Gents,


What is the consensus or opinion for periodically adding Marvel Mystery Oil to your D-Max's Diesel fuel (pre-filling the tank) as an additive for fuel system lubricity and keeping things (internally) clean? I was told by a diesel service mech (not GM)that this is advised and a good thing for lines, pump, rail, regulator, injectors and combustion chambers. Ya'll's thoughts on this? Thanks.


Mudbug

I've read here that the older low pressure injection systems seemed to do fine with Marvel Mystery type additives but with the advent of high pressure common rail systems its a big no no.


Do a search and you will find alot of negative feedback on adding tranny fluid and other "old timer" tricks to your diesel fuel.Pay special attention to what George say as he is the accepted expert on fuel related issues on this site and others.


Welcome to the "Place".http://www.dieselplace.com/forum/smileys/Hug.gif


Blake

Small to moderate doses of MM to the fuel system will not hurt a thing and will add some lubrictiy.

My understanding is that MMO is basically a solvent... IMHO, I don't think it's good for our fuel system. It has some other uses but not in my duramax diesel fuel tank.


For more info - and spirited discussion - try seaching the BITOG (http://theoildrop.server101.com/ubb/ultimatebb.php) Additive forum for "Marvel Mystery" I did a seach and got 41 hits..


Also, for those who haven't seen it, heres a link to GM's position on Diesel Fuel Additives (http://service.gm.com/gmtechlink/images/issues/apr03/TLApr03e.html#story1)


http://www.dieselplace.com/forum/smileys/Geek.gifEdited by: jbplock

Gents,


Thanks for the feedback on this one. Much appreciate it.


jp, that was some 'spirited discussions' on BITOG.


Mudbug

Bitog is a great site.

Gents,


One more time, here. JP (and all), your comment on Marvel Mystery Oil being a solvent; Isn't diesel fuel, in and of itself, a widely used solvent?


Not being a smart azz with the question back to you but that thought just struck me. Again, this is only as it would apply to a D-Max (with its high fuel delivery pressures), not other brands of engines.


Any comments or thoughts on that? Thanks, guys.


Mudbug

Mudbug,

I'm not a chemist but it's my understanding that diesel fuel is more of an oil (fuel-oil) than a solvent. I think adding a solvent to diesel fuel(oil) would tend to make it "thinner" and further decrease it's lubricating properties (which are small to begin with and getting less with low sulfur fuel).

Is there a chemist in the house who can give a better answer? http://www.dieselplace.com/forum/smileys/Confused.gif

http://www.dieselplace.com/forum/smileys/Geek.gif

I had a friend who used a 50/50 mix of Marvel and motor oil in a POS Saab that had a bad rap. Quieted the rap, and ran it for 75k mi before it hemmorhaged a rod...


Obviously a 4-banger crankcase and a common rail fuel sytem are two COMPLETELY different birds...


Ty