I have a compact diesel and am in need of more power.I also find that the diesel fumes tend to make me nauseous when the wind blows them in my face for anylength of time. Wearing a respirator is not particularlypleasant when when the mercury hits 120 for a week or so. I have thought about getting a larger tractor and converting itto propane power. The only conversion kits I have seen arefor gas powered engines which use a carburetor.Questions:Were there any 20-25 hp tractors built with gas enginesand 4wd (I haven't seen any, at least not that I recognized).Is anyone aware of whether a diesel could be converted topropane? (I assume it could be done, but might require usinga carb instead of direct injection.)I know a lot warehouse fork lifts use propane power, but don't know if any have the basic engines that allow aninterchange of parts to normal tractors. What is the desired compression ratio for a propane engine(I assume it is higher than for gasoline engine.) Has anyone tried this type of conversion?(I am aware that conversion to propane will normally lead to aloss of power of 7-10 hp or slightly more.)
Ain't no way in hell fool!!! Go to your local high school and take a basic auto shop class. Maybe you can learn the difference between gasoline and diesel engines.
It would be difficult to go from diesel to gas. You would need sparkignition, a different carburation system, lowered compression, and a differentcam since the valve duration is so different. Most propane engines start as gasoline, not diesel. What I did on my small diesel was to extend the exhaust pipe about another 4 feet up into the air using thin-walled steel tubing....OK, OK, I'll confessthat it was actually the long chrome plated tube off of my wife's old vacuumcleaner. I'll bet you already own one! Just the right size and weight. I paidguy at the muffler shop ten bucks to make me an adapter piece which fits ontothe stock muffler and them the extender pipe slides over it. Hose clamps providesufficient rigidity. Now my exhaust gets thrown far above my head and I don'thave to smell it anymore. The stock unit was right at eye level.What a truly dumb design that was! .............Roger L.
Couldn't have said it better myself Norman. Seems to me LEE should be the onevisiting his local high school,& take the "basic 7th grade" English class. Then, then sign up for the Army to learn a little respect & a few manners..OK LEE, Lets lets show all the boys & girls how to be grown-ups...Follow along.Casey,You didn't mention the make or model of your compact, nor did you mention how many hours have been spun on the meter. If your compact has quite a few hours on the meter,and you continue to see smokeafter initial start-up, you may consider having a tune-up. Secondly, try premium Diesel if it is available in your area.Hopefully you haven't been using the "cheap" fuel, that is available at certain stations.This cheap fuel will cost you more in the long run, and IMHO tends to smoke/smell more. Even if a PROP Conversion kit for a diesel existed, I could not imagine spending the money for what it would probably cost. Roger mentioned an inexpensive,do it yourself idea for very little $.Its worth a try..
Thanks for the responses. My current tractor is a Yanmar 155Dwith the side exhaust. It has about 800 hours and produces almostno visible smoke when warmed up. My place is in a canyon which gets swirling winds, so I find that even with tractors with extended exhaust pipes, I end up breathing a lot of diesel fumes.Every since I was a little kid and used to get very car sick whenfollowing diesel trucks, diesel fumes and I have not gotten along very well. Also, the recent classification by the EPA of the particulatesof diesel smoke as a known carcinogen do nothing to increase my desireto inhale diesel smoke. This 15hp Yanmar is under powered for my needs and I need to upgrade.As a friend and I buried his full size Farmall tractor up to the rearaxle when trying to snake logs out of his wood lot in damp conditions,I would prefer a 4wd machine but want something relatively compact.Thus my request for any information on used gas powered 4wd tractorsin the mid 20hp range. I have always liked propane power, so I wouldconsider converting the gas engine, although I assume that it would probably not be cost effective to do so.
I will simply assume that Lee was having a bad hair day rather thanconcluding that he was following the tradition of closing his mindbefore finding out the facts. I do have a smattering of knowledge regardingthe differences between conventional gasoline engines (i.e. modified Ottocycle engines utilizing spark ignition with throttle plate restriction ofair intake for varying power) and conventional Diesel engines (i.e. modifiedDiezel cycle engines utilizing direct fuel injection into gases heatedthrough compression for ignition and which vary the quantity of fuel injected for varying power.) Of course, as Lee undoubtely knows,the two types of engines share the isentropic compression, isentropicexpansion, and isochoric liberation of heat cycles and thus are differentiated by whether combustion cycle is a constant volume or a constant pressure process.While #2 diesel is the popular choice forfuel for diesel engines, any fuel which could be injected and which willignite at the temperatures generated during the compression stroke could theoretically be used. Granted, getting proper ignition from injecting a low energy density gas such as propane would be much more difficult than utilizing a high density fuel such as #2 diesel. My thought was that given the narrow range of flammability of Propane, that through introducing some Propane into the intake air through use of a propane carburetor, that one could then inject directly into the cylinder the remainder of the fuel requiredto attain the required fuel air mix for combustion. Of course, I considered it unlikely that anyone had gone to this much trouble, but thought I would throw it out - perhaps if the Propane was keptliquid until it was sprayed into the combustion chamber, enough couldbe introduced in a short enough time to make it actually work.Unfortunately, in truncating my comment, it probably did appear that I didn't have a clue...Having helped develop the teaching materials for a course on auto mechanicsfor a community college, I can say that at least that course did not getinto sufficient detail about diesel engines to shed much light on whetherPropane fuel could be adapted for use in a diesel. Of more help wouldbe an engineering course on thermodynamics where they usuallycontrast the Otto and Diesel cycles and calculate the variousefficiencies and entropy vs pressure relationships of the various cycles.Unfortunately, I took my thermodynamics class in the physics departmentrather than engineering, so I didn't get much of that. So, maybe Lee could help - I always had trouble with calculating those entropy relationships for isochoric vs constant pressure heat transfer;perhaps Lee S. could give me a short tutorial to help me out on this...