i was wondering if anybody has ever converted their car/truck to run off propane as their main fuel supply? if so how did you do it and did you have to change any engine internals?

iv been thinking about doing this but i am unsure of how to go about it. if i should just add propane to the unlead gas im useing now to better gas mpg or to run 100% propane.

if i did go 100% propane how would i keep the gas from leaking out of the carb and how would i get to to flow more with the throttle?

 

I have never seen it personally, but read about it every now & again on here.

I think adding it to just any engine may not be best. Propane works better on higher compression engines, requires a huge fuel tank (usually in the bed) and refilling at propane dealers only. A different fuel metering device is required from your carb. There are some that can switch between gasoline and liquid propane.

Prolly better to rebuild a high compression engine to run on it. Don't know why some of the older diesels wouldn't make good candidates.

Keep digging, you will get it figgered out. Engines are claimed to run much cleaner with it.



John

 

yup, much cleaner and cooler. and ive never heard of the high comprssion thing. thanks for the info.

 

Her you go, I have never installed one or used one but have thought about it.


http://www.nashfuel.com/kitimages.asp?ID=69953438639641

 

Here's a source: Propane Conversion Kits

If desirable, you do have the option of going dual fuel if an electric fuel pump is installed. Turn on the propane solenoid, switch off the electric fuel pump, and then the propane will take over. The propane "hat" fits over the carb. EZ.

A large pressure vessel (tank) is needed to have any meaningful range so say adios to some bed space. The rock crawlers can get away with lil ones cuz they go slow and not very far.

Better figure out the ROI (return on investment) to determine how long (in vehicle miles traveled) it will take to recoupe the cost of conversion.

 

If you do decide to go with propane I'd be very interested in hearing how it turns out for you, I've been interested in doing the same thing.

Sam

 

In the early 90s my buddy had a new F250 with a propane tank in the bed. It had the dual fuel option and could go 600 miles on a fillup, propane and the dual gas tanks. He pulled a 5th wheel so the bed thing didn't matter. It had the 460 with the low compression truck engine and it worked great. We'd go to Baja together and he didn't have to fill up at all in Mexico where I would several times and I hold 43 gallons in my 68 camper special with a 12' slide-in camper.

 

hmm sounds about like what ive heard. so an engine can run off propane without and modifications? eletric fuel pump and solenoid for the propane... sound easy enough. i have a tank i can convert to propane and the lines and stuff should be easy. all i dont know is how i would hool it up to my original carb. would i have to get a special kind?

 

TaborCT: Go to www.gotpropane.com and take a look at the parts included in the kit. The propane is discharged through a hat that mounts over the existing carb.

 

In 1990 I converted a 302 1973 Bronco to straight propane. Got rid of the carb altogether and it was replaced by a 'mixer' which essentially does the same job as a carb. There is also a device called a vaporizer which converts liquid propane from the tank to gaseous form and it is like a pressure reducer too. Vaporizer goes between the tank and the mixer, usually very close to the mixer. There was also a safety device called a lock-off valve which would stop the flow of propane altogether unless there was some manifold vacuum. That went just before the vaporizer. I put the tank between the back seat and the tailgate.

I drove the Bronco on propane for 11 years (daily driver) and loved it. Here in BC you can get propane at many gas stations so that isn't an issue, plus it is about 2/3rds the price of gas. The truck would just fire right up and purr like a kitten even in icy cold weather; with a gaseous fuel no need for a choke. On a vehicle of that age with a carb to begin with, going to propane is definitely an upgrade. Oh ya - I did recurve the distributor as propane likes the advance to come in differently than gasoline.

The only downside is propane powered vehicles tend to eat exhaust valve seats so you need to install hardened exhaust valve seats which solves that problem. That and a tiny reduction in full throttle power but the better driveability and cheap fuel more than made up for the slight HP loss.

I also converted my 1967 390 CID mustang. With 10.5 to 1 factory compression ratio it didn't really like modern pump gas but propane is good to 11 or 11.5 to 1 without pre-ignition so that helped me decide to convert the mustang. That plus the very positive experience of driving the Bronco on propane for all those years. The mustang might not have been quite as quick in the 1/4 mile on propane but for general driving it was so over-powered anyhow I couldn't notice any difference.

I am looking for an F 250 4x4 right now and hoping to find one already on propane, actually going to check out a '94 F250 next week. Hopefully it will be good and I will end up getting it.

Not sure of the price of propane in the states compared to gas. Is it similar to here where propane is 2/3rds the price of gas? Also, availability... can you get it pretty much everywhere like here in BC, Canada?

 

I would love to convert my truck to propane and get better gas mileage. If I did I would try to conceal the propane tank/tanks inside of my tool box so know one would even know I was running propane instead of gas. My only concern would be getting into an accident and the tanks explode cause that wouldn't be good, but other than that it sounds like a good alternative to gas.

 

Ed, Can you address the higher compression notation? I had read recently that LP similar to diesel liked higher compression over lower compression engines to run on. What do you know about that?

We have so much oil, natural gas reserves in the US but our clean air government keeps us tied to Opec and inflated prices to keep us from using it.




John

 

Cost Management Solutions LLC - Home of the Propane Price Insider

 

This site is great: Alternative Fuel Fill Stations and Prices it shows most of the places you can get road grade propane, and the prices.

Here in Seattle the prices can vary a lot, but it's usually cheaper than gasoline, but not always! It depends on where you go, some want $2.50 a gallon, others want $4.50! A propane distributor (Ferralgas is a big name around here) usually has road grade propane and at the best price. Avoid places that only fill BBQ bottles like the plague, they'll charge you an arm and a leg, and half the other leg.

Sam

 

super duty 250
propane tanks are far safer than gasoline tanks. I took a course on alternative vehicle fuels and I still remember a video they showed where a crane was used to lift cars way up in the air (100 feet maybe, can't recall the exact distance) while the cars were running and drop them back to the ground. Many of the gasoline powered vehicles ended up with ruptured tanks and gas everywhere, some even caught fire. Not one of the propane powered vehicles had a tank failure. Think about how the tanks are made (I mean real vehicle propane tanks, not some forklift refillable bottle like that one web site recommends): gas tanks you could puncture with a small nail and hammer. Propane tanks, as they have to withstand about 100 PSI pressure are welded steel. I doubt you could get into one with a cold chisel and a sledge hammer without a good amount of pounding. (you could likely knock a valve or fitting off with a cold chisel and sledge hammer but if the tank is logically positioned in the vehicle (can be in passenger compartment or not) a crash is unlikely to knock off the valves or other fittings. Note: propane tanks mounted inside vehicles have to have their over pressure release valves vented to the outside of the vehicle)

Also - with propane you tend to get a bit worse mileage but the low cost of the fuel more than offsets that

rusty old F250 - what a great site with the locations and prices of alternate fuels!!! Thanks!

jo wiler - re compression, I only know that propane can work well in terms of not knocking, in high compression engines so I would think if one was going to build an engine just for propane it would be good to go with 10 or 11 to 1. I suppose that means maybe an 8.5 to 1 engine might be kinda weak on propane but I don't really know. My 302 bronco had 9.5 to 1 pistons in it plus I used 67 289 heads which had a slightly smaller combustion chamber volume but I can't recall what the final CR actually was. Just know I lost a bit of passing power on steep long highway grades but gained cold weather purring on startup and improved general drive-ability and big dollar savings.

TaborCT - I don't think you can convert any regular fuel tank to store propane. Propane tanks are pretty specialized. For the bronco I converted I just used an off the shelf propane tank ,can't recall the size but for the mustang I had to have a custom manifolded tank built (manifolded=2 small tanks with interconnecting tubes all welded together to act as one tank but fit into an odd space. Here in BC propane vehicles need to be certified before you can fill them up at a gas station. You need to purchase the appropriate parts, put them together according to code and have a certified installer be willing to inspect and certify your work. Believe me, they won't put their name to anything that isn't to code (think of the liability issues). I had the code book and before I started found a place willing to inspect and certify my jobs.

I was just talking with a place that does conversions a few days ago (thinking about the F250 I am shopping for) and the guy told me that for fuel injected engines they now do propane injection - drill and tap the intake manifold close to the existing gas injectors and the computer runs it. I wouldn't have a clue how to do that (although I imagine tank and some parts would be the same as what I used) The vehicles I had were both old fashioned carbureted, no computer vehicles so from my perspective much easier to deal with.