240D Cloging up the fuel system? - PeachParts Mercedes-Benz Forum

masevich · #1 10-22-2009, 05:31 AM

Hello Guys,i already posted the ad before that my 240D Previously ran on veggie oil,the guy previous owner ran it for a year for free...well,we switched back to Diesel,it was stalling out as if it was running out of fuel,well i decided to change the strainer,as we did that,the car started and ran fine for like 5 miles and after it started stalling again loosing speed at wide open throtle,well as i came to complete stop where the car died out,i checked the clear filter under the hood and it was completely cloged up,like all the way..so when i was trying to primer it,it just seemed like its pumping the air,i didnt feel the fuel..well i changed the filter i had with me and the car drove off,about another 5 miles down the road same thing started the car began stalling so i look and the filter cloged again with like old veggie oil or that gunk... what do you guys recomend me to do,please help,i know you guys are experts and heard that you helped alot of guys out with their problems.. God Bess Yall

Crazy_Nate · #2 10-22-2009, 11:30 AM

Well, if there's that much gunk in there, it'll probably be worth your time to drain the fuel tank (there should be a couple of posts about how), and then strain it at a bare minimum. The fuel tank also has a 'prefilter' or strainer in it, you'll want to clean that out too, as it's probably pretty messy.

There are also posts about removing the fuel tank and cleaning it - who knows how much stuff is still in there.

Also, if you think there is gunk in the lines in the engine compartment, I might consider running a diesel purge (there is a good step-by-step tutorial on dieselgiant.com ).

When you're done, make sure all of the fuel lines are well sealed and not letting any air in, prime it (until the IP makes a sort of hissing / buzzing sound). If the primer pump is the old style, it might be leaking air, and replacement with the new style primer pump is usually quick and painless. There are plenty of posts (and perhaps even a how-to) on this replacement.

Best of luck!

kingdoc1 · #3 10-22-2009, 12:16 PM

Find a used fuel tank that has never had veg oil in it and swap tanks.

It is an easy job and you won't have any more problems, assuming you get all the lines flushed well.

In my experience, you might want to check the main fuel filter housing, the last one I did was so bad I just replaced it with a used one.

You might look for one of the plastic tanks (my 82 240d had one, not sure what other years used them) they will never rust inside.

masevich · #4 10-22-2009, 07:49 PM

Hey Guys,I took off the little clear filter and running it straight with out it. I just filled up with Biodiesel and want to run a couple tanks through. Actually got 5 gallons for free. They were doing a promotion. Well if this don't help I'll just change out the Gas tank and check all the lines. After it idles for a long time it runss allitle worse but once it gets going runs good. Well get it running perfect guys,thanks for all the help. It's just a lesson not to buy a car that someone previously ran veggie oil in in a one tank system. They guy probably didn't filter it well too so. Just learn from my mistake

Crazy_Nate · #5 10-22-2009, 07:59 PM

If you've removed the primary filter (the small, plastic one with a screen in it, in the engine bay), running it will only clog the secondary filter. The secondary is a finer filter, and will catch the particles that would have gotten stuck in the primary anyways (it's also more expensive). The primaries are easier to change out and cheaper.

The biodiesel will help clean out everything, but everything that it cleans out will end up in your filters anyways. It'll get cleaned out eventually, you'll just have an interesting time

ah-kay · #6 10-22-2009, 08:10 PM

Quote:

Originally Posted by masevich

Hey Guys,I took off the little clear filter and running it straight with out it. I just filled up with Biodiesel and want to run a couple tanks through. Actually got 5 gallons for free. They were doing a promotion. Well if this don't help I'll just change out the Gas tank and check all the lines. After it idles for a long time it runss allitle worse but once it gets going runs good. Well get it running perfect guys,thanks for all the help. It's just a lesson not to buy a car that someone previously ran veggie oil in in a one tank system. They guy probably didn't filter it well too so. Just learn from my mistake

The reason is that the veggie oil 'etched' all the crap from the fuel tank. I use alternative fuel and I have the same problem after a while. I installed another diesel/water separator filter in front of the primary filter and problem solved. The primary filter is now sparkling clean and the filter in the diesel/water separator is washable. It is a win-win. I think the fuel tank will be 'self cleaned' after a few tanks of normal diesel and a few primary filters.

I would not blame it on the PO as it is the nature of the beast to 'etch' all the crap out. The tank was dirty to start with for a 20+ years old car. Removing the primary filter is NOT a solution. Running B100 will 'etch' more crap out.

I have a lot of success with this guy.

http://cgi.ebay.com/ebaymotors/Diesel-Fuel-Filter-Water-Separator-Mercedes-Volkswagen_W0QQcmdZViewItemQQhashZitem41480dbb24QQitemZ280381733668QQptZMotorsQ5fCarQ5fTruckQ5fParts Q5fAccessories

masevich · #7 10-23-2009, 03:44 PM

Well yesterday the car idled at high rpm for like 20 min and after i started driving it it stalled, i primered it let it sit for awhile after some time it started but ran really rough like up and down on the rpm than went back to regular rpm and ran fine,after that i lowered the rpm because before that i adjusted the rpm to be higher when the car was running weak,so now it seems like its running good,so i will run a couple tanks of biodiesel and see how it runs..

masevich · #8 10-23-2009, 05:01 PM

Ah-Kay so you have 2 clear filters? One is by the little primer pump where did you put the other one?!

ah-kay · #9 10-23-2009, 05:18 PM

Quote:

Originally Posted by masevich

Ah-Kay so you have 2 clear filters? One is by the little primer pump where did you put the other one?!

I do NOT have 2 clear primary filters. I have the same primary and secondary spin-on filter like everyone else. I installed a diesel/water separator before the primary filter, and a heater before it. Look at the lower right hand corner of the picture. The aluminum shape box is the heater with 2 glow plugs, then it goes to the d/w separator, then to the primary filter etc. I bought the heater but wired up the electric and relays myself. I have done 30K on alternative fuel on this set up without any problem. Engine is running strong and smooth but it is due for a valve adjustment. I changed out my pri/sec filters at about 8000+ miles interval.

Running B100 will etch up more crap from the tank. You need to do something to prevent it, otherwise you will be changing filters like a disc jockey.

Hope this help.

pselaphid · #10 10-23-2009, 06:26 PM

My tank had about a quarter inch layer of slimy scum coating the entire bottom third of it and was behaving as described. In my opinion, cleaning such contamination with B100 will be a long, frustrating path compared with pulling the tank, cleaning it, and putting it back in. Its also very nice to you know you really do have a clean tank and you won't have to worry about mystery crud coming loose over the next few years. Also, this car was owned by old people who never ran anything but diesel, so WVO was not to blame in that case, though it will crud up a tank much quicker. I suspect they just let it sit for a long time and let bacteria proliferate along with byproducts of hydrocarbon breakdown, which is not the same thing as WVO polymerization.

Do yourself a favor and pull the tank. The interior is reasonably accessable to long brushes and degreaser. Just be sure and dry it good before reinstalling.

ah-kay · #11 10-23-2009, 07:04 PM

I do not know what it takes to pull the tank and clean it. 1 day to R, clean and R again? I would only do it as a last resort if there are no better methods.

I find installing a washable d/w separator is money well spent. It totally eliminated my clogging problem ( used to clog the primary filter every 10 miles or so ) and now I only change both filters every 8000+ miles. BTW, I use alternative fuel which is more prone to clogging. The d/w separator cuts down on my running costs again.

kerry · #12 10-23-2009, 07:31 PM

I wouldn't run it without the primary filter. In your situation I'd probably rig up two parallel primary filters with a couple of valves to switch between them when one gets clogged up and just keep replacing filters (they're cheap) until the gunk is gone.

masevich · #13 10-24-2009, 04:13 AM

Guys,what i decided to do is clean my tank and check all the fuel lines if they have good flow,and at last if i find cheap injectors ill replace those aswell..will let you know how it will run,if you dont set up this veggie system right and dont filter your veggie oil correct your in trouble,ill let you guys know how the cleaning goes,might even take come pictures and post them up
thanks