PeachParts Mercedes-Benz Forum

PeachParts Mercedes-Benz Forum (http://www.peachparts.com/shopforum/index.php)
-   Diesel Discussion (http://www.peachparts.com/shopforum/forumdisplay.php?f=15)
-   -   Tank Screen (http://www.peachparts.com/shopforum/showthread.php?t=156266)

hawthorne90250 06-18-2006 08:16 PM

Tank Screen
 
Hi
I started using biodiesel (B99) about a month ago and am pleased with it, but i have noticed a slow steady decline in power, the prefilter and filter are new and i am wondering if there is a filter/screen in my tank that maybe slightly blocked (I did not clean the tank before switching) If there is a filter/screen how do i get to it? do i have to remove the tank?:D 1979 300D
Thanks

engatwork 06-18-2006 08:24 PM

You don't have to remove the tank. Look underneath the car close to the differential where the hose comes out of the bottom of the tank. The fitting that the hose fastens to should be a large nut (don't remember the size off the top of my head). Remove the hose and unscrew the nut and the screen will come out with it. Get as much fuel out of the tank as you can prior to removing it. The rest will come out upon removal;).

TheDon 06-18-2006 08:28 PM

its like a 43mm or somewhere in that area.. a set of channel locks should work or the tool mercedes benz has for the job

hawthorne90250 06-18-2006 08:30 PM

Tank Screen
 
Quote:

Originally Posted by engatwork
You don't have to remove the tank. Look underneath the car close to the differential where the hose comes out of the bottom of the tank. The fitting that the hose fastens to should be a large nut (don't remember the size off the top of my head). Remove the hose and unscrew the nut and the screen will come out with it. Get as much fuel out of the tank as you can prior to removing it. The rest will come out upon removal;).

Is the screen a fine mesh or paper?, can i replace it or just clean it?
Thanks

TheDon 06-18-2006 08:33 PM

its a plastic.. you can remove and clean it..

Keith_otr 06-18-2006 08:51 PM

I know this is probably just a "quick fix" and may not last long, but it did apparently work for me.....

My car was very sluggish, and no matter how much I tightened the hose clamps, my primary filter was full of bubbles....apparently, the fuel pump creates a very strong suction and it was pulling air in from somewhere (My fuel lines are in good condition as they were recently replaced). I suspected my tank screen was clogged since I've been running B100. Here's what I did.....I loosened my filler cap, disconnected the fuel line at the primary filter and used my garden sprayer (the pump up kind) to blow air through the line until I could hear bubbles in the tank. I did this about 20 times, allowing the fuel to flow back into the line each time to help flush out the crud as it was forced backwards by the air pressure. This was about 2 months ago and it seemed to have worked. There is no air in my primary filter anymore, but it does have small specks of crud in it. I'm hoping that the majority of the crud was broken up enough to pass through the tank strainer....the primary filter is much easier to change.

Maybe it's worth a try.....

Keith

1983/300CD 06-18-2006 09:58 PM

Sounds like Keith needs some enzyme treatment.

To clean the tank screen, (this is not the only way, but probably the easiest, least messy way) drive out as much fuel as you dare, then take a vice grip with short segments of pipe over the jaws and clamp it onto the 6" rubber line coming out of the bottom of the tank. Then, take off the hose clamp connecting the rubber line to the hard fuel line. A little fuel will leak out, but not a whole lot. Position the hose over a fuel can, and release the vice grips. Let it drain for 5 minutes. The hose screws into the screen, which screws into the tank. Sorry, I don't know the size of the socket, mine was a bit loose so the screen came out with the hose when I cranked on it with channel locks.

If your rubber fuel hose is too old, you could damage it with too much pressure from the vice grips, so be careful. You need less pressure than you think to stop the flow.

You might also want to check the tank vent. There is a little horn-shaped piece under the car on the driver's side that vents pressure to the tank. Do you ever notice a wooshing when you remove the fuel cap? That can also rob you of power.

Biodiesel300TD 06-18-2006 10:17 PM

Quote:

Originally Posted by hawthorne90250
Is the screen a fine mesh or paper?, can i replace it or just clean it?
Thanks

The screen is metal. You can just clean it and reinstall. I would buy a new o-ring to replace the one that is on the car. Apparently there is a good chance it will leak if you reuse the old one.
I did this on my wagon a few months back. I still had about 2 gallons of fuel that I had to let come out before I could really take the screent out. it was kind of a pain. So if you can use as much as humanly possible before attempting the removal. Or be prepared with something to catch fuel in and a lot of rags for clean up.

I was pretty surprise that mine was perfectly clean after 8000 miles of mostly B100 use over a years time.
All that work for nothing, but I guess I got some experience and some piece of mind out of it.

1983/300CD 06-18-2006 10:24 PM

I got an assortment of O-rings from Lowe's. The largest was still a little small, but it stretched to fit.

But, here's a proper one:

http://www.***************/search/productx.aspx?sid=wffo1xnnw4egfx55ajdbvh45&makeid=800016@MERCEDES&modelid=1193565@300CDT%20123.153&y ear=1983&cid=22@Fuel%20%26%20Air%20System&gid=6262@Fuel%20Pump%20Tank%20Seal

(Or talk to Phil)

Brian Carlton 06-19-2006 12:26 AM

Quote:

Originally Posted by engatwork
The fitting that the hose fastens to should be a large nut (don't remember the size off the top of my head).

46mm or 1 13/16".

The proverbial problem is the very limited clearance for the socket and the wrench. M/B makes a special short 1/2" drive wrench for this purpose.

Not sure if the 3/4" drive for the aforementioned sockets will work.

sixto 06-19-2006 02:10 AM

In the absence of a pump's influence you can probably pinch a fuel line with finger pressure. Vice grips are overkill but commonly found in toolboxes. Wrap a rag around the fuel line before clamping with vice grips so there's less chance of the vice grips damaging the fuel line.

Sixto

1983/300CD 06-19-2006 06:16 AM

Quote:

Originally Posted by Brian Carlton
46mm or 1 13/16".

The proverbial problem is the very limited clearance for the socket and the wrench. M/B makes a special short 1/2" drive wrench for this purpose.

Not sure if the 3/4" drive for the aforementioned sockets will work.

Maybe a long extension or two.

stock 06-19-2006 06:39 AM

Anyone put on an eaiser replaced screen?
 
I just switched to strait WVO, it sound's like I'll be doing this soon. It sounds like a mess and pain in the rump. Has anyone removed the factory screen and put in a new one? Maybe a pre filter like the one in the engine bay? Have shut off valves before and after? I'm not a real big mechanic type, but would this work?

d.delano 06-19-2006 08:19 AM

Quote:

Originally Posted by Brian Carlton
46mm...M/B makes a special short 1/2" drive wrench for this purpose.

Baum Tools item# M0035 Fuel Tank Filter Wrench


This is different than the socket, item# M0035A

Both will work, the former doesn't need a drive as it has a handle cast into it
The latter requires 3/4" drive IIRC

Jadavis 06-19-2006 11:08 AM

Quote:

Originally Posted by sixto
In the absence of a pump's influence you can probably pinch a fuel line with finger pressure. Vice grips are overkill but commonly found in toolboxes. Wrap a rag around the fuel line before clamping with vice grips so there's less chance of the vice grips damaging the fuel line.

Sixto

I just bend it over and ziptie it. You just need to hold the hose folded over to keep from making too big of a mess.

Another option is to reverse the suction and return lines from the tank. It is a temporary fix.

I really need to hook up an external pump and filter to my suction and return and let it run for a few hours with a tank of biodiesel. Maybe this will get most of the crap out of the tank and into my sock/bag filter. They are easier to clean/replace and much cheaper than the secondary filter on the car. Once the tank is clean you should never have that problem again.

Unless you are doing WVO single tank...then some of the higher melting point fats can collect on the screen.

-Jim


All times are GMT -4. The time now is 05:39 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website