AC D17 on propane
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=145774
Printed Date: 05 May 2025 at 7:47am
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Topic: AC D17 on propane
Posted By: TomYaz
Subject: AC D17 on propane
Date Posted: 23 Dec 2017 at 5:43pm
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Guys, Looking into converting the D17 to Propane...Mount a tank, put on the hardware. Looking at this: https://www.ebay.com/itm/COMPLETE-IMPCO-PROPANE-CONVERSION-FOR-ALLIS-CHALMERS-TRACTOR-WITH-UPDRAFT-CARB-/181970630989" rel="nofollow - https://www.ebay.com/itm/COMPLETE-IMPCO-PROPANE-CONVERSION-FOR-ALLIS-CHALMERS-TRACTOR-WITH-UPDRAFT-CARB-/181970630989 I see the carb there, but on the other two...one is a fuel regulator, what is the other piece? the vacuum shut off? Any thoughts? Tom ------------- If its not an All-Crop, it all crap! |
Replies:
Posted By: TomYaz
Date Posted: 23 Dec 2017 at 5:48pm
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Ok sort of found the answer, One is the pressure regulator, the other a converter. Convert the liquid to gas... Where does the vacuum shut off come into play? I understand there is the electric type and vacuum.. Tom ------------- If its not an All-Crop, it all crap! |
Posted By: DrAllis
Date Posted: 23 Dec 2017 at 6:13pm
| Now, you realize you will not have 53 HP anymore, right ?? Probably about 48 or 49 HP unless you increase the compression ratio up to 8.0 to 1. |
Posted By: TomYaz
Date Posted: 23 Dec 2017 at 6:30pm
Ya I will be fine.. Doing more studying...so that converter...is a Century C-J...takes coolant to heat the liquid propane to turn it into gas....Now my understanding is a tank like a 20 pounder will be 20% gas, rest liquid. When we use it for the grill for instance, we don't need to heat the liquid. I take it that is because the liquid is becoming gas faster than it is being used. On the tractor, I'm thinking we could hit the liquid portion faster than it can turn to gas inside the tank-requiring the heating. Am I getting this right? Tom ------------- If its not an All-Crop, it all crap! |
DrAllis wrote:Posted By: JC-WI
Date Posted: 23 Dec 2017 at 6:37pm
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Tom, what are you going to use for a tank? Maybe just watch for a D17 on propane already... ? ------------- He who says there is no evil has already deceived himself The truth is the truth, sugar coated or not. Trawler II says, "Remember that." |
Posted By: TomYaz
Date Posted: 23 Dec 2017 at 6:38pm
Mount one on the side. ------------- If its not an All-Crop, it all crap! |
Posted By: Gerald J.
Date Posted: 23 Dec 2017 at 7:43pm
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The operating procedure for a LP JD 4020 is a little bit complicated. From the manual as I remember it. i don't have an LP tractor. There are two feeds from the LP tank, one gas and one liquid each with a shutoff valve. When parked both valves are to be kept closed. For a cold start the gas valve is opened then the engine is cranked and run at a fast idle until the coolant is warmed up. Then the liquid valve is opened and the gas valve closed. The converter is warm enough to vaporize the liquid LP. There isn't enough gas in the tank to do work on gas alone. Then to shut it down for parking, turn off both valves and run the engine until it is out of fuel past those valves. You never want to open the liquid valve without the converter hot because the LP carburetor is based on gas, not liquid and the engine won't run on liquid LP. There was a connection on the gas line of the 4020 to allow connecting a BBQ tank used by the factory to run the tractor from the assembly line to the truck and by the dealer to unload the truck with the LP tank on the tractor empty. And on the farm to run the tractor back to the LP filling station when it ran out of LP in the field. There is a size of LP tank that will naturally vaporize enough liquid to run any given engine, but its bigger than the typical tractor (the whole tractor). My Onan with Continental Y91 by a LP utilization handbook I have would have to have a minimum 250 pound tank to produce a mere 10 hp for a 5 KW generator. Gerald J. |
Posted By: JC-WI
Date Posted: 23 Dec 2017 at 8:17pm
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On our old WD, we were told to run on liquid to prevent burnt valves, but after the first year, we just left it on vapor, that was 56 years ago. When the tank got down to 10% on them 15 degree or below days, there wasn't enough fuel vaporizing to produce the hp to pull the hill to get home in high gear. When working at a peat plant, we were using some serious vapors off of two 100# cylinders (experimental dryer) and we tipped them about 50 degrees over from verticle to get more surface for the propane to vaporize... and in mid summer, they were icing up so bad that they would quit vaporizing and had to use a third tank with a weed burner pointed at the other two to help keep the pressure up. LOL Now days, they are working on using Liquid propane direct injected into the engines like they do for diesel... Back to the D17, maybe watch for a running LP D17 ...jmo. But will tell you that I want to set up a WD45 with propane like our old WD.   This D17 was for sale back in may.  ------------- He who says there is no evil has already deceived himself The truth is the truth, sugar coated or not. Trawler II says, "Remember that." |
Posted By: JC-WI
Date Posted: 23 Dec 2017 at 8:40pm
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Gerald, the JD set their tank on end and mad for less vaporization unlike IH and oliver running long tanks horizontal. and over the engine made for more heat to vaporize too. The propane tank on this WD was on vapor since about 1961, even when plowing, You could turn the liquid on and shut the vapor off and made no difference. at least that was our experience... until you hit that 10% mark then it did. Many times we came home in the summer with the needle hanging straight down, that was different becuse it was hot out. There was a fellow in the community that had a 190XT LPgas... and in the winter he fought with it all the time trying to start it. Even with a torpedo heater under it. Tried to tell him to shut the valves off till it died and then turn the switch off and then when starting it, turn just the vapor on and hit the switch and let it warm up before turning the liquid on and shutting the vapor valve off... but he said he shouldn't have to do that. Was the sweetist running XT I ever heard idling or working., but he decided it had to be turned into a diesel, and a few years later, it looked like it had been through a war, beat to death. ------------- He who says there is no evil has already deceived himself The truth is the truth, sugar coated or not. Trawler II says, "Remember that." |
Posted By: TomYaz
Date Posted: 23 Dec 2017 at 9:01pm
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Interesting stuff fellas... So I guess that Century CJ converter will ensure I was always running vapor.... Here is a guy that VERY crudely converted to vapor.....not sure I would have any open flame around that connection to the air cleaner. https://www.youtube.com/watch?v=TEDxPAUyLnU" rel="nofollow - https://www.youtube.com/watch?v=TEDxPAUyLnU ------------- If its not an All-Crop, it all crap! |
Posted By: AJ
Date Posted: 23 Dec 2017 at 10:07pm
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I have a nice factory correct LP carb for the D17 if you get deep in the project. ------------- Can't fix stupid |
Posted By: TomYaz
Date Posted: 24 Dec 2017 at 4:14pm
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PM sent ------------- If its not an All-Crop, it all crap! |
Posted By: Dennis(IA)
Date Posted: 24 Dec 2017 at 5:21pm
| Dad had a '66 190 XT on LP and that was a great tractor. Never had problems starting in the winter. Only problem was that the distributor cap liked to make a carbon path to another cylinder. That was because of the high compression. |
Posted By: DaveKamp
Date Posted: 24 Dec 2017 at 6:19pm
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Tom- To clear up some misnomer: Propane is a hydrocarbon fuel: C3H8 Liquid propane doesn't burn. Only vaporized propane, mixed with oxygen (air) will burn. In the tank, it's stored as liquid, where the vapor pressure is such that it remains a LIQUID below about -44F. At any temperature ABOVE -44, it will evaporate UNTIL the pressure within it's containment reaches a corresponding level. Here's a few examples: -20F = 11psi 0F = 24psi 30F = 51psi 60F = 92psi 80F = 128psi 110F = 197psi Now, it's 0F outside, you'll see 24psi on a gauge, but if you start to relief VAPOR from the tank, the tank pressure will drop, and contents of the tank will boil. Now, it will only boil so fast... and the rate at which it will boil off more vapor, is determined by how QUICKLY the tank can absorb ambient heat AND... how much SURFACE AREA is available for boiling. IF the tank doesn't have enough ambient heat to 'keep up', the tank will get COLDER (after all, it's trying to absorb heat, just like your refrigerator). If it doesn't have sufficient internal surface, the pressure will drop radically, and you'll get insufficient gas vapor pressure, lean mixture, and burned valves. The components of a gaseous fuel propane system are similar to that of a liquid gasoline system, with just a few things different... The MIXER: Mixes gaseous fuel with air to make a combustible mixture. Imagine a tube, in the venturi of your carbeurator, but instead of vacuum drawing liquid from the carbeurator bowl, it's drawing gaseous propane... that's what's happening. IN a dual-fuel engine, there's a liquid jet, as well as a gaseous 'stub'. To make a dual-fuel engine, one could even drill a carbeurator and install a 'stub'. Just prior to this stub, is an adjustable orfice that limits maximum fuel flow... it's 'like' a main jet needle adjustment, but it has a different shape to suit the nature of gaseous, rather than liquid fuel. This adjustment is referred to as "LOAD VALVE". It pertains ONLY to full-throttle fuel limit, so don't mess with it unless the engine is at max governed speed and absolute full load. Zero Governor... aka Negative Pressure Regulator... aka DEMAND REGULATOR: This is a device which METERS FUEL based on ENGINE DEMAND. You've got a stub in the venturi of a carbeurator. As airflow THROUGH THE VENTURI increases, the pressure signal in that STUB falls (because it's a vacuum... remember... in a liquid system, it's sipping liquid gasoline from the bowl!) the Demand Regulator feeds a little fuel to the stub. It does it IN PROPORTION to the venturi stub's DEMAND... and here's how it does it: Your average regulator, like what's on your air compressor is simple: Full tank pressure of 138psi on one side, and the regulator LIMITS pressure to 90 for your power tools. Now grab that knob and crank it down to 10psi... you've got 138 on one side, and 10psi on the other. Keep cranking... down to 1psi... and you get 1psi out. Keep going. Go to NEGATIVE 1psi. It ain't gonna flow at all, right? Now put your mouth over that hose and suck on it... it's gonna flow. Why? Because you're pulling the outlet pressure BELOW -1psi. Now imagine that was propane, and the hose was stuck in the throat of the carb... you have DEMAND REGULATION at -1psi. This is exactly what a Demand Regulator does. This is exactly the same function that the carbeurator fuel bowl does: Venturi pressure SUCKS fuel up through the main jet based on demand. It ALSO accomplishes what the carb's FLOAT VALVE performs: It stops fuel flow based on demand. If the engine's not drawing fuel, it will not allow more in.... but wait... that's not all! The FLOAT VALVE maintains a specific FUEL LEVEL inside the bowl, and in doing so, it assures that it takes a certain amount of VACUUM to pull a specific amount of LIQUID through the main jet. IF the float level is really low, it will take more vacuum to pull a given amount of fuel, because it has to be lifted HIGHER. If the float level is too high... it will pull TOO MUCH fuel, or possibly even 'run over' and flood the engine. The Demand Regulator maintains this also... it's outlet FLOW sensitivity is adjustable (gain adjustment!) at it's 'fuel cutoff' point. It's gotta be really sensitive to pressure in order to work right. ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: DaveKamp
Date Posted: 24 Dec 2017 at 6:24pm
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Now, in order to be safe and perform well, the Demand Regulator MUST shut off reliably, and be sensitive to demand at low speed, as well as responsive to high demand. To make that work on a very SLIGHT vacuum signal from the mixer, the Demand Regulator's PROPANE GAS INPUT PRESSURE is very low. it's measured in INCHES of WATER COLUMN ( " W.C.). 11" W.C. is the general standard for both propane and natural gas. You may see some systems in Ounce-Inches, or a few other methods, but W.C. is the most common method, because anyone can MEASURE it with nothing more than a yardstick, piece of clear plastic hose and a cup of water. Make a manometer by straw-sucking about half a tube full of water in, and bend it into a U, tape it to the yardstick, and hook one end to your test port. When the DIFFERENCE of the high and low side comes out to 11" (5.5" down, and 5.5" up), you're at 11" of water column. ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: DaveKamp
Date Posted: 24 Dec 2017 at 6:28pm
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To feed the Demand Regulator, you need some source of gaseous fuel that's regulated to 11" w.c... this is referred to as a 'second stage' regulator. It takes some 'first stage' pressure (typically 2psi or 10psi) and knocks it down to 11" W.C.. Tank pressure is the FIRST STAGE. As you saw above, tank pressure can be anywhere from a couple pounds at -30F to 250psi at 125F. The first-stage reg will take that tank pressure and knock it down to some industry standard... usually either 2psi or 10psi. And this all assumes that you're working with VAPOR WITHDRAWL from the tank... that means... liquid in the tank is evaporating BEFORE leaving the tank. ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: DaveKamp
Date Posted: 24 Dec 2017 at 6:34pm
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Problem here, though, is that at extremely low temps, the engine very well may demand more vaporized gas than the tank can accomodate... because the tank is too darned cold, and there's not enough surface... so there's insufficient pressure to feed the reguators, flow through the lines, and feed the mixer reliably. So here's what they do: They pull LIQUID directly from the tank, and from there, it goes into a little gadget called a 'converter'... it's a housing that has liquid propane in one chamber, with a water-jacket around it, with hot engine coolant flowing through. it provides all the heat necessary to boil that liquid into vapor at what would otherwise be WAY TOO high a pressure, and way too low a temperature, to provide enough evaporated gas to burn. This is also often referred to as an 'evaporator'. It's easily distinguished because it has a pair of coolant lines going through it. On air-cooled engines, an evaporator can be physically bolted to the block in some warm spot to do the same job without liquid... just exhaust or engine heat passing through the housing. ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: DaveKamp
Date Posted: 24 Dec 2017 at 6:45pm
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Now, it's imperative that when there's no demand for fuel, that the propane supply (whether gaseous or liquid) is VERY POSITIVELY shut off. If not, it will leak out, causing fuel to be lost... or just causing you to get your shop blown up... both being relatively inconvenient. The device which accommodates this, is called a FUEL LOCKOFF. They're operated by typically one of two methods- either by an electric solenoid, or by a vacuum diaphragm on the intake manifold. If you see a gadget hooked to a line coming directly off the tank, with either a vacuum hose to the manifold, or wire to the ignition switch coming out, you found the lockoff. You might also find that there's a filter... it's to keep debris from getting into the fuel system, very SPECIFICALLY, to keep it from fouling the LOCKOFF. Propane doesn't 'get' dirty... usually it will get into a system only because someone has failed to clean out a coupling prior to changing a (removable) tank, or not cleaning the filler hose prior to filling a (permanently attached) tank... or finally, from someone not properly cleaning, or improperly applying sealant to plumbing connections during fuel system reassembly. Don't be surprised if your fuel lockoff has an integral FILTER. The Impco VFF series is a filter AND lockoff, all in one unit. when you take an evaporator, and add a couple of regulator stages... you have tank pressure in, with a MIXER at the other end... now you have all those things in one neat little package, and it's referred to as a "FUEL CONTROLLER". An IMPCO COBRA or IMPCO J fit this description... as does a BEAM T50 or T60. An example of just a ZERO GOVERNOR... is a Garretson KN. From what I understand, Allis used Ensign, as did many other manufacturers of the time. I don't know how common rebuild parts for Ensign components are nowdays, because I don't have a factory Allis LP system, but if you look at the factory stuff, you'll probably be able to determine what part is what, and what it's doing, very easily. ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: DaveKamp
Date Posted: 24 Dec 2017 at 7:26pm
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And i see links in my posts... I have no idea why... I didn't put any of them in, so please ignore them. ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: HD6GTOM
Date Posted: 24 Dec 2017 at 9:15pm
| Tom, I converted several tractors using impco kits. The kits for JD tractors came with regulators that were two small. We got an argument from them when we made it known to them. We were able to get the next size larger regulators and it solved the problem. They did start sending the proper regulator for the big JD's. Good luck with your conversion. You should get the proper tank. I never did a D17. |