E300TD diesel purge proceedure solved!

[crmont]

***EDIT*** CHANGED THE MOVIE TO MPEG-1 FORMAT.
Please try your download again

I came up with a pretty easy proceedure for running diesel purge through my 99 E300TD. Here are 5 pictures and a mpeg2 movie clip. If you watch the clip, pay attention to the sound of the motor as the diesel purge begins to work. (you may right click, save target as..)

http://home.comcast.net/~crmont/begin_purge.mpg Edit: (mpeg1 14meg)
http://home.comcast.net/~crmont/hose_connections1.jpg
http://home.comcast.net/~crmont/hose_connections2.jpg
http://home.comcast.net/~crmont/hose_connections3.jpg
http://home.comcast.net/~crmont/hose_connections4.jpg
http://home.comcast.net/~crmont/hose_connections5.jpg

Please reply if you have questions.

[MBDFahrer]

I don't have a 99 E300, but I was just wondering how did you cap off your lines from the fuel tank to prevent fuel from spilling all over the floor?

[crmont]

Once you hook up the lines as shown, the IP is isolated from the tank. There is no external or in-tank fuel pump on this car. You might want to make sure the tank is not completely full. (if you had a e300td that is)

[crmont]

The simple answer is you don't have to cap off the supply and return lines. I did however spend a few hours learning how the fuel system draws through the filter assembly. I hooked clear plastic lines to the car's fuel system and submerged them in a can of diesel so I could see how the system worked. The fuel in the disconnected lines actually drains back to the level of the fuel tank.

[MBDFahrer]

cool, wonder if that is just a theory for a 87 300D or if its the same concept

[crmont]

There is lots of info on this site reguarding your car. Do a search. Here is one link I found;

Quick question on diesel purge of your car

I've gone diesel in the past year, brought on by a change of life where my wife and I went from driving two blocks from home to our own business to our commuting a combined 800 miles per week to Albany for jobs as a result of a 2 year military activation on 9/11/01. I had a Dodge Cummins p/u, and loved it, so we sold the Suburban and an old Wrangler and bought an 03 Jetta TDI locally (great shape, 28,000 miles, my daughters named it Liesel the Diesel), and found a 99 Mercedes E300 Turbodiesel down in Connecticut on Cars.com (PERFECT condition, white, 45,000 miles, which my daughters immediatly dubbed "The Princess") to cut down on fuel costs, and with the ultimate goal of making our own biodiesel. Thus began my education in diesel care and maintenance.

Just found this website and forum, and have been digesting everything applicable to keeping the Princess in top form. BTW, great site and forums!

Anyway, with the foregoing as introduction, I found your thread on purging a 606 turbodiesel just as I was about to throw a couple of cans of newly arrived Lubro Moly Diesel Purge in the fuel tank. The process looked straightforward, and today was one of those extremely rare 60 degree days in February in Upstate New York, so ambition overcame caution - with the usual results.

I removed the return line from the main fuel filter, as shown, and everything was running in greased grooves until I tried to remove the plastic tube on the intake to the inline filter. No Go. The clear plastic tube would not budge. I then tried to remove the other end from whatever that expensive looking apparatus is under the manifold (what is that, anyway?). No luck with that, either. It is probably the original fuel line, and has become hard and stuck to the nipples. I spent a couple of hours trying to cajole that tube without luck. Knowing I was 40 miles from an MB dealer in the event that I broke either the fuel line or the expensive-looking thing on the other end, I decided to try another tack.

Another post mentioned disconnecting the feed and return lines by the firewall, so I redirected my efforts there. Since I already had the return line good to go per your plan, in theory all I had to do was disconnect the feed line at the firewall, cobble together some sort of union between the black rubber fuel line and the clear purge line that came with the Lubri Moly, and I was in business. But the fuel line was held tight by some strange German hose clamp that defied loosening. After an hour, I just broke the sucker off and made my first trip to NAPA for new hose clamps. That is when I discovered the meaning of your caveat to not have more than half a tank of fuel - I had just topped it off that morning before deciding to get into this project. Diesel fuel immediately began spewing all over. I tried to fit the Lubro Moly purge hose onto the supply line so I could pinch it off and hold it with a clamp to stop the leak, but it wouldn't fit over the nipple on the end of the metal fuel line. Another trip to NAPA to buy a piece of rubber fuel line that I could fit over the metal supply line, and that I could plug with a bolt or large Philips screwdriver. Since there was no size printed on the exisiting fuel line - just an MB part # - I bought a foot of 5/16th" diameter hose, only to find it wouldn't fit either. Back to NAPA for a foot of 3/8", the largest they had - still too small. At this point, my 1 hour project hads balooned to 6, it was pushing 5pm, clouding over and temperature dropping - not to mention I was supposed to be in bed by noon as I work midnight watch. So everything was returned to original condition and retreat was sounded, as I limped from the scene of my ignomineous defeat at the hands of German engineering.

So, that was my experience, here are my questions:

1. Is there some neat trick for removing hardened and stiff plastic fuel line from plastic nipples without breaking expensive attached parts?


2. What the heck IS the diameter of the rubber MB fuel line? Do I have to go to the dealer to get some that will fit?

Any help is greatly appreciated. No big rush, the next 60 degree day will probably be in June!

[crmont]

(Better late than never) The little white clips on the fuel line fittings are a release mechanizm that allows you to remove the fitting completely.

[phinphan]

Just wanted to thank the OP for the original thread and pictures. I completed my diesel purge cycle this evening. Took about 10 minutes to get the lines off and the temporary lines on. I used 3/8" on the pre-filter side by removing the plastic from an old fuel line and just using the tab that inserts in the top of the prefilter. I used 1/2" on the back of the filter housing as in the pictures. Worked great and the engine runs and feels a good bit smoother tonight. It might be wishful thinking but I hope it helps.

[crmont]

It takes 20-30 days before all of the little air bubbles in the fuel lines go away.

[nhdoc]

I just did a diesel purge on my '98 today for the first time. I used an old used fuel line for the fitting at the prefilter too, just cut it off and attached a piece of flexible fuel hose to it to use as the feeder and another piece of flex hose as the return line off the other "T" fitting.

It did quiet the knocking I was seeing at idle, at least it has so far, I will know better in a few more days driving though. The returning purge solution was very clean as it circulated...I know some people have reported the solution turning quite dirty but not in this one, it came back about as clear as it left. I guess that's a good sign that the fuel system is very clean.

[Parrot of Doom]

I wonder, whats wrong with pouring the stuff directly into the tank?

[TMAllison]

Is designed to be run through full strength. Can be used in the tank but wont work as well.

[TwitchKitty]

Originally Posted by Parrot of Doom

I wonder, whats wrong with pouring the stuff directly into the tank?

You could pour it in your petunias and it would help your car just as much.

Originally Posted by winmutt

Question. Once you were done with the purge did the noises come back? I think I am going to buy a gallon of purge and run through the whole container.

For this price you could actually fix your car the way the factory manual says to.

Originally Posted by TwitchKitty

The real cure for any Diesel Purge related problem is to avoid the product. I have posted the MSDS sheets and ingredients and the uses of the ingredients before. Don't waste your money. I posted about the attempts of standards organizations to set standards for this and similar products, they dropped the project. I have asked for anyone to post the name of any diesel engine manufacturer who recommends this product or any other like it. Don't waste you money.

If you have injection problems read the manuals by Mercedes or Bosch and fix the problems. Throwing money at the problem will not make it go away.

Another member here who is a Bosch authorized service center posted that Diesel Purge may actually damage your injection system.

It is a high profit item with little or no value for use in your car.

Stand by for anecdotal information to dismiss this post.

Still amused at the futile efforts to deny proper maintenance of diesel injection systems.

[winmutt]

Question. Once you were done with the purge did the noises come back? I think I am going to buy a gallon of purge and run through the whole container.