| Author | Message | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 361 Registered: 10-2006 Posted From: 208.100.193.125 Rating: N/A |
Years ago there was a rush to stick propane injection on diesels to increase power (hill climbing ability). Now in some truck rags I see propane being touted to increase mileage . In this case a small amount is used almost constantly. Any comments? FF | ||
| Debbie and Joe Cannarozzi (Joe_camper)
Registered Member Username: Joe_camper Post Number: 98 Registered: 10-2006 Posted From: 71.239.202.82 Rating: N/A |
There are no definitive answer about doing that to a 2-stroke diesel. Would you like to be the Ginnie pig. | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 93 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
Not only does it work, it works quite well, a lot of fuel is used to clinb hills, the less time climbing is fuel saved.>>>Dan (been doing it for ten years) | ||
| Ednj (Ednj)
Registered Member Username: Ednj Post Number: 194 Registered: 3-2003 Posted From: 67.85.229.150  Rating: N/A |
Fred, They have been doing it for years here on this site = http://www.thedieselstop.com/ , do a search for propane. I know its pickup trucks but good numbers anyhow. 20lb propane every 400 miles for a 2-mpg gain. Here is another good read for you = http://www.dieselsite.com/index.asp?PageAction=VIEWPROD&ProdID=186 That s a 203 degree Thermostat. | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1306 Registered: 12-2000 Posted From: 76.66.19.238  Rating: N/A |
Excellent idea to be pursued here! How big does the cost split per BTU between propane and diesel have to be for a return on investment? Re: the 20 lbs of propane used over 400 miles to achieve 2 mpg improvement... of most importance, what methods/equipment were they using to measure this? How much fuel in gallons did it save in that application, versus the cost of 20 lbs of propane? I'm thinking that if there is a payback, the time may be too long for a typical busnut's annual travel, but then the engineering experiment is usually our primary goal, not $$$$!!!! For the casual observers, the goal here is to find a way to use a fuel that is cheaper per BTU to help get us down the road. As with any "savings program", if the costs of the project can't be paid for by the savings, you won't be happy at the end! happy coaching! buswarrior | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 459 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Here's 3 facts: 1. 94,600 BTU in a gallon of propane, which weighs just over 4 lbs/gal. 2. 144,000 BTU in a gallon of diesel. 3. Horsepower is calculated by the work performed in an amount of time. (The less time consumed to do the same amount of work=more horsepower.) What am I getting at? Say we climb a small mile long hill at 1/2 throttle. Our tires are 500 turns per mile, we are in high gear, which is direct drive, and we have a 4.00 differential. That means the engine will turn 2000 revolutions going up the mile long hill. So we INJECT HALF OF THE INJECTORS' RATED FUEL DELIVERY PER STROKE, FOR EACH OF THE 2000 strokes. Now we go up the same hill faster at full throttle. IT STILL TAKES 2000 STROKES, like it or not, but the fuel consumption will be DOUBLE. Does this mean not to speed up so you don't run out of gas before you get to the gas station? Yup. G | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 94 Registered: 1-2005 Posted From: 208.66.38.115 Rating: N/A |
George, your statement does not include another fact,,,,,,,most of our two strokes wont climb the hill without "full" throttle.>>>Dan (and even a lower gear) | ||
| Kyle Brandt (Kyle4501)
Registered Member Username: Kyle4501 Post Number: 427 Registered: 9-2004 Posted From: 65.23.106.193 Rating: N/A |
It occurs to me that -IF- one wanted the huge HP to climb hills & accelerate, this propane injection would be cheaper than repowering & having to feed all those thirsty horses ALL the time. I did notice that my 4501 did best when driven in it's 'sweet spot' & there was very little performance difference between full & 3/4 throttle hill climbing. Yes, she'd run almost 80 against the gov. But ~3/4 throttle yeilded 60 to 65 & she didn't labor much on the hills. If I drove at 50 to 55, she was constantly struggling & lost lots of speed on even the smallest of hills. | ||
| Don Evans (Doninwa)
Registered Member Username: Doninwa Post Number: 121 Registered: 1-2007 Posted From: 208.81.157.90  Rating: N/A |
Dan, As a long term user do you find the propane to have a catalyst effect? I hear some claim the propane improves the burn and gives better overall efficiency. Or is it just for added power? Do you inject only at high power or some at cruise too? Thanks, Don 4107 | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 95 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
From what I have read on the subject there is some sort of catalyzing action involved, something like 70% efficientcy straight diesel and over 90% with propane mix. I know when I am climbing at a given rpm with the switch on and shut it off It looses rpm dramaticaly and would require a shift, I can turn it back on and rpm will return.>>>Dan | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 767 Registered: 12-2000 Posted From: 76.3.173.51  Rating: N/A |
Dan, I am interested in more information about your LP injection system. Is this a "factory made" or "home brew" system? How bout a general description of the system. Thanks Jack | ||
| Moe Hollow (Moehollow)
Registered Member Username: Moehollow Post Number: 32 Registered: 12-2007 Posted From: 71.102.28.116 Rating: N/A |
I am not sure about increased mpg, but am interested in it for hill climbing boost. | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 461 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Dan, Having had my bus for 22 years now, I am well aware of what it takes to get it up a hill. And regardless of what Tom says, an 8844 is not the perfect trans! I don't want to be picky, but this was a discussion of fuel economy, and applying more throttle than necessary lowers fuel economy instead of increasing it. George | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 96 Registered: 1-2005 Posted From: 208.66.38.115 Rating: N/A |
George, you are correct on the throttle for sure, my point was a dramatic increase in fuel consumption while climbing hills and long grades can be reduced with the use of a propane mix that will elliminate a gear reduction and a longer than needed pull.>>>Dan | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1175 Registered: 10-2003 Posted From: 71.58.110.9  Rating: N/A |
If you are looking for fuel economy, look elsewhere. How much do you want to invest in this to get slightly better fuel mileage with a looong payoff time? To me, propane injection looks like a great deal for power, especially on turbocharged engines. The cooling effect of the propane can also lower inlet air temps reaching the cylinders. Can run smaller injectors to reduce the smoke and increase engine longevity. | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 97 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
John, thats the great thing about a basic propane system, it does not have to be fancy with a long payback time. I have about $250.00 in mine and have been useing it for ten years trouble free. Several people have approched me at rallies & so forth and taken pictures ect ect and I know many that have devised a similar system and are enjoying the results.>>>Dan | ||
| JR Lynch (Njt5047)
Registered Member Username: Njt5047 Post Number: 255 Registered: 7-2006 Posted From: 69.132.233.230 Rating: N/A |
Does propane increase temp? A good many buses are limited during hill climbing by excess engine heat. Does LP have a cooling effect? JR | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 98 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
YES | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 772 Registered: 12-2000 Posted From: 76.3.173.51 Rating: N/A |
Dan, Yes, Propane does increase temmp or YES, LP does have a cooling effect | ||
| R.C.Bishop (Chuckllb)
Registered Member Username: Chuckllb Post Number: 301 Registered: 7-2006 Posted From: 4.240.141.142 Rating: N/A |
Dan.. like Jack, I am interested in knowing more. Got any pictures you could share? I am sure others would like to see them as well..  Thanx RCB | ||
| Moe Hollow (Moehollow)
Registered Member Username: Moehollow Post Number: 33 Registered: 12-2007 Posted From: 71.102.28.116 Rating: N/A |
As I understand it, since you are carrying propane anyway, there is not much cost. The simplest system I have read about just ran a line directly into the air intake and had a solenoid to turn it on/off. I do not know what psi you are looking for though. It supposedly works best with a turbo but is said to still give noticeable boost without one. One issue I could see would involve the placement of the solenoid. To get the quickest response, you would want it in the engine compartment. But it seems like it would be safer if it were closer to the tank. Maybe using two valves would work. | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 99 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
I use an acetylene regulator mounted close to the engine set at 15 Lbs. out, tank pressure in, then to a pair of 12V lock-off valves (solenoids) then to two #4 aircraft fittings threaded into the intake houseing above the blower>>>doesnt get any simpler than that, an "on demand system" >>>Dan | ||
| Moe Hollow (Moehollow)
Registered Member Username: Moehollow Post Number: 35 Registered: 12-2007 Posted From: 98.173.211.230 Rating: N/A |
Dan, It would seem that volume is more important than pressure, so one would be looking to balance line size with psi. How big a line did you use and how did you decide on 15 psi? Do you have a turbo? | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 466 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
A couple of more thoughts here, and its starting to get really scary! Propane weighs about 4 pounds per gallon, so 20 pounds per 400 miles (80 miles per gallon of propane) to give a 2 mpg diesel increase ON AN 8 MPG BUS would be great. This system is described as "then to a pair of 12V lock-off valves (solenoids) then to fittings..." WHAT HAPPENS WHEN YOU 1. Screw up and kill the engine by coming off the clutch too quick and its still feeding propane, and you re-start? BANG!! 2. You flip the switch by accident while stopped? 3. Your kids/grandkids flip the switch? 4. It feeds the same amount of propane whether idling or full throttle, that just doesn't make sense? With some control logic, it seems like the propane use could be cut WAY down, (see below.) 5. You crest a hill, and take your foot off the throttle. The gov moves the rack to the no-fuel position, but you continue adding full flow propane. Unlike diesel, propane won't ignite under high pressure/temp, it takes an ignition source, which returns at the bottom of the hill when the gov moves the rack back to supplying fuel. I guess if you're lucky, the wind will have blown it all away, except for what's in the eng, manifolds, turbo?, and mufflers(s), again, loud (and expensive) consequences. In my opinion, this system has to be wired in series through the system switch, not-gen relay, normally open terminals added to the fuel pressure switch, normally open terminals added to the oil pressure switch, AND a micro switch on the throttle linkage, all of which will open the circuit any time the throttle is closed, or anything else is not right. The closed throttle micro will keep the lpg off during Jake operation also. This might be one heck of a cold start system, but again, maybe not??? IMNSHO, nothing but an on/off switch makes it a one-person bus, and that one person hadn't better be the least bit inattentive! George | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 283 Registered: 2-2001 Posted From: 69.77.151.47 Rating: N/A |
Come on, George, They're ALL one person buses. If my wife drives 100 miles on a 2,000 mile trip, that's a lot. Maybe a better solution would be a key lock switch that activates the solenoid valve circuit. The bus's "one man" keeps that key on his person & removes it when leaving the driver's seat. Actually, for something useable by the general public a safety system would be adviseable. Why not add a little computer to decide if all conditions were "go" for propane? My pickup has computers to turn on the dome light, the air conditioner and the ignition key only tells the computer to start the engine. Can't have too many computers these days! | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 469 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Come on, Jim, They are all indeed one person busses. I know my post is long, but I went to great lengths to explain what I was getting at, AND a way to make it better, and use less propane. The original design flows one rate of propane whether the throttle is at idle or wide open, AND whether the Jake is on or off........... Please READ the paragraph which says: "The system has to be wired in SERIES through the system switch, not-gen relay, normally open terminals added to the oil pressure switch, normally open terminals added to the fuel pressure switch, and a micro switch on the throttle linkage, all of which will open the circuit any time the throttle is closed, or anything else is not right." IF THAT ISN'T A SIMPLE, CHEAP, FOOLPROOF COMPUTER, I don't know what one is! And you don't have to program it, reboot it, or give it a power supply, it doesn't use any power, on or off. It will NEVER have a logic lockup, and you can troubleshoot it easily with a voltmeter, or a test light. Using a key for the propane switch still won't turn off the propane when the engine dies, or when the throttle is closed, and no propane is needed. Sorry to jump on you, as I don't know whether you were being humorous or not, but IMNSHO, an accidental propane release isn't funny! Warm regards, George | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1191 Registered: 10-2003 Posted From: 71.58.110.9 Rating: N/A |
Good points George. If someone is going to install this system, then they should think out and plan the safeguards. Be a good setup with a coach with smaller injectors, to get that added power when needed. To install it to get better fuel economy, even if it improves it, doesn't make it worth the effort to me. I like the idea of the added power without the smoke though. |