external fuel supply for Honda-engined genny

[working on it]

I just re-worked my generator slide/swivel mount, and also attempting to build a sound-reducing enclosure for it (it's not a Honda EU "quiet" genny, but a Honda/Craftsman hybrid). I designed the trailer to be able to run the generator to supply power to the A/C, but it only has a small fuel tank, inadequate for more than a couple of hours runtime. I never did get around to making/buying a larger supply tank, so it could run all night if need be. The Honda EUs have special systems made for that, but not my generator. It does have a pulse-driven fuel pump,

circled part is the pump

honda small engine fuel system.gif (18.59 KiB) Viewed 7093 times

and the literature on the engine says it can draw/feed fuel up to 19 inches away from the tank, either above or below carb level (of course, I can no longer find the literature). I'm considering adding a feed line (on a tee), with a shut-off valve inline, and another return line to prevent oversupply, and simply dropping the end of the line(s) into my 5 gallon gas can, and run the genny that way. I read that the pulse pump will not overcome the needle/seat setting, but just in case, the return line seems needed. Either with or without a priming bulb?

line to the second carb will be a return line

SimFuelSys_1.gif (23.62 KiB) Viewed 7093 times

Or should I just add a marine tank, with all the equipment, even a fuel gauge? I really don't know if the pulse pump will actually pull from 12" away, and at a 6" elevation (projected placement on a stand next to it, both inside a soundproofing/cooling box), but I'm not familiar with outboard fuel systems either...it may overfeed the carb anyway. Any thoughts or experience doing this? I'll experiment if not (of course, outdoors, with a fire extinguisher in hand). I've run V-8 engines via a similar method (putting cars on a trailer, in the wild), but on a very short-time basis. I want to be able to run this one while I sleep, unattended, safely.

[Dale M.]

Ever thought about dual fuel conversion.... There is company out there somewhere that makes conversion units so you can switch between propane and gas....

https://www.google.com/search?q=dual+fu ... e&ie=UTF-8

Other thoughts on this is, if engine is equipped with pulse driven pump it will probably not over pressure carb as both units are designed to work together...So need for return line is probably not necessary...

The idea of a fuel can sitting there with lid/cap off and a return line just dropped into makes me have a vision of some night critter (raccoon or dog or cat) bumping into it and it falling over and fuel running out onto ground and then a huge vapor cloud capable of causing instantaneous ignition( EXPLOSION)...

If you want external tank get something designed to be used as a fuel tank (marine?)... Idea of squeeze bulb (prime) and a selector valve does have it merits....

Dale

[rowerwet]

I added a tank like this to my parents generator since it had such a tiny tank http://www.ebay.com/itm/4-5-GALLON-GENE ... 43c830d428

[working on it]

Ever thought about dual fuel conversion.... There is company out there somewhere that makes conversion units so you can switch between propane and gas....

https://www.google.com/search?q=dual+fu ... e&ie=UTF-8

Other thoughts on this is, if engine is equipped with pulse driven pump it will probably not over pressure carb as both units are designed to work together...So need for return line is probably not necessary...

The idea of a fuel can sitting there with lid/cap off and a return line just dropped into makes me have a vision of some night critter (raccoon or dog or cat) bumping into it and it falling over and fuel running out onto ground and then a huge vapor cloud capable of causing instantaneous ignition( EXPLOSION)...

If you want external tank get something designed to be used as a fuel tank (marine?)... Idea of squeeze bulb (prime) and a selector valve does have it merits....

Dale

This is an older Honda GC engine, with who knows how many hours of run-time on it (was used to charge batteries, for many years between rounds, at drag races), so I was using it as a testbed for on-board use, maybe going bigger with the next one if successful. I don't think converting it to propane would be cost-effective, if it died of old age. Besides, I steered the trailer away from propane use anyway...both my Colemans (Northstar lantern, and stove) are dual-fuel, so I could carry gasoline for many uses-tow vehicle, lantern light, cooking my Spam- if needed. I think you are right about the hazards of an open container of fuel, and also that the pump-carburetor system on my engine has no return line, so it probably won't need one. The priming bulb would only be needed if the tank was below the pump level, and if the tank was higher than the pump,with a selector valve inline, then flow could be shut-off to prevent filling the inactive pump when not in use (gravity seepage). Perhaps the tank shown by rowerwet could be mounted above the generator (in the space now occupied by the Coleman Corner grouping-C.fuel, C.lantern, C.stove).

Coleman Corner (old photo)

Photo225m7.JPG (155.85 KiB) Viewed 7045 times

[Socal Tom]

I've done the marine tank thing with intermittent success. The 19 inches is based on pure hose, filters, bulbs valves, fittings etc, add additional restrictions that reduce the number of inches you can work with. You are best off if you can put the external tank higher than the generator, then you might get a siphon working.
Tom

[MtnDon]

I'm not sure I would want to get a siphon going. At least a pulse pump is going to stop if the engine is stopped. A siphon would require a separate action to close a valve to guarantee no flow, wouldn't it? Maybe I'm missing some key part of the thinking on that? I might have trouble depending on memory to close a valve faithfully. Would it be possible to retro fit a larger tank in place of the stock tank?

[rowerwet]

I use the valve on the tank as my generator shut-off, run it out of gas to stop, never have a problem starting

[Dale M.]

Carburetor should have needle and seat or diaphragm to control fuel flow so fuel pump does not over feed engine.... Should prevent any flow from gravity or siphon feed.... Several of my B&S engines and a lot of other engine applications I have observed with fuel tanks higher than carb are float type, simple inspection of carb will tell....

Dale

[MtnDon]

Yes carbs have floats and needles valves. And I have personally seen them fail with the result of flooding the engine with fuel. That is one good feature of the way the Honda EU's are setup using one control for ignition and fuel cut off.

[working on it]

Yes, the carburetor has a needle/seat/float set-up, I know...after sitting for a couple of years, unused (without storage prep), it wouldn't start, so it was disassembled for cleaning (used Sta-bil after that), and I handled those parts. The question now revolves around the choice of using the marine tank/pressurized/siphoning tank (if I need to place the tank beside or beneath the engine level, or the gravity-feed tank (if I need to locate it above the engine level). If I do get the gravity-feed tank, and install it in the Coleman Corner spot, with the shut-off valves below (I'll put one just at the tank, another at the filter-to-pump level (bracket-mounted in the same location where the original tank>to be removed< is now); that way, I can guarantee that the flow can be shut off, in case of line breakage or if either valve fails to work, or to terminate flow quickly at the pump, upon engine shut-down, like this:

I use the valve on the tank as my generator shut-off, run it out of gas to stop, never have a problem starting

A crude drawing of my plan:

overlaid drawing/genny out of position/generalization

Photo225m7.JPG (117.65 KiB) Viewed 7005 times

Partial opening of either or both valves can regulate fuel flow, so as to not overcome the carb (I can use a see-thru filter to visually determine the flow; I don't think a pressure gauge would work here). I'll examine my generator today, measuring exactly what I have to work with, and see if the aforementioned tank will fit (possibly on another slide-out). I'm leaning heavily towards this gravity-feed tank installation, as I have had some trouble (40 years back) with the outboard-marine fuel systems (on more than one boat). I'll see if I can take better pictures, to illustrate.

[Socal Tom]

I'm not sure I would want to get a siphon going. At least a pulse pump is going to stop if the engine is stopped. A siphon would require a separate action to close a valve to guarantee no flow, wouldn't it? Maybe I'm missing some key part of the thinking on that? I might have trouble depending on memory to close a valve faithfully. Would it be possible to retro fit a larger tank in place of the stock tank?

A siphon to a carb float valve or to something like the pulse pump would stop the same way as a gravity drain ( that's all it really is).
Tom

[working on it]

Took a coupla pictures of the pulse-driven pump,

pulse pump.jpg (86.28 KiB) Viewed 6978 times

pulse pump description.jpg (64.87 KiB) Viewed 6978 times

and measured spaces for the add-on supply tank, and distances for the fuel to flow. I also located the model # of my generator (covered up by my welding equipment, now using its converted cart) Sears Craftsman 580.327.750. From that info, I was able to find another manual on-line, and from that I got the specs on the Honda GC160 5hp engine. Following that lead, I researched fuel consumption data and flow recommendations: it consumes 1.2liters/hr (.32 gallons/hr, requiring a tank size of 3 gallons for a full nights sleep!) and will function with the fuel up to 500mm (19.685 inches) away from the pump. I vaguely remembered that last factoid, from my misplaced manual and research file from 2011. Well anyway, the distances will work fine, with a gravity-feed tank either placed on the shelf where the Coleman stuff is now (a tight fit, with the Northstar Lantern having to move elsewhere), or on the bottom next to the generator (don't really want it there, in front of my "shielded" electrical connection strips and shorepower tie-in). I had originally carried my 5 gallon spare fuel can there, as in the old photo, but replaced it with a cooler. Seems that the new tank has to go on the shelf, and I can make a platform over it, to stow the Coleman fuel and stove above the tank, and still be able to re-fuel. A slide-out will be needed to enable re-fueling outside the galley/storage; IMHO a safer option, with no spills inside the trailer. I looked at many other tanks, hoping to find a smaller footprint, but none appeared. I did consider a 3 or 4 gallon vertical drag-race fuel cell, to be mounted to the sidewall, but they're expensive. I also considered taking the behind-the-seat tank off my Dixon mower, but my wife wants me to repair it (again...she likes to ride it over stumps, garden hoses, large decorative rocks, tools, etc...).

[working on it]

Took a coupla pictures of the pulse-driven pump,

The attachment pulse pump.jpg is no longer available

The attachment pulse pump description.jpg is no longer available

and measured spaces for the add-on supply tank, and distances for the fuel to flow. I also located the model # of my generator (covered up by my welding equipment, now using its converted cart) Sears Craftsman 580.327.750. From that info, I was able to find another manual on-line, and from that I got the specs on the Honda GC160 5hp engine. Following that lead, I researched fuel consumption data and flow recommendations: it consumes 1.2liters/hr (.32 gallons/hr, requiring a tank size of 3 gallons for a full nights sleep!) and will function with the fuel up to 500mm (19.685 inches) away from the pump. I vaguely remembered that last factoid, from my misplaced manual and research file from 2011. Well anyway, the distances will work fine, with a gravity-feed tank either placed on the shelf where the Coleman stuff is now (a tight fit, with the Northstar Lantern having to move elsewhere), or on the bottom next to the generator (don't really want it there, in front of my "shielded" electrical connection strips and shorepower tie-in). I had originally carried my 5 gallon spare fuel can there, as in the old photo, but replaced it with a cooler. Seems that the new tank has to go on the shelf, and I can make a platform over it, to stow the Coleman fuel and stove above the tank, and still be able to re-fuel. A slide-out will be needed to enable re-fueling outside the galley/storage; IMHO a safer option, with no spills inside the trailer. I looked at many other tanks, hoping to find a smaller footprint, but none appeared. I did consider a 3 or 4 gallon vertical drag-race fuel cell, to be mounted to the sidewall, but they're expensive. I also considered taking the behind-the-seat tank off my Dixon mower, but my wife wants me to repair it (again...she likes to ride it over stumps, garden hoses, large decorative rocks, tools, etc...).

Rearranged the storage area, after I purchased an aluminum tank I found on E-bay (after remembering old-school racing, hotrodder tanks...). I bought a 3.5 gallon tank, 8x16 cylindrical aluminum, with mounting brackets, cap and fittings.

Old-school type tank

8x16.jpg (6.76 KiB) Viewed 6943 times

I cleared away the Coleman Corner, rearranged the items, and made enough space for the tank to fit on a slide-out bracket (so I can fill it away from the trailer-no spills-, and also run the generator pulled out and away from the trailer with the tank above it (both inside a sound enclosure, as planned for later).

• new arrangement
• Coleman Corner Condensed
• at least 16.5" width
• at least 10" depth
• at least 14" height available

I'll probably use the same Blum undermount sliders that I used for the generator, since 3.5 gallons of gas weighs 6.25lbs/gallon=22 lbs, and the weight of the tank and mounts will be another 10-12lbs. I sure don't want another failed slide-out moment, so I'll buy the best.

[Socal Tom]

Just a side note here. I don't see a fire extinguisher in any of your pictures. Given the fact you will have heat and fuel in the same space, it would probably be a good idea. You may also want to consider what your response should be in the event of a fire. It might have you add an extra shutoff valve or reconsider how you are packing things. ( I do risk analysis as part of my job, so I can't help but think about this kind of stuff)
Tom

[working on it]

Just a side note here. I don't see a fire extinguisher in any of your pictures. Given the fact you will have heat and fuel in the same space, it would probably be a good idea. You may also want to consider what your response should be in the event of a fire. It might have you add an extra shutoff valve or reconsider how you are packing things. ( I do risk analysis as part of my job, so I can't help but think about this kind of stuff)
Tom

I am going to have two shut-off valves (one at the tank outlet, one just prior to the pulse pump) plus the whole fuel-line from the extended-run tank will be detachable via quick disconnects. I may even make the aluminum tank detachable from its' slide, and completely remove it from the galley area, if feasible. The line will be teed off of the generator's existing fuel tank, so I can run the genny w/o the extra tank if needed. I have a fire extinguisher in each of my vehicles, and one in my wife's travel trailer. I didn't forget the little trailer, though...as soon as I added the electrical system, I mounted an extinguisher just inside the curbside cabin door. I was pondering adding one in the generator bay...now would be a good time to get another. I mounted the generator on a slide-out to remove the heat from the storage area; now with the new/improved slide pulling the exhaust further away from the sidewall (over a foot), which is better than the 4" before, I don't see a heat menace. I'll wait until all is cool before stowing it back in the galley. Thanks for your concern; I want it to work safely, and tow safely, despite my trying to cram items onboard (that are best left outboard) an occupied trailer.