Factory Propane Conversion Setup

[Propane350]

So, a million or so years ago it seems, I had my first project truck. A 1972 Chevy C20 Longbed. I purchased it for a few hundred dollars off Craigslist, but to my surprise when I went to check it out, it was running completely on propane. I'm a sucker for one-offs and novelty items so I snapped it up quick and drove it around for a few years without changing a thing.

One day I decided to take off the stupid aftermarket glovebox door that was on it and put back on the stock one that came along in a box of misc parts with the truck. When I flipped it over I saw that it actually listed the propane tank, heater and carb on the inside of the door, along with the HD shocks, clutch and rear end. The VIN matched as well.

I had never heard of Chevy putting alternative fuels on their vehicles until recently with the flex fuel and bio diesel and all that. When I replaced the engine and switched it back over to gasoline, I kept the whole setup, short of the tank.

Anybody know anything about it? Worth anything? Did it -actually- come from Chevy like that?

I've been very tempted to pick up a total beater truck just to throw it on. I was getting nearly 18 miles a gallon on a 350 when I first had it set up. And some places give highway discounts for using propane. At the time I was only being charged about $1.16/gallon. You loose a bit of the get up and go, but more then make up for it in the wallet.

[Moline_Puller]

Hey,

Yeah, LP was an option from the factory. There have been other trucks on here that were listed with factory LP.

LP engines run super clean and the engines love it. There is very little carbon in LP, so you don't have to change your oil as often, either. It is popular with rock crawlers, because the engines will just about run upside down, as long as you have the oiling as well.

I run an LP setup on my pulling tractor and I love it!



Chris

[Propane350]

Yah I loved it when I had it in my 72. If I didn't have a performance engine in my 68 I would drop it on.

[SS Tim]

If there is more than the propane prep option on the SPID I would really like to see it. Actually I'd like to see the SPID either way!

The factory offered LPG converted engines and we had a thread running last year if you want try searching for it.
But the public RPO L56 was strictly a prep package that centered on optimizing the engine for LPG. These were compression, timing and valves IIRC. The vehicle was still delivered as a gas vehicle and the final conversion was performed locally.

Your truck sounds like it was a fleet conversion ready to run truck from the factory.

[Propane350]

Originally Posted by SS Tim

If there is more than the propane prep option on the SPID I would really like to see it. Actually I'd like to see the SPID either way!

The factory offered LPG converted engines and we had a thread running last year if you want try searching for it.
But the public RPO L56 was strictly a prep package that centered on optimizing the engine for LPG. These were compression, timing and valves IIRC. The vehicle was still delivered as a gas vehicle and the final conversion was performed locally.

Your truck sounds like it was a fleet conversion ready to run truck from the factory.

I know I've got pictures of the carb, diaphram and condenser all lays out on a table, somewhere, but at the moment all I can locate are these pics of the original engine and tanks.

[SS Tim]

Right I understand the posted pictures of the throttle body, mixer and tanks you posted and am very familiar with how the system works (and replacing diaphrams). It is the SPID or option label on the glove box door you refered to earlier I would like to see. Also if it is a full factory installation I would like to see the engine tuning label if it is still there under the hood. Saw your post on roof rust very typical of your area unfortunately.

[Propane350]

I've got a pic somewhere. If I can dig it out I'll post it.

[BLACKLINE61]

Growing up on a ranch in central cali we converted all of our pickups onto LPG setups that were from a local propane company. We had a couple 72 chevys c20's my grandfather bought new and immediately converted over. The engines themselves would have 300k+ miles on them before rebuilds were necessary and usually went thru several truck bodies before spun bearings or something else terminal would go wrong. Its amazing how clean and how long the engines will run on propane with no carbon deposits or noticeable wear to the valves/cylinders... keep that setup IMO!