Oh, but that diesel fuel looks so clean at the pump...
 

Hello all...reasons why the diesel purge is absolutely necessary on your Merc diesels and why your fuel filters need to be changed regularly!

The first pic is the purge bottle...it started out light amber colored.

The second pic is the filter element removed from the primary fuel filter!

30 minutes of preventative maintenance saves you from a world of hurt later!

focus!

seriously my 603 diesel had been knocking and I couldnt figure out what was causing it, I had tried some powerservice 'diesel kleen' awhile back, running the engine directly off that but it still knocked. my local advance auto now carries the lubro-moly diesel purge, after just a few minutes on one can, the knocking was gone!

Answer: none.

DP is just very expensive Diesel with some solvents added. Just because the fuel coming out turned black does not mean it was or will cause any problems.

what about the regular addition of Marvel?

If it makes you feel good, thats about all its doing.

I disagree. I've listened to injectors on multiple cars with a stethoscope and after running a can of diesel purge through things the injectors are quieter, and moreover all end up sounding even when before some were louder then others.

-Jason

It can also mean the needles aren't seating completely.

Sound isn't very useful, you would need to remove them and do a spray test to determine if there was any change (good or bad).

We just replaced the nozzles on my dad's SD with Monark nozzles this past weekend, and it did improve the motor's operation. Idles smoother, more torque, and rev's easier/stronger. Also, 0-60 has a much stronger feel, it pulls good again. Fuel in our area seems to be pretty clean. I've not touched a fuel filter on any of our diesels in a long while, and all of them are running fine. My primary and secondary have got to be going on 2.5 years/25k now....I'll probably change them when the weather is warmer....but my car runs perfectly fine still.

I think mystery oil does help a bit with providing extra lubrication to the injection system....but that's probably about all. I don't use it....my dad does sometimes.....it does make his run a little quieter. (Mine is very quiet as is.)

Occasionally I use Redline Diesel Catalyst for its water-removal properties....but that is all.

I've had thirty benzes over the last thirty years. Most of them high mileage diesels. I have never used diesel purge yet and probably will never. I just use decent fuel and keep the filters changed regularly.

My dad's SD had only 2 year old Bosio nozzles in it, but the inside of the injector already had some dirt and junk in it....I'm assuming from the fuel....pretty scary.

Bryan was going to test my old nozzles with some Dieselpurge and do an experiment - I'm not sure what came of that...

He posted results.

..or lackthereof

Purging is a very good practice if running wvo.But B100 would be better.

Bad fuel can plug filters as you pull out the driveway of the small out of the way gas station:eek:. (the kind with the diesel pump over in the corner, that nobody uses:D) I buy fuel at busy stations and don't change filters till they need to be. That is until I can feel a slight "miss" on a steep grade, there always seems to be many miles of driving on 'the flat" before any "miss" is noticed if its in the middle of the night. I dont think this is a good idea with the Dodge/Cummens, bad for the IP,I've heard.

I should add that I carry rubber gloves, a quart of CLEAN fuel or a can of purge to fill the secondary filter.

I disagree. The combustion event is going to make a sound. If the sound changes you can assume the combustion event changed.

I'll have to see if my buddy can score some time on the electron microscope at his work, pull one of the injectors on my TDI, look at it, do a diesel purge, and then look at it again.

-Jason