Propane engines....

[noe-place]

I was re-reading an old article in Mothorhome Magazine where an engineer was discussing the feasibility of replacing the gas engines in rv's with propane powered engines. Anybody have any recent data on such research?

[MEXICOWANDERER]

I had a hammer & chisel Onan 2,500 watt 1,800 RPM generator that was propane. I loved that unit. Carried it in the back of a pickup. Started easy, ran well, and I used it for 5 minute to half hour jobs. It had stator winding starting so I started and stopped it to save fuel. What a sweetheart it was. During the sub zero winter I ran it on SAE 10W straight weight oil. Ever see 80hz powering a pair of Associated wheeled battery chargers? The Onan laughed it off. The days of getting away with murder. Linking a marine 8 volt battery with a similar amp hour six volt battery in series. When I connected those 2/0 jumper cables to a vehicle IT STARTED! Sub zero F, and the jumpered vehicle would SHIVER as the starter motor spun that engine. Can't do that now.

[red31]

MEXICOWANDERER wrote:
How many of you folks have owned, driven, and maintained a motor vehicle with a dedicated LPG motor fuel engine?

Not me, my '96 Chevy S-10 was converted to be able to use either gasoline or propane. A 50+ gal propane tank allowed for 46 gallons of propane and the 20 gallons of gas gave me a 1,000+ mile range. The state and feds paid for most of the conversion. 80,000 miles on propane over a 5 yr period. Propane stores are generally closed on Sunday. The variety of filling equipment and personnel from spot to spot was interesting.

[hypoxia]

I have owned several bi-fuel pickup trucks and a 24' class C motorhome Ford 460 and have a LPG fueling station at home, something over 10,000 gallons pumped. In the old days it was an easy conversion and LPG was cheap, now the conversions are required to meet EPA standards and the cost of LPG has risen. The current systems are so complex that parts repair or replacement is very expensive. Compressed Natural gas has similar problems as it requires large tanks under pressure and unless you are driving a tanker you will spend a lot of time refueling. Cross country travel with CNG would be a pain. LPG is available everywhere.

[subcamper]

Propane (or natural gas) engines will last longer before rebuilds. In a gasoline engine, unburned gas in the combustion chamber will wash off the lube oil on the cylinder walls until the next stroke replenishes the oil. This cycle eventually wears out the cylinder bore/ piston rings until it starts burning oil and losing compression. Propane/natural gas doesn't wash the cylinder walls of gas, so the engine lasts longer. This is also why dieseld typically last much longer than a gasoline engine (before a rebuild is needed).

There are a bunch of natural gas vehicles running around here, mostly buses and company fleet vehicles (such as garbage trucks).

Steve

[ol_Bombero-JC]

K Charles wrote:
You don't need to change the engine, a gas engine will run on LP gas with only modification to the carburetor and timing.

During the last "gas crisis" 1979(?), there were numerous companies doing a brisk business in propane conversions.
Some were "dual fuel" - but most were propane only.
Plenty of options of tank sizes. Yes, they were doing cars also - with tanks in the trunk!

Only limitation -for gas powered RV conversions- was tank placement.

Two guys I worked with had propane powered vehicles.

#1. Chevy pickup - towed a 5th wheel.
Fifty or 60 gallon tank (been a long time - may even have been 80) mounted cross-ways just behind the cab.
It was powered by a 454 V8 - he said he never noticed any loss of power after it was converted.
He traveled a lot and never had any problem locating a bulk plant.
In a pinch, a smaller dispensing facility was a back-up.

A few years after things returned to normal, he converted it back to gas, eventually sold it to a neighbor.
Original owner was very meticulous - pickup was in pristine condition.
But it had high mileage. The neighbor thought a rebuild was in order. He was surprised at the lack of wear or sludge - said he should have left it as is, and "untouched".

#2. Dodge van - IIRC it had a 318 V8.
Just his "daily driver".
Owner had a 50 (or 60) gallon tank *inside* the cargo area.
Yeah - Yikes!
A death-trap if he ever had a "problem" - and we told him so!
Never had any problems, and also sold it a few years later.

IIRC - neither one made any timing changes - and the propane-only "intake" was way simpler than a carburetor.

~

I run my *portable* gens as "tri-fuel".
Ran a lot of load tests on my Yam 2400is, as I had used it previously for several years as "gas only" before conversion.
No noticeable power loss on propane - but readily apparent (as expected) on natural gas.

BTW - no plan to run 'em on gasoline again, unless absolutely necessary.
(Ethanol can be PITA!..:(..)

~

[64thunderbolt]

If you want to see the diff in power and mpg take a look at an LP gen. An Onan 4000 on LP is rated @ 3600 and are very thirsty

[sum1]

We once ran a converted 1 ton flatbed truck. It was gutless compared to its gas powered twin.

[robatthelake]

About 1980 , in Canada there was an incentive to buy Propane Powered Vehicles.
Heck Gas was about $1.20 per Imperial Gallon Nd Propane was about .30 cents.

It made perfect sense ,until the Tax Man got wind of the situation. Propane shot upon in cost to almost the same level as regular gas! Killed the Industry overnight!

The difference in power between Propane and Gas isn't a big deal during normal driving ! Propane however burned cleaner and Oil Changes became less frequent..Engines lasted longer and the Air We breathe was a little bit cleaner.

So what killed it?

Government..Yours and Mine!

Greedy bunch of hypocrites !

[noe-place]

Great discussion y'all. I learned something. Thanks.

[free_radical]

heres some interesting info on propane natural gas in Canada

https://www.google.ca/search?client=safari&hl=en&q=http+www+wheels+ca+news+with+gas+prices+so+high+w...

[wa8yxm]

Regarding the tax man mentioned above..

I remember when Gasoline was less than $0.25/gallon (Oh were those the days)

Some years ago I pulled into a Marathon station (On Telegraph RD in Redford, TWP, (MI) just north of I-96 (I think the cross street is Arcidia) and there was a sticker "You are paying 87 Cents in tax on each gallon)

And the taxes have gone up since.

As someone up-thread said, Propane is a nice fuel but you need a lot of it 4 gallons of Propane =about= 3 gallons of gas. You need large heavy tanks to hold it (Adding to the weight of the vehicle) and in the event of an accident it is much more dangerous should it leak out. Not that gasoline is not mighty dangerous if leaking itself.

Now Natural Gas is a reasonable choice, but the same statements (save for the ratio) apply.

[Chris_Bryant]

Propane injection, on the other hand, is quite popular, where the propane is in addition to the normal fuel.

[MEXICOWANDERER]

How many of you folks have owned, driven, and maintained a motor vehicle with a dedicated LPG motor fuel engine? With 100,000+ miles of "experience" plus the added at-no-extra-cost bonus of having done all of the conversions myself I am firmly convinced that LPG has "it's place" and is suitable for a small minority of applications as a main motor vehicle fuel source. Almost all of the so-called technical articles I read about LPG motor fuel conversion were biased.

Why did I do "it"?

For decades, gasoline in Mexico was a joke. Seventy or eighty octane at best. Dirty, and the dispensers were rigged. So LPG (butane in the tropics) was a viable option. So I converted. My one-ton had a pair of 83 gallon motor fuel tanks crosswise in the bed vertically stacked.

I had to spend A TON of money having an engine specially built for LPG use. 12.5 to 1 compression, a special camshaft, fuel injection cylinder heads with giant valves, hardened exhaust AND intake valve seat inserts. A huge tubular aluminum intake manifold and 2-1/2" exhaust. It all worked but there were catches - like the four hundred dollar five tube count radiator with 32 fins per inch. The engine oil cooler. The engine STILL ran warm when the weather got hot.

With ALL of the modifications, the engine had a power level similar to that of a standard Chevy 350 engine. It got decent mileage, around 12mpg empty. But I learned LPG fuel engines tend to leak a lot more oil. So I had to tear things down and use a two hundred dollar silicone rubber racing engine gasket kit to stop oil leakage.

With decent gasoline being introduced with MAGNA SIN back in the early 90's, the "need" of my using LPG vanished.

In February 1995 in the midst of a peso devaluation I paid the equivalent of thirteen cents a gallon for butane. Those days are long gone. LPG costs two dollars fifty cents a gallon now.

[powderman426]

Ozlander wrote:

powderman426 wrote:
A gallon of LPG has approx. 75% of the btu's in a gallon of gas. Where I live a gallon of lp is about $2, so it would be cheaper than gas, :B

It may be cheeeper than gas, but when the tax man shows up and wants his money plus a fine, it won't be.

If your buying from a legitimate source, there are no tax problems and it's perfectly legal.