I think I remember a lot of guys recommending Marvels but I can't remember the thread. I'm wanting to add something to my diesel tank on my duramax that I've just converted to 65% natural gas. I'm now getting 43 MPG out of my diesel tank which means there isn't much lubricating the top end. 2 stroke oil would do the job but I'm worried about fouling injectors.

Marvel makes a specifically labeled diesel fuel additive. I have no idea if it is the same as regular MMO or not, but you can call them and ask. I saw the diesel Marvel product for $3.00 in a discount store called Big Lots (used to be Pic n' Save here in CA). If you have Big Lots near you it might be worth a call or visit to see.

I use a highly concentrated product called leyvan or somethin like that. Might be made by Lucas. I get it in a generic bottle from a guy thet gets it in bulk. It is a high detergent and lubricant.been usin it for 12 years. Never an injector or pump problem with my dodge 12 Valve. 225,ooo miles. I have a bulk tank and put in about 6 oz. for 250 galons of fuel.
Gary

I have not added any additive to my fuel in my 2000 Ford 7.3 diesel. But I have been using Locus Oil additive and the engine runs a lot quieter and smoother.

There is a lot of 2 cycle oil such as Yamalube run in the electronic diesels at 1 oz. per gallon without injector issues. Can't say for certain what the results would be with a NG mix but I bet it would be an excellent choice. I'd find a good diesel shop and ask them.

You can run anything in those 12 valve Cummins, even a percentage of used engine oil, although I forget how much. The pump and injectors are bullet proof. It's too bad they didn't put that engine in a real truck.

I would think that oil would be good enough. Using CNG or propane you've got less particulates or carbon which are abrasive.

I've looked into CNG kits a little and wondered about top end lubrication. What I gathered is that it is not really an issue. As long as the injection pump and the injectors are getting pure diesel then every thing is fine. If it were me I'd still want to add something just to make myself feel better. I've had good experience with MMO so that is probably what I'd go with. I might try bio-diesel because it provides better lubrication than regular diesel.

Where are you going to fill up at? That is the issue that stopped me; no where to fill up in Eastern Idaho and at home fueling stations were too expensive. What kit did you go with?

2 to 5 % biodiesel is about as good as it gets for lubricity. 2% in the new ULSD brings back everything that was lost when they removed the sulfur.

Thanks all for the feedback. Whee- I bought a ghetto rig from a guy in Salt Lake. It works well, dirt simple. It comes on at 2 pounds of boost and injects CNG into your intake tube, shuts off at 2 pounds so you don't chug at stop lights, $1400 with 12 gallon tank, added 100 unnecessary horsepower. I'm shopping for my own fill station but currently, my buddy is letting me sponge off of his scuba- tank- filler- retro- fit- pump. I'll pay for the kit in a couple months if it doesn't blow up, I figure 65% cng at 80 cents cuts my fueling bill in half.

Nosedragger wrote:Thanks all for the feedback. Whee- I bought a ghetto rig from a guy in Salt Lake. It works well, dirt simple. It comes on at 2 pounds of boost and injects CNG into your intake tube, shuts off at 2 pounds so you don't chug at stop lights, $1400 with 12 gallon tank, added 100 unnecessary horsepower. I'm shopping for my own fill station but currently, my buddy is letting me sponge off of his scuba- tank- filler- retro- fit- pump. I'll pay for the kit in a couple months if it doesn't blow up, I figure 65% cng at 80 cents cuts my fueling bill in half.

If ya don't mind PM the guys name in SLC. I've got an old lb7 dmax and you've sparked my interest. Looked into the scuba fill station a while back, kinda got scared off but I'm a chicken. Would be nice to run the truck, car and snowmobile on CNG though...

Nosedragger:

Can you give us a little more info. If you are getting 43 mpg, what were you getting before. And what is the blended cost of the CNG and diesel. How much did it end up saving you??

I drive around in an old 84 Mercedes Diesel that is still purring along giving me 25 mpg at 200,000 miles. However, I have been considering starting to make my own diesel. Diesel is just under 4.00 here and I put on quite a few miles each day.

Hadn't considered this alternative though.

Thanks in advance for the info.

Regards, Larry

Nosedragger wrote:Thanks all for the feedback. Whee- I bought a ghetto rig from a guy in Salt Lake. It works well, dirt simple. It comes on at 2 pounds of boost and injects CNG into your intake tube, shuts off at 2 pounds so you don't chug at stop lights, $1400 with 12 gallon tank, added 100 unnecessary horsepower. I'm shopping for my own fill station but currently, my buddy is letting me sponge off of his scuba- tank- filler- retro- fit- pump. I'll pay for the kit in a couple months if it doesn't blow up, I figure 65% cng at 80 cents cuts my fueling bill in half.

You can do a "roll your own" fill station by putting together some basic components... This place is a source for the boost pump. http://www.haskel.com/corp/details/0,10 ... 59,00.html.

Some FBO's are using those boost pumps to recover 97% of the available O2 out of the supply bottles... Before they would have to trade in O2 bottles when they got down to 1300 PSI... Now they get can draw the host bottle down to 100 PSI. They are saving a TON on O2 host bottle fills. The only one not happy is AirGas. They loved getting a O2 bottle back half full,, only to top it off again for the full price of an emply one.

Ben.

Stol wrote:

Nosedragger wrote:Thanks all for the feedback. Whee- I bought a ghetto rig from a guy in Salt Lake. It works well, dirt simple. It comes on at 2 pounds of boost and injects CNG into your intake tube, shuts off at 2 pounds so you don't chug at stop lights, $1400 with 12 gallon tank, added 100 unnecessary horsepower. I'm shopping for my own fill station but currently, my buddy is letting me sponge off of his scuba- tank- filler- retro- fit- pump. I'll pay for the kit in a couple months if it doesn't blow up, I figure 65% cng at 80 cents cuts my fueling bill in half.

You can do a "roll your own" fill station by putting together some basic components... This place is a source for the booth pump. http://www.haskel.com/corp/details/0,10 ... 59,00.html.

Some FBO's are using those boost pumps to recover 97% of the available O2 out of the supply bottles... Before they would have to trade in O2 bottles when they got down to 1300 PSI... Now they get can draw the host bottle down to 100 PSI. They are saving a TON on O2 host bottle fills. The only one not happy is AirGas. They loved getting a O2 bottle back half full,, only to top it off again for the full price of an emply one.

Ben.

Wow! Thanks Ben, those kind of resources are hard to find.

88H wrote:Nosedragger:

Can you give us a little more info. If you are getting 43 mpg, what were you getting before. And what is the blended cost of the CNG and diesel. How much did it end up saving you??

I drive around in an old 84 Mercedes Diesel that is still purring along giving me 25 mpg at 200,000 miles. However, I have been considering starting to make my own diesel. Diesel is just under 4.00 here and I put on quite a few miles each day.

Hadn't considered this alternative though.

Thanks in advance for the info.

Regards, Larry

I didn't see your post on the first round Larry. If you're not turboed then I can't say how this kit I have would work, but if you are, and you have room in your car for an extra tank, they work. The Pig in the Python in most places is finding a place to refill. If you buy your own station and can hook your car up overnight, a slow fill station costs about $5k, lasts 5000 hours, pumps a gallon an hour and costs you whatever the rate is at your meter (.62/therm for me). If you have a refill station in town, they usually make 75 cents a gallon for the fast fill pumping convenience. I got 19 MPG in my Duramax on straight $4 diesel, 43 now on approx. a $5 gal. blend.

Thanks for the info.

I am turboed, but it still looks like converting grease is a cheaper option.

i am investigating now and will keep you posted on how it goes.