Cheap Gas and Jeep Engines

I learned to drive on a 42jeep in the mid 1960s. Had a 59 CJ5 in 1969, the year my dad died. I remember him telling me that the jeep engines (both the L head and F head) were low compression engines and designed to run on just about anything for fuel. Heard stories of stale gas, gas/kerosene mix. It seems to me that I read somewhere that the jeep engine would run on 60 octane or less. Is there a thread of truth in this? Comments welcome.

Also the new pump gas has a considerable alcohol content as well as no lead. Is there a concern with gaskets leaking (carb and fuel pump) from the alcohol? I have had issues with my 68 chevy. Had new valve seats installed so I could run unleaded fuel.

Just wondering if anyone has given any thought to this. I'm wondering if it would be better to use some additive to the gas for the jeep to lower the octane and offset the alcohol?

Also, there is much concern in the oil department with muscle cars and flat tappet cams. The new oils are too slippery and don't allow the tappet to rotate, causing the cam lobe to round down. Have to add cam break-in lube to the oil for insurance against this happening. May not apply to jeep engines that much, but I thought I'd bring it up for discussion.

Comments welcome:?

 

im sure over time the alcahol is not benefitial to the system but im not sure its worth the extra dough for addative that may not do much to help.
As for the oil. Check out this page for all the info youll ever want to know
http://forums.pelicanparts.com/pors...motor-oil-thread-why-we-hate-cj4-sm-oils.html

 

Been giving the gas thing thought, what w/ all the ethanol drawing moisture and ruining entire fuel systems. Makes it hard to store gas for any length of time as well. Work is concerned with it as well, having a (2) 2500 (?) gallon tanks for the equipment and vehicles. They might be 1500 gallon but, either way, storage has become an issue. Head mech recently started treating the tanks with a product called Star-tron I think ( atleast the diesel tank).
I've heard suggestions like using Sta-bil, Marine Sta-bil, or the gas line anti freeze Dry Gas to avert moisture content. Not sure any of it will work. My next move next time I'm doing a fuel system will be to use a poly tank and some kind of plastic lines. Not original and that stinks but it's looking like that's the way it'll have to be.

 

I can say the Marine Sta-bil does help. I use it in my skiff. Dang thing doesn't burn any gas and the gas in the tank is more then 2 years old. Still running ok, though we have noticed it is starting to show signs of old gas. Buddy runs the stuff in his boat to try and keep the ethanol from messing up his carbs. Yeah he has had to do a set of carbs rebuild but the mechanic said it was a lot longer before the rebuild then a lot of people.

 

I fully agree !
One time back when I lived in Death Valley I got in a real pinch.
I lived alone in a miners cabin waaaaay out from town.
I needed fuel. I needed it desperately !
I dumped 4 or 5 gallons of pure Kerosene into my CJ-2A fuel tank.
I was simply amazed. It ran as good as ever on nearly straight / pure K1.
Before I got some real gasoline in the tank; I pulled a spark plug.
It looked very sooty. (not really so unusual for a Willy)
Anyway I encurred zero problems from doing that.
I certainly would do it again if need be.
Not to knock down the D-225 but I seriously doubt that a D-225 would take the K1.
Not to brag, but at least one time for me the L-134 Go Devil performed an even much greater
and a more amazing stunt than that one.

 

wasnt the old leaded gas only rated at like 60 octane?
edit: answerd my own question. It was actually much higher at 100-115 or so. Intresting

 

I heard that they could run off fumes from WWII vets.

 

Something I was reading last week listed 68 octane as the motor fuel needed for the L head.

 

Virtually any engine designed in the 40s would run off of crap 60 octane fuel, the compression on most of the old motors back then were the same or similar as the L and F head motors so its not really a big deal, Old John Deeres and Farmalls will run off of crap all day long that won't even start old Jeep motors. Coal oil, white fuel, watered gas, Kerosene, you name it you can pour it in and most of the old tractors will run off of it.
I do know my Dauntless 225 has run on fuel with no stabilizer that was 5 years old.

Low compression is the main key to running on crap fuel.

 

Regarding Unleaded vs. Leaded fuel do a search under "unleaded fuel"
Been covered lots.

Here's a link to get you started

http://www.earlycj5.com/forums/showthread.php?t=63597&highlight=unleaded+fuel

 

wouldnt worry about it. its mainly a problem in high compression engines with heat, and even then it takes some time to cause a problem under normal use. like 60k miles. in regard to the new fuel and water, i really dont see the problem. what do you mix in with your fuel to remove water? alcohol!! as far as gaskets and such, hell they used to run grain alcohol (moon shine) back in the day and it didnt seem to cause a problem, or at least not a big problem. and they were prob running 100% not this 10% crap at the pump

 

The engines will run fine with the alcohol but the problem is with the rest of the fuel system or on vehicles that sit for long periods of time. Alcohol is corrosive and also will attack rubber components that are not alcohol rated. Things like synthetic floats, rubber fuel hose, needle valve and seat, accelerator pumps, etc. can be eaten away or softened by the alcohol. Alcohol can cause accelerated corrosion in metal fuel tanks and lines as well. Best thing to do is to run the vehicles periodically with a change in the fuel or failing that, add a fuel stabilizer. Vehicles that run on high concentrations of alcohol have components designed to work with it. Look through a Jeg's and Summit catalog and see how many components say "will work with alcohol" and then look at the cost difference.

 

Kerosene ....I once ran my 51 cj3a on weed eater fuel (oil mix 32 to 1). ran great but left smoke trail down the road. Everyone knew where I been by my trail.

 

I mainly agree with Mcruff's claims and the relatively high compression ratio of 9.0/1 is why I don't expect a D-225 to burn kerosene.
However I don't really agree with his claim of burning water/gas.
Limited quantities of water might go through any engine but it certainly is not burning.
Also realize that fuel stabilizer is a completely seperate issue from octane rating or BTU's.

 

Is this also true of the isopryl alcohol in Dry Gas and other gas line antifreeze additives?

 

That should have been watered/gas as stated in my post!

 

Very small amounts typically don't cause a problem if the directions on the bottle are actually followed. Remember you're adding what, 12-16 oz. per 15-25 gallons of fuel if the directions are followed? In other words, 6-8 oz. per tank full on an early CJ with the under seat tank. No big deal. The amount of alcohol in most fuels today are higher than that and that's the rub. Yesteryear's fuels had very little to no alcohol in them. Nowadays 10% is very common.

 

Check out the latest USEPA mandate - 15% "gasohol" is coming.

 

Seems to undermine Newton's 17th law, that one type of alcohol, iso, is used to combat moisture in the fuel while other alcohols attract it. I'm no chemist though........