredible courage, a belief in freedom...while America was ...doing whatever it was doing.



BTW

It may seem incredible but occupied France, before having been totally swarmed by the NAZI army, actually WANTED to unite the UK and France into ONE nation making the huge french fleet a property of the king ! crazy times gentlemen ... but telling of values...

OK back to W116s but I wanted to say this one day or another !

Hey, I have three Brits in my company and they are supporting FRANCE tonight !! good blokes, cheer on !!


Denis

Paris, France

Nutz

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Re: Fuel Filter replacement
« Reply #4 on: 09 July 2006, 11:08 AM »
I thought I'd throw this out there for you to consider though it may be more than you really want to do  8)

Run the gas out of your car to critically low levels then proceed to remove the fuel filter and such pinching the upper fuel hose off.Purchase a couple of gallons of gas in one gas can and then get another gas can and drain all the fuel remaining in the tank into it to remove foreign matter.Let the drained gas sit for a while to let everything that came out settle at the bottom.Then after you're done with the filter,poor the fuel back in.  


s class

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Re: Fuel Filter replacement
« Reply #5 on: 10 July 2006, 10:56 PM »
If you disconnect the fat hose from the tank to the pump, the petrol should gush out like a hose pipe.  If not, the strainer inside your tank is blocked. 

At some point you will need to replace all the rubber hoses to and from the tank if this has not already been done.  30 years is a long time for hoses to last. 

THe most critical thing when replacing the fuel filter or doing other work around the pump is to be meticulously clean.  Any trace of dirt you introduce downstream from the filter will ruin your fuel injection system.

Otherwise its an easy if messy job - just don't smoke while you do it. 

Ryan

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL