Propane Broncos - Who is running one? Why not?

[rguest3]

I recently purchased a 1971, F100 4WD Short Bed. I have always wanted a short bed 4wd in this generation F100 and I finally found one.

Here is the interesting part. It has a FE 360 that runs on Propane. I have not done too much investigating yet, but I'll figure out which system it has. It does look like the Holley System that Gotpropane.com sells. It runs very well, the oil is as clean as can be and it acts like it's an EFI system.

So why would I not want to install a Propane system on a Bronco? Seems to have a lot of advantages over a carb, and not just being cleaner.

Recommendations and experience with the Propane systems is appreciated.

Thanks

 

[jckkys]

Seems like a good idea for short trips. There isn't much room in an EB for a big tank, that would be needed for long trips. CNG systems have the same problem. Rock crawlers could use it. No problems with steep angles.

 

[SteveL]

Guys have done it. I think they mounted the bottle in the rear of the bed. Off road it works great as long as you have enough fuel. Out here many commuter Van's were using it. A friend bought a used one. He liked it except having to go up near lax to refuel.

 

[Bronco4x4]

There is a recent post showing vintage baja 1000 EB’s that ran on propane.

 

[Pa PITT]

... I've got a lot of history with Propane.
You bought that old truck with Propane on it ... Leave it on it ..
.. But at this moment in time I'm buying GASOLINE FOR ABOUT 25c. cheaper than I can buy Propane. SO GAS IS SO Much easier to work with than Propane.
So back when I USED ALOT OF PROPANE .. One Case 830 tractor I still have . & Irrigation pump for water . I wasn't giving but about 30c Per gallon & Gasoline was about 75c.. & MY Irrigation pump set there with a 500gal tank .. I like propane but I don't want it on my Bronco.
...........
.... Now I think there is a law saying you need to house the Propane Bottle in the open bed of your truck. Mong time I could be wrong . So the Bottle in the rear of your station wagon Bronco is unsafe.
... & Normally if your on a trip there is one place in a town to buy fuel. A buddy & I WERE in Mississippi at about 11pm night .. The guy was pissed because we needed 100 gallons of fuel. So He came down for a 20.00 tip & filled us up.

 

[rguest3]

One of the closest gas stations to me also refills propane.

I rarely drive my Broncos a long distance so a smaller 10 gallon tank should work.

Propane does not separate and go bad over time as gasoline does, if not driven often.

I see the Propane as being a much cleaner system than using a carb.

I'm kinda convincing myself to try this on a Bronco build. I really don't see a down side to it, for me anyway. I'll put some more miles on the F100 and see if I really like it.

 

[sykanr0ng]

There was a company that worked with the company I worked for that had a propane powered truck that reeked of the propane, the guys said no matter what they did to try to fix it it still smelled that bad.

 

[SteveL]

I think getting it under the hood was an issue. There were a few guys chiming in that had it. Dont know if they're still here.

 

[rguest3]

That is one question that I have been thinking about. How much taller is the Propane carb than a standard gasoline carb?

Additional investigating needed. I'll measure the one on the F100.

 

[Timmy390]

4 barrel kit
http://www.gotpropane.com/p565.html

They make a kit for my Samurai and I'm considering it.

Tim

 

[blubuckaroo]

lots of clubs using propane over 8500' in the Sierra. It should work great on a Bronco too.

 

[bbaltered]

Propane runs good and runs cleaner than gas. I think it also has a higher octane rating. But, it has less BTUs per gallon than gas so your MPG will be a little bit less.

 

[rguest3]

Yep, Gotpropane has a lot of great info. The 4B system looks like the one that is on my F100. It mounts on a standard Square Bore 4B intake and handles about 320 HP. There is a higher HP version as well.

Very interesting that Altitude has No effect on the Propane system. No need to retune. It can also be run at any angle which is great for off reading. Very popular route for Rock Crawlers.

 

[SteveL]

There is part of the motor that has to be up to running propane. I think it was in the heads, valves maybe. Something about higher octane or heat.

 

[Skinnyr1]

Buying propane is more expensive than gasoline. If I recall correctly, gas has a higher Btu per gallon than propane too, making propane less efficient from a dollar stand point. The propane may run cleaner, but you are going to be using more of it and it costs more per gallon unless you are buying it by the 1000 gallon tank.

Lots of info on this when you compare generators, as it is common to see home generators run on propane. They are much more maintenance friendly, and require less up keep, but when using propane, they are thirsty and more expensive to use.

 

[Slednut10]

One of the closest gas stations to me also refills propane.

I rarely drive my Broncos a long distance so a smaller 10 gallon tank should work.

Propane does not separate and go bad over time as gasoline does, if not driven often.

I see the Propane as being a much cleaner system than using a carb.

I'm kinda convincing myself to try this on a Bronco build. I really don't see a down side to it, for me anyway. I'll put some more miles on the F100 and see if I really like it.

Since the BTU content of a gallon propane is roughly 3/4 the BTU content of a gallon of gas, that 10 gallon tank (filled to a max of 80 percent) is about the equivalent of a 6 gallon gas tank. You definitely won't go far on that

 

[rguest3]

I agree, the 10 gallon would be too small. I was looking into tank sizes last night. 21-30 gal are readily available. I'll have to weigh all the issues and options until I decide to go this route or not.

I'll use the F100 as a test mule to see if this is a good option, or, a pain in the ass.

 

[Slednut10]

Just for size comparison, the common 20 lb tank holds 4.7 gallons of propane. Any idea on the tank size in the F 100?

 

[rguest3]

The F100 has a fairly large tank. Almost the width of the bed inside. I would guess at least a 24" diameter. Just a hair higher than the bed rails. 200-250 gallon???

 

[ntsqd]

That propane is a 'dry' fuel has been mentioned. Needs hard valve seats. Some have mentioned higher octane, which is true. What hasn't been mentioned is that to get the most out of that fuel the engine really needs to be built with that fuel in mind. Engines built for gasoline and then converted tend to be a bit of a slug. Particularly smog era engines that already suffer from low CR's.

Some other numbers worth keeping in mind:
Propane BTUs/gal: 82.4k; Gasoline BTUs/gal: 109k-119k
Propane Stoichiometric AFR: 15.7; Gasoline Stoichiometric AFR: 14.7
Propane Octane (Research/Motor): 112/97; Gasoline Octane (Research/Motor): 88-100/80-90

One of the best known EB's in Canada has always been propane fueled.