Removing unneeded LP gas plumbing to hook up NG hose.Posting pics need advice please

Just got my hands on my used genny,and need to find out what LP plumbing i can remove(all 3/4") And where to install my 2"hose connector. I am posting some pics in the hopes that the pics are good enough where as anyone can advise me.I can take more pics if needed. Thanks Dan

Hey DannyC
Real nice unit. The single phase/three phase and mutiple voltage possibilities means the gen head is a very good four pole convertible 12 lead style.
This engine was available as natural gas fueled also. Look at pictures here of a later distri butorless version for the Ford Industrial natural gas power specs:
On both od these engines set up for propane there will be an uneeded water/en gine coolant heated liquid LP to propane vaporizer. The pictured inline gas pressure regulators will be wrong for street supplied methane/natural gas. Proper natural refulator will have 3-4X the size of diaphram. And the domed cover gas mixer above the throttle body will have the wrong smaller gas flow orifice holes in it for the much denser prpane gas versus natural gas. This mixer should be marked as either “Century” or IMPCO and they could supply the proper guts for natural gas. The electric inline fuel gas locks should be retained and reusable. Either Century or Impco could set you up with an installation flow diagram, piping sizing and the proper natural gas regulator. Bet Onan them selves would probably have this information too.

Steve Unruh

Hey Steve; Thanks for responding. I gurss i have to convert to nat. gas to run my gasser? Or, can i just attach my 2" gasser hose to the top of the mixer bowl And meter the air intake coming out of the original air filter housing? Do i have to keep all of the old plumbing before the mixing bowl? I’m not going to run on nat. gas but i guess thats close to wood gas. Thanks much, Dan

Ah Ha. I see now. No DannyC. woodgas fuel energy density is even farther different from natural gas (methane) than methane is from propane.
The woodgas is very bulky in comparison to both and is diluted with 50-60% nitrogen and water vapor and needs to be metered into the engine in a +/-20% from a 1 to 1 ratio with the sucked in engine air. There is NO POSIBBILTY to make the fuel gas orifices in one of these purpose built propane or methane mixers that large to be able to pass enough woodgas. Been tried - I do not know of any sucessful. These are pot metal castings and would quickly corode out to destruction from the acidic/wet woodgas anyhow. Seen that already.

For woodgasing on your set up you would have to extend up the propane mixer and introduce a woodgas stream below this into the throttle body separately.
Sounds simple. It IS NOT. You then have to have 100% tight sealing air and fuel gas valves to the propane/methane mixer added on which really complicates things.
Propane and natural gas (methane) are pre-purified/refined taking out 99% of the water and and other non-fuel componetes. They are delivered to the mixer under PRESSURE and the mixer just senses air flow and valves in these pre-pressureized fuel gases in the proper ratios to the air and mixed them into the air stream.
A gasifer has to be engine sucked HARD to get fuel gas flow through the flow restictions of the reactor char bed; the cyclone/settlement chamber; the cooler/condenser and then filter. In real useage you have to contol/restrict the engine air to create enough engine manifold vacumn to pull IN woodgas fuel delivery to the engine.
This is a primary reason why diesels are so hard to control when woodgas dual fueled. They normally operate with NO intake manifold vacumn. Easy to meter in pre-pressurized fuel gases like NG and propane. Woodgas you have to trottle restrict the intake then to created a manifold suction to pull in the woodgas fuel.
Why gasoline carbureted engines; YES, because they DO suck the liquid fuel also CAN be made to duel fuel gasoline and woodgas. PITA with havin to set up many dual system fuel and air controls though.
WHY port fuel injected based gasoline engine are by far the easiest to dual gasoline and woodgas fuel - to the port delivered FI is NOT intake manifold vacumn dependent.

If you want to actually woodgas fuel this best to set it up for the single fuel of woodgas period. You can for starting up and unloaded “idling” perposed only hand valve in some bottled propane flow. I have done this on gen sets.

Steve Unruh

Forgive me for not being clear, my intentions all along were to convert to only wood gas.Can everything above the throttle body be removed(and saved to put back if needed) and my valves and hose be attached there.There are wires attached to some of the plumbing that i wish to remove and don’t know if disconnecting them will screw something else up.I selected this setup because of our discussion once before where you told me about these setups being ideal for woodgas because they are already setup for gasious fuels(timing,compression and so on)I just wan’t this to go as smootly as possible as i have a way of over coplicating some things i work on. Your expertise is greatly appreciated. Dan

Ha! No; forgive me DannyC for the delay in responding. Two different “Must GO” Chrismas parties to help set up for and post clean up. Then a now sick wife ran down by said parties. Then a wild wind/rain storm temp power outage overnight event. Why we insist on wood heat here.

On your current set up very obvious the propane converter used a gasoline lower as the throttle body and rubber hose clamped a patent brand propane mixer onto the top of this.
OK. Easiest way to woodgas this would also be keep the speed govenor connected lower ex-gasoline trottle body to control the mixed ratio woodgas/engine air supply to the engine. Then rubber hose connect to the top of this ( just like the current propane mixer is) what I like to call a WayneKeith woodgas mixer solution.
Go to a U-Pull-it wrecking yard (or; yours, or the nieghbors scrap pile/back yard) and get an all metal clam shell type are cleaner housing assembly. You can adapt mount this to a metal pipe flange with stub pipe protuding for the rubber hose to clamp to. Following the Wayne Keith underhood pictures: put a side port in for the woodgas and use the stock air snorkle adaped over for the engine air. BOTH of these will have to have added in cable operated flow contol valves. Wayne makes his own. Others use take off machined cast metal trottle bodies adapted over. Chrysler mini van wrecking yard trottle bodies are cheap and available for this. DO Get as much of the trottle cable or cruise contol cable for these as you can while you are at it. Do paint all of your work on the inside to prevent woodgas corrosion from shedding off hard iron corrosion particles down into the engine.
This will work for manual mixing ratio contol to get you up and going. Then you learn what you need to do for woodgas and air flows for starting up, running low loads, heavy loads and load shed offs “overshoots”.
Improve later as you desire. Automate the mixing contols - different ways; mechanical, flow vam=cumn sensed and electronic feedback.
Later eliminate the gasoline carb body with it’s built in venturi flow restriction in favor of a take off wrecking yard Fuel Injection trottle body for more gases flow and power potential.

AC gen set the real challenge is to compensate for sudden heavy elecrical user load turn offs events. On a vehicle this would be like at full power, RPM and speed someone stabbing in and holding down the clutch without taking thier foot off of the throttle. OUTCH!! Gen-set the Govenor will try and reduce the engine speed but the gasees flow mixtures will want to keep going pushing into the engine. You will either lean out and back backfire, or grossly over rich causing the engine to stall and die. Expernece will show you what you have to develope around for your system and your useage of it. Only you can do this part.

If you want for easier starting up and warm up idlling to use propane fuel, just hose barb in a propane flex line from a small bottle into the side of the aircleaner mixer housing. DO only control this from the bottle port valve and be sure the bottle valve still does have a back flow preventer for safety.

Your wires to your current propane fuel assembly that I see pictured are for a manditory electical flow gas shut off shut off valve. These are supposed to be set up to de-enrgize and stop gas flow when the engine is stopped for safety. For engine starting they either have a manual push button electric switch bypass or are wired into the engine starter cranking circut.

Steve Unruh

Thanks Steve, I think i get most of what you are saying.Not sure about the control cables being its a genset and can reach all by hand.Guess first step is to hook up and go from there(sure of more questions to come).
Till then; Dan

Hey Dan
The engine suction and air/gasses flows will want to suck open and close the trottling valves. Any looseness and they will even flutter with intake pulsations. So you will have to set up sone kind of fricton or detent positioner anyhow. With spring pull closing and a standard friction drag button headed panel mounted control cable you can finatly control the flow valve openings all conviently away from the heat and viberation at a control panel.
Steve Unruh

Hi Danny, I have a 7Kw Kolher gen set from a motor home that ran on gasoline and have fixed it to run on charcoal gas. The only adaptation I made to the carb was to remove the air intake and put a 1" steel “T” fitting over it. On one side of the “T” is the hose that brings the charcoal gas in while the other side has a gate valve to control the amount of oxygen comming in. The throttle valve is left in place along with the linkage that attaches to the govenor to keep it humming at 1800 RPM. I have over seven hours of run time and have not had any problem with the throttle fluctuating back and forth with changes in load. It takes about 5 minutes from a cold start to get the engine running and the air valve set. Once set though, I rarely touch it until the unit needs shut down. This should also work on your LP fueled genset. The ideal is a throttle body with wide openings for woodgas, but the present setup will work also
The photo shows how it is attached to the carb. The linkage from the govenor to the throttle is also visible.
Gary in PA

Thanks for putting this up GaryG.
Very relevent here and on Wayne Bakers “Kohler 10 kW” thread:

Love those pictures and real in use feedback encouragement.

I find that woodgas mixers fall into three broad catagories:

  1. Simple, small internal volumn “T”, “Wye” pipe and tube mixers
  2. Relatively simple medium area internal volumn (usually round), open, hollow, close coupled mixing chambers as I tried to describe with my “WayneKieth” air cleaner housing mixer suggestion.
  3. Complex, different venturi/cyclone effect, swirly, reversal flow types with a sharp edge sonic mixing area.

Good news is they all seem to work. Some, however better on different engine types, with different gasifier systems, in differnet engine system useage. Fella just has to keep an open mind, try and see, quit searching for idealism once satisfied with the real working results.

Gate valves do work too. Even easy to automate with a gear or chain drive electric stepper motor.
1/4 turn ball valves work well manually but are very tough (but still possible) to automate unless a very expensive commercial type already designed to be remote contolled. (Hint: a large sector gear type window lift motor assembly would work on these.)

Steve Unruh

Hi Steve; when I get to the genny, i’ll remove all from throttle body up and carefully stow away for future use. I will also make sure the throttle plate is not loose and will try a spring close setup and go from there.You said to paint everything inside to keep metal particles from engine.What do you paint it with? Dan

Hi Gary; Big fan of your charcoal gassers and will try one at some point. Thanks for you info,I think i will make a mixer bowl to which a tee will attache.I will have a suction fan at the air intake to pull the gasses thru pipeing to genset.It will have metering valve on it.Will see if it works and go from there.will keep site posted and surely will have more questions. Dan

Hi Danny, Let me toss out my thoughs on how you plan to put woodgas into your generator. Before doing so, I want you and anyone else reading this to understand I am thinking “out loud” and am not trying to discourage you from your intended plans. The view point that I’ll share is comming from the stand point of simplicity and will let it go at that. What you end up with may be vastly better than what I propose and needs tested.
Here it goes. Mixing bowl, suction fan, metering valve. Mixing bowl will work, but do you need such a large area to mix the wood gas and air in? Suction fan is necessary to get the generator started but once that happens, the engine seems( to me) to do a good job sucking the wood gas in. Metering valve. Never messed with one of these but orifice size will depend on the pressure created by the fan and then adjusted to the speed of the engine. Just seems more complicated than it may be worth, but… you also may be on to something. Please keep us updated on your progress.
We are expecting the snow on Friday. Don’t let it all drop over your place because I’d like to get some here too. Calling for only 3", but that is OK, at least it is better that the warm weather we have been having lately.
Have fun and until later,
Gary from PA

Hi Gary G.; No snow here in central Florida, but it sure would seem more like the Christmas times i remember from Michigan.My mixing bowl would be small and round,I just think the swirling together of the gasses will blend them together to burn a little smoother.The fan will do double duty, will.pull gas to the engine and then electric current will be shut off.Then the metering valve will be attached to the fan to use like your gate valve to control the intake air.Both the gas and air mixing valves will be 2" like the hose.So in other words,fan will pull gas to the engine and after shutting it off it will be the air intake opening.Both valves are ball valves. Will keep all informed of progress or setbacks. Merry Christmas to you and yours. Dan

Gary H. Replied but sent it as a new comment.Just so you get notified.Rookie mistake,Sorry. Dan