Extra primary fuel filter? - PeachParts Mercedes-Benz Forum

SeaPhile550 · #1 02-12-2014, 12:34 AM

Seems I have a extra primary fuel filter. The filter is before the pre filter. Not sure if this is a normal mod as I could find anything like it in several pics from a google search. Located on the firewall, passenger side.

tangofox007 · #2 02-12-2014, 12:41 AM

Quote:

Originally Posted by SeaPhile550

Not sure if this is a normal mod as I could find anything like it in several pics from a google search.

Is there a such thing as a "normal mod?"

I have a Stanadyne FM-100 filter between the stock primary filter and the fuel pump on an '82 300D. No downside noted. I do drain a little water out of it sometimes.

SeaPhile550 · #3 02-12-2014, 12:50 AM

Adding a new stereo is a "normal mod", why wouldn't a extra fuel filter?

tangofox007 · #4 02-12-2014, 01:06 AM

Quote:

Originally Posted by SeaPhile550

Adding a new stereo is a "normal mod", why wouldn't a extra fuel filter?

One thing for sure: I can install a fuel filter or a stereo in far less time than I can conduct a study to determine if either is "normal" or "abnormal." (The determination of which produces no apparent benefit.) I suppose it all depends on whether one is concerned with efficiacy or about winning a popularity contest.

Zacharias · #5 02-12-2014, 01:59 AM

Some people aren't content with the stock setup, either on the basis of the filtering capabilities of the stock spin-on filter, or the lack of a drainable water separator. Similarly, some people run additional oil filtration under the hood.

If it is important to you, then it's a fine idea as it will contribute to your piece of mind.

If it isn't, then someone will buy it from you on eBay.

toomany MBZ · #6 02-12-2014, 06:39 AM

^ Yeah, that's a water separator.

I have one from M Source, but the damn filter fell off a couple of times, my fault, I imagine. Don't use it any more, but its there if I decide to try it again.

They are for diesels that get limited use.

SeaPhile550 · #7 02-12-2014, 09:16 AM

Been trying to find a replacement for the car quest filter. Couldn't find a good replacement. What's the importance of keeping it around? I get it's job, but it's not a engine saving piece and I can do just fine without it eh? Not sure how common it is to have water in the system or is a region type deal like block heaters. I know it "rains so much" in Seattle but I would imagine if that was the case then I have other issues letting water in the system.

cooljjay · #8 02-12-2014, 01:38 PM

Judging by the tar under it and on the air cleaner....it was used for wvo application....get rid of it and set the car back up to normal fuel...

SeaPhile550 · #9 02-12-2014, 03:18 PM

Thanks. I'm gonna by pass it to see if it fixes my fuel issues. I'm not getting any fuel to the pre-filter. Since this is before the filter I'll hope its that filter. If not then it's on to the strainer in the tank. Or my primer pump isn't working. I have only had this car for almost two weeks and I will be ordering new lines and filter and doing a purge and just cleaning the crap out of everything. Any recommendations for purging?

ah-kay · #10 02-12-2014, 03:33 PM

It is NOT an extra filter. It is a diesel water separator which is installed correctly, before the primary filter. I have one in all of my cars. They do a great job. I would leave it in place but change the 'diesel water' filter. There may be bad fuel before with a lot of water trapped inside.

You can by-pass it first to see whether it resolves your problem but I would recommend leaving it in.

SeaPhile550 · #11 02-12-2014, 04:43 PM

Thanks Ah-Kay. I do plan on leaving it in. Not like the car is under warranty. Gotta do all I can to make sure the ol' gal is happy. Last question in regards to the filter. Is quality of this filter matter much as it's before two other filters? Or should I look to ditch the Carquest filter for. Better brand?

ah-kay · #12 02-12-2014, 04:50 PM

Quote:

Originally Posted by SeaPhile550

Thanks Ah-Kay. I do plan on leaving it in. Not like the car is under warranty. Gotta do all I can to make sure the ol' gal is happy. Last question in regards to the filter. Is quality of this filter matter much as it's before two other filters? Or should I look to ditch the Carquest filter for. Better brand?

Personally I like visible washable stainless steel filter with a drain. That is what I have. I am not familiar with your brand. You cannot tell the condition inside.

SeaPhile550 · #13 02-12-2014, 06:32 PM

Yeah that sounds great. Got any links to the manufacturer? I'm guessing this was a kit or something eh? Or is this a factory option?

Skid Row Joe · #14 02-12-2014, 06:41 PM

I had a nice in-line water separator on my main fuel filter on my I6 Isuzu diesel engine, located at the fuel tank. The filter and attached water separation chamber assembly brand was Racor. The size of the Racor kit assembly was similar in size to the FL-1995 7.3 liter Ford PSD's oil filter. The chamber or container was hard, clear see through plastic so when the water that got separated was on the bottom of this long filter, and had a spring -kept button to push to let the water out when you saw any collect there. Really worked neat too. The OEM main fuel filter located near the engine was woefully dinky - about 1/2 the size of the W126's main fuel filter, to give an idea of how small.

ah-kay · #15 02-12-2014, 06:54 PM

Quote:

Originally Posted by SeaPhile550

Yeah that sounds great. Got any links to the manufacturer? I'm guessing this was a kit or something eh? Or is this a factory option?

I don't have any recommendation as the one I use is no longer manufactured. The brand is 'Alert' and it pops up in eBay now and then, basically new old stock.