Diesel Fuel Additive of Choice? - Page 2 - PeachParts Mercedes-Benz Forum

aklim · #16 05-20-2008, 08:38 AM

Quote:

Originally Posted by rcounts

When ULSD became the standard a little over a year ago, they started dropping like flies, and I had a reman that failed on my truck with less than 100k on it. Given the price of the pumps (the single most expensive part on the whole engine) and the cost for new injectors (a set is probably the second most expensive part on the engine) I ran some numbers and decided that even if I added a nickel's worth of addative to each gallon of fuel, it was cheap insurance.

But hey, some people believe in buying insurance, and some don't.

BUT, rather than rehash old arguments, lets get back to the original question. What to use to clean the injection system? Surely you will agree that over time regular diesel will leave behind some varnishes and gummy residues that need to be preiodically cleaned out?

Ah, but why did they fail? My IP failed because the O-rings shrunk. Now, new O-rings and life is good. The pump is still fine after 120K of ULSD. The local diesel shops have made up their own "kits" for just that reason. Will additive help? Probably not unless it puts sulfur back so the fuel doesn't leach out the sulfur in the O-rings. Besides, there are quite a few diesel engines out there. If the lack of lubricity was a problem, don't you think they would be lined up for miles at the diesel shop waiting for repairs all day long?

I believe in buying insurance. However, I'd like to see more details on the insurance. I want to see what happens with and without before I decide to buy. So far, nobody has been able to show what lubricity factor is needed and what the point of diminishing returns is. I'm into buying insurance. I am not into dumping money into something in hopes that it works.

I'm not sure it does. Has there been issues with that where we need to address it or is it just something people think could be an issue?

aklim · #17 05-20-2008, 08:41 AM

Quote:

Originally Posted by rcounts

NOW can we get back to the original question of how to clean out and maintain a clean injection system.

I haven't seen that many issues of gunk in the IP. I think it is because the orifices are a lot larger than the injector orifices. Just my theory. I do know that the fuel injectors have had problems once it gets some miles. I took mine out at 100K, had them bench tested and found 1 dirty injector. They took it apart, cleaned it and it was back to normal. I prefer to test the injectors because then I KNOW that they are working in good order.

aklim · #18 05-20-2008, 08:46 AM

Quote:

Originally Posted by rcounts

So, should this be done once a year, once every 10k, 25k, 50k or at what interval? Seems simple enough, but I'll wager it is something that could be overdone and do some damage (Diesel Purge may be a great cleaner, but I'm thinking it probably isn't the greatest of fuels for a steady diet).

What about between "treatments" - any recommendations other than the occaisional "Italian tuneup"?

I would say it is difficult to predict. After all, you don't know whether you are over doing it or under doing it. I had one injector with low pop off pressure and poor spray pattern after 100K. Now if I had 4 or 5, I'd be nervous. However, at 1 injector in 100K, I am willing to look on it as an anomaly. I will take it out after 100K which will be sometime this summer to check.

Total cost for this check and cleaning was $70 for the injectors itself, Injector seals and some hose for the return line. About $100 give or take.

aklim · #19 05-20-2008, 08:48 AM

Oh yes. Additive of choice? None. Saves money and hassle.

#20 05-20-2008, 09:14 AM

Quote:

Originally Posted by aklim

Oh yes. Additive of choice? None. Saves money and hassle.

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