2 cycle oil diesel additive? - Page 4 - PeachParts Mercedes-Benz Forum

mach4 · #46 06-07-2017, 04:31 PM

Quote:

Originally Posted by OM617YOTA

Edit: Nevermind, I really need more coffee. Wow.

Good choice! Coffee is always good.

I was going to ask about your favorite coffee additive, but nevermind!

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97 SL320 · #47 06-07-2017, 07:29 PM

Here are a few thoughts.

Is there even enough sulfur in traditional diesel to provide substantial pump lubrication?

Sulfur is more or less a dry film / high pressure lubricant that is also used in hypoid gear lube. This is done because the pressure between gear teeth squeezes all of the oil out but sulfur sticks to the surfaces preventing metal to metal contact.

I'd expect diesel pumps to have some points of high pressure, the questions would be: Are forces high enough that sulfur is needed? If forces are high, will conventional oil / additives help anything?

Squiggle Dog · #48 06-07-2017, 09:56 PM

I have actually heard a few times from forum members, mechanics and injection shops that they are experiencing injection pump failure due to the new diesel not having as much lubricity. Same problem as many new oils no longer having phosphorus or zinc--the parts wear out faster.

I personally have only experienced one pump failure, and that was likely caused by polymerized waste vegetable oil. When I acquired the car, I did a diesel purge and after the polymerized oil cleared out, the pistons leaked badly enough that the engine filled up with so much fuel that the oil level came up into the valve cover and hydrolocked the engine.

Apparently the sulfur in the old diesel had lubricating properties. If this is true, I don't know, but I run biodiesel as much as possible and that more than compensates for any loss of lubricity.