Jump to content

Chasdev

Advice on dual fuel portable generators?

Recommended Posts

Thinking on picking one up and have been reading about a zillion reviews and ratings but I would rather hear from guys that already own/use one..

Planning on using propane 99.999% of the time.

I'm looking in the 5000 watt range, perhaps as low as 4000.

 

Share this post


Link to post
Share on other sites

Never had a dual fuel one but we had a 10kw propane generator on the food trailer and it was a major PITA to deal with. We used 35 lb bottles for it because my idiot business partner wouldn’t listen to me about hooking it up to one of the two 100 pound cylinders we had on the trailer. Do some research and see what the requirements are on bottle size for the size genny you plan on buying and do not deviate. The gas is in liquid form in the bottle, it has to vaporize before in order run. If the tank is too small, the gas will remain a liquid and freeze up your carb, you’ll also have a significant pressure drop and the gas won’t flow from the tank. I don’t know the exact science behind it but I know it sucks when you’re needing power and having to work on the generator when it should be running. Save yourself the headache and just get a gasoline generator unless you are permanently installing it and have the appropriate size tank to go with it. If I ever have another food trailer, it will have an Onan Diesel onboard. 

Share this post


Link to post
Share on other sites

I'm a retired auto tech so I can deal with all carb issues plus it's so hot in Austin that anything freezing up in the summer would be a flat out miracle!

Tank size is not an issue because it's going into in my storage shed and I'm hoping any power outages don't last more than one day, fingers crossed.

My plan was to go with multiple small tanks, unless the cost for many is way more than the cost of one or two larger units.

The buy in prevents me from going up to 10k watts, something in the 4000/5000 watt range is my top dollar.

Share this post


Link to post
Share on other sites

Multiple small tanks will give you issues, a single 100 pounder should be ok for a fixed install. Propane is -45°F so even hot outside ambient temps won’t keep the bottle from freezing when the pressure drops, we were dealing with this issue in 90°+F summer heat. Like I said, it’s all about tank size, the smaller tanks can’t flow fast enough to vaporize the propane. The only way to combat this with smaller tanks is to run a bottle heater, similar to a nitrous setup on a car. 

Share this post


Link to post
Share on other sites

Something "haywire" here.  Not familiar with the science of running propane, but they have been using small propane tanks to run forklifts for decades.  There must be a poor design issue if there are problems, either with the generator/carb or the tank designs. Maybe one could blame the dual-fuel design, but that has been very successfully done in some applications as well.  I would do more research on this whole dual-fuel idea.

Share this post


Link to post
Share on other sites

The problem is with the fuel in the carb evaporating and leaving a gummy varnish that effectively sticks the float and clogs the pilot jets which prevents starting or smooth running.

The cure is two fold, add a fuel stabilizer to the storage can and also shut off the fuel valve and run it out of gas which causes the carb to run dry so that the amount of fuel left in the jets and fuel passages can't block them when it drys.

Dual use is mainly run on propane and switched to gasoline for the swap out of a new tank of propane or while the replacement tank is sourced.

Share this post


Link to post
Share on other sites
10 hours ago, bcrgrill said:

Something "haywire" here.  Not familiar with the science of running propane, but they have been using small propane tanks to run forklifts for decades.  There must be a poor design issue if there are problems, either with the generator/carb or the tank designs. Maybe one could blame the dual-fuel design, but that has been very successfully done in some applications as well.  I would do more research on this whole dual-fuel idea.

 

Forklift propane tanks are specially designed for the application, they use valves that flow the proper amount of fuel without freezing. A gas grill tank or other similarly sized tank will not. 

Share this post


Link to post
Share on other sites

I know nothing about the propane aspect but the gasohol is terrible for small engines. I used to just run all the gas out of the grounds care equipment and store for the winter. One year I had to rebuild all of the carburetors. Now I automatically treat all fuel when I buy it. Knock non wood so far so good. When I researched  this apparently gas can spoil  very quickly if it gets hot. I do know that many remote site campers have converted their Honda generators to propane because of problems with gas Quality.  Grounds care people pay as much as $45 for ethanol free gas to store their equipment for the winter.

Share this post


Link to post
Share on other sites

I used to service/overhaul carburetors for a living and I promise that if you use Sta-Bil fuel treatment and drain the fuel before long term storage, your engine/s will start up just fine next time you need them.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...