I just bought a 1979 f250 supercab long box 4x4. It has a 460 in it that runs on propane. I have a few questions I was hoping you guys might be able to shed some light on:

- What kind of transmission is most common with a 460 engine in these trucks? I think its a 3 speed and was assuming it's a c6 but I'm not sure.
- I was planning on using this truck in the winter but was wondering what I need to do (if anything) to make it work with the propane?
- Is there anything special that needs to be done maintenance wise when running propane?
- Is there a factory block heater that I can get to use on this engine or will I have to buy something else to warm the coolant before I start it in the winter?

I'm sure there will be more questions to come but that's all I can think of right now. Let me know if you have any suggestions as well.

Thanks

 

Call the experts at Got Propane Inc.: Propane Conversion Kits

 

did you talk to the guy you bought it from? He obviously has had this set up for a while so he should be able to answer your questions.

 

One of my summer jobs (30 years ago when I was a stupid kid) was that I made conventional gas tanks for trucks and RV's and helped my boss do a few propane conversions.

As I remember the engine coolant ran through the heat exchanger to "Warm" up the gas but I live in sunny California so I'm not sure how a propane heat exchanger would work in freezing temperatures. I would only guess that it would still work when it's cold because its still warmer than the compressed gas. I never had an issue with this one. Maybe someone could chime in.

Propane is pretty low maintenance as I remember. It burns cleaner than gas so your engine should have less carbon buildup and your oil would last a little bit longer. You would have check hoses and fittings for leaks if they are old and cracked.

Propane is nice because you will not need any smog control devices (If you are running straight propane) and you can get better performance and mileage.

The downside is availability and it's a real pain if you run out of gas. You would most likely have to be towed to a propane dealer. Also fuel capacity is an issue unless your tank is on your bed and you don't need the cargo space.

I'll bet you have the C6. Post your VIN and we can check it for you.

 

if you experience cold weather where you are, you will need a good block heater (the factory one is built into a freeze plug). otherwise, just the usual. good battery, keep the ignition system in good order. and enjoy. hot tip if attempting to start it in extreme cold (-40 or colder) pouring some boiling water on the vaporiser regulator (round thing with the heater hoses attached) can help get it going

 

Another question is if the truck is straight propane!? I ran a dual fuel system for several years, with a manifold adapter plate. You had to manually turn on or off each system, but the bonuses were that you had a cold weather start-up and fuel pressure from any angle. (Keep in mind that this was a Jeep) Propane at the time was the cheaper fuel source for me so I ran it over 70% of the time. I could get 5-7k per oil change and the spark plugs didn't need changing for the 5 years I had the rig, which when you consider the low speed, high torque multiple attack angles that Rock crawling requires always amazed me. And it runs so much cooler. The major Issue I had was the tank freezing up in the summer. I had to install a thermal wrap on it to stop that completely.

Keep us posted on your MPG too it should be better that with Gas, but I couldn't tell you how much in a full size truck.

Now I'm curious and might look at making the swap back myself!

 

i live in northern michigan, and all of the schawns delivery trucks run on propane up here. i also work in the one shop around here that is contracted to service them. the point i am getting at is that they change the oil only once a year and run royal purple in their machines. they run about 26000 miles a year on these things. just a little fun fact.
as far as heaters go for cold starts , im not sure. i havent gotten that far into the fuel systems on these. "only worked there six months"

 

I am very biased as my family owns and operates a small propane company here in our area. All of our service trucks, quite a few of our personal rigs and many customers rigs are set up to run propane. A mix of strait and dual.

My weekender fun truck is a 1979 4x4 Crew with a rebuilt 400.

I have a 100 gallon tank in the bed and use this truck for camping, hunting and other recreation. The best part about it (for me) is that I have installed adapters so that I can run my grill/heater/lamp and refrigerator from my tank when camping. I don't always bring all four, but being able to run them is just great. I'm currently restoring and old Alaskan non cab-over and long-bed dent trailer to carry it that will eventually be painted to match my rig. I will make some longer hoses to run its propane appliances off my truck tank when I don't feel like "roughing it lol" in just the truck. Or when the family wants to tag along.

If your engine is "tuned" or built to run on strait propane you can get increased mileage and keep your power the same (some reports of small gains).Also if the engine was built for propane it will most likely be minimum 9:5 or 10:1 compression. The propane races and hot rodders push 13:1+. If it was just slapped in or your dual fuel you "may" experience a slight power loss. This is typically because the engine is tuned/timed and set up to run gas. Propane burns differently and adjustments should be made. My truck is dual fuel. I built this truck to be an extreme camping rig (sort of an expedition rig) and did the bronco gas tank swap and my tire swing out has 3 5gal jerry cans on it. So with 100 gallons of propane, 35 +15 (50) gallons of gas my pissy 10 MPG gets me around 1500 miles of range. Of course its less since I use the propane to run other things and I dont always drive with a light foot. I found a happy balance when setting tuning my truck and did some other modifications to boost the HP so I really don't notice any power loss issues. I know this isn't dyno info and just redneck "thinks and feels" so I'm sorry for that. On real cold mornings I have had to switch to gas to get it start, only happened once though and the truck had been sitting awhile. Nice thing is though that if you rig is set up right its a simple flip of a switch then just flip it back over once your all warmed up. We do get a few feet of snow here and hover a couple weeks around the zeroish mark but nothing incredibly cold like some poor suckers out there. A block heater could probably solve some of these issues. I don't run one personally and don't believe any of our shop rigs do either.

Many of the positive attributes have already been mentioned and they are true. Schwanns trucks across the nation are on propane. We fill the one that runs in our area and have talked with him about it allot. The oil, and entire engine runs with very little carbon buildup anywhere. Our mail carrier converted her Chevy Celebrity 230k miles ago and her little tank just keeps on a running. Also if your truck is not a daily driver and my sit like mine does you don't ever have to worry about the gas going bad. No stabil needed. That is of course if it is strait propane. I keep my gas tank low and do use stabil as I only add gas when going on a real long trip. Many guys with old restored show style trucks have converted to propane for this reason.

If you live in a rural area and have propane at home, fill your own truck up. Find a local propane guy to tell you how, its not hard and many of us have them at our own house. Its maybe $100 is parts to make your own home fill station (not really a station, just a hose with the proper fittings). Propane is usually 1/2 the cost in the summer. I have a 1000 gallon tank at my house which I don't need, I really could get by with a 500 for my families usage but I like the 1000 because there is no chance of me running out in the winter and paying the higher cost for a fill. I fill my tank in the summer at around $1.50 a gallon and run all year (both home and truck). For example right now in we charge $2.95 to get filled up at our shop, however if you have a 100-500 tank and we do a home deliver it drops to $2.35 a gallon. If your 1000 or larger its currently $2.10 a gallon. 2 years ago my retail price for my 1000 gallon fill was $1.20 a gallon. Any of those prices I just posted beats gas prices in my area, some by allot. And again, I'm bias because what I pay is less then what I posted, those are the retail prices from our company.

There are many places that can fill you up. Many places are just stupid and don't know how to fill vehicles (even though its the exact same as the little 5gal bottles they fill everyday). I built several adapters that encompass pretty much every type of connection different propane companies could use to fill. I keep them in my truck "just in case" I ever run out. I have made these same adapters for customers and they have told me that in a couple cases they had to beg and plead but once they showed the place the adapter they were able to get a fill.

Hank Hill is my Hero. "Propane and Propane Accessories Bobby". There I said before any of you guys did.

However propane is pretty cool. House back up generators, can get large underground tanks (no prying eyes) and they make almost every propane appliance you can imagine. And unlike many other fuels, it doesn't go bad. So for you end of days or survivalist types, it should be on your list.

If you have any real technical questions I can ask my Dad as the propane side of the business is his baby. I'm really just an end user with a little experience and not much technical data runs through my head when it comes to propane.

Hope that helps you even a little bit.

 

Wow!! This site is great, there is a ton of knowledge here! Thanks for all the suggestions guys. The reason I posted these questions is because the previous owner only had the truck for about a year and the guy before him did the 460 swap with propane. Most of the questions I asked him he was unable to answer.
As far as running gear the truck is set up to run straight propane and has a large tank in the bed and a twin tank under the bed by the bumper. It doesn't even have a gas tank on it. The previous owner said the truck has 10:1 or 11:1 compression but was unsure, all I know is that it's got way more power then I was expecting out of a propane rig.
I will post the vin and some pics in the next day or two as well as I'm sure you guys would appreciate that!

Keep the information coming you guys rock! This has to be one of the best forums anywhere!

 

So how are you guys computing and paying road use taxes? This might be extremely cumbersome to someone running duel fuel.

 

Good post there Kodiak. You got Rep's from me for that.

Quote:
Originally Posted by 76f350spercamprspeal

Welcome to FTE, Best Damn Forum EVER!
------------------------
Here's How to Post Pictures:
1. Login to FTE.
2.Click User CP (In the Top Left Hand Corner)
3.(On the Left, There will be a list, The 5th Option Down, will say "Pictures & Albums) Click That.
4.Then, Click Add Album, Enter a title, and description, if ya want to.
5. Click Upload Pictures, Then click Browse, Locate the Files of your truck. (You can add 3 files at a time)
5. Click Upload.
6. Add a description to the individual pictures, then click save.
7. Add more files if ya want.
8. Click The Picture you want to post, it will give you two codes at the bottom, Right Click The Second one (It say's BB Code, Then Say's [IMG]http:blahblahblah...[/IMG])
Then, Once that is highlighted, Right Click, Then Copy, Then Paste it into your post.
You can add up to 30 Images in one FTE Post.
If, Ya need any help, Don't hesitate to ask.

 

Now you guys have me thinking about converting my "Candy Cane" to propane. Gas here in the Bay Area is currently at $4.15 a gallon for supreme which my truck requires. My 2 concerns are,

1. Availability

2. Where to mount the tanks? I don't want to use my truck bed. Can I get 45+ gallons of usable fuel with just the tanks under the truck bed and how would I fuel them up if I have multiple tanks? What has changed over the years since I was doing conversions?

 

At 10:1 or 11:1 your truck is designed to run on propane (basically) or super gas should you convert back later. One day 60k miles from now when you pull your heads for whatever reason you will be extremely happy you purchased a propane rig.

Ray, In Washington State where I live to run a vehicle 100% on propane they charge roughly $400 a year. That is a little steep in my opinion and since I'm dual fuel maybe I'm just redneck enough to say "what propane" and pay my normal $79 a year for tags. "Oh that big tank in the back of the truck? That runs my grill when I go camping". Now I'm not saying that is right or that everyone should follow this model but it is another reason why my personal truck is dual fuel. With the adapters I run I can make the case that I do indeed use it for camping and with the flip of a switch my truck is on gas.

NBC-Steve, With modification you can mount tanks anywhere. They make propane tanks in all different shapes and sizes. The think you have to make sure of when shopping though is that the tank your buying is rated for road use (DOT) approved and all that. You cant just un-hook the BBQ grill and throw it in the bed of the truck. Although with the right connections it would work, its not legal. And even my country butt doesn't play with that one. Many of the forklift tanks are road worthy and compact in size. You can run several linked together so if you found a spot here and then a spot there they will work running in unison. Since you can run a remote fill you can realistically put the tank anywhere it will fit. Another thing to keep in mind when tank shopping is that propane tanks are only filled to about 80% of their rated capacity.

So, if you buy a 100 gallon tank it will only be filled with 80 gallons of propane. So in my original post I stated I had 100gallons of propane, this is because I have 120gallon tank. I just get used to stating that its a 100gallon because that's what it will hold.

I looked at doing what your describing Steve and thought about removing my gas tank as I could fit a 50 gallon tank there then build a skid plate to protect it. Since my crew is a short bed and I never really used it anyways I went another direction. I have seen guys though install two lay down 30's in the bottom of large diamond plate took boxes. For reference my 120 gallon tank is about the same size as a large diamond plate tool box.

I'm not the most computer savvy but I will take some pics of my set up and post them so that it makes more sense.

 

A friend of mine used to have a 77 ford, cannot remember what motor it had but it also ran on propane, every winter he had to thaw out the gas lines repeatedly

 

Ive been using propane, LPG for a few years now, I love it! I use my truck primarily in the winter, it is straight propane, has a distributor recurve for the fuel, and a hot ignition(better than stock).
For the cold mornings, or just about any start, mine has a *choke* which is just an electric valve that is plumbed into the converter, triggered by 12v, and then sucks propane vapor into the engine via a vac. line. So it gets extra fuel when needed. Works great, starts in any cold weather!

You do have to think ahead for refueling, however its not bad, mostly. Check pricing for refuels, in case you run out, for having a truck come by to refuel, vrs. a tow bill to a service station. There is also a *jerry can* that could be made, just a hose with fittings to adapt a propane bbq tank to the fill of the vehicle tank. Hook up adapter, open valves of both tanks, and hold bbq tank upside down above vehicle tank. Havent tried it yet..

Another handy item, a fast idle solenoid, I believe mine was from a cadillac, just modded it to fit, easy wiring to a dash switch of choice. And or, if you are crafty could rig up an old choke linkage to the fast idle cams of the throttle body plate-if they are still there.
Good luck, and enjoy!