What fuel is best to use?

[Chris Preston]

'Afternoon All,

One of our Museum members has raised a good question (and one that I've thought of myself, on occasion) - what fuel should we be using in our vehicles?

We have three CMP's from the Second World War, five Jeeps from 1946 - 1968, several M-37 based vehicles, one Daimler Ferret (which we're already using Premium Fuel for) and several none-operational vehicles that we hope to have running someday.

Also, what's the opinion on additives such as lead supplements and octane boosters?

Cheers,

Chris Preston,
Victoria, BC,
Canada

[Bruce Parker (RIP)]

Highest octane you can get as it is usually is the only one that doesn't contain any ethanol, but check to make sure. Ethanol softens the old rubber in your fuel pump and hoses. Then always keep the gas in the tank for no more than 4-5 months because any longer and it tuns to an un-burnable turpentine that will also clog your carburetor. I've been told gas stabilizer intended to lengthen the life of ethanol blends won't work on non-ethanol 'high test' so keeping it fresh is your best bet.

The lead substitute is meant as a lubricant for regular, non-hardened valves (which most CMPs are either because they are original or rebuilt that way). I don't use it but probably would if I drove my vehicles more.

[rob love]

Having been through the trials and tribulations of stuck needle valves, excessive pump failures, cracking rubber lines, and dealing with skunky fuel, I strongly suggest premium in anything with a carb. We had an in-tank electric fuel pump on a deuce actually stripped of it's coating in the space of a year, making the bottom of the fuel pump chamber an inch of sticky goo. The pump had to be replaced.

Edited to add: I forgot about the sticking valves. Seemed like my tractor was regularly throwing valve pushrods, especially in the winter. It now only burns premium for the past two winters and I have had no more sticking valves.

Ethanol is a gimmick and a curse brought to us by the corn lobby, and enacted by governments trying to somehow appear green. If you merely consider the fuel you will end up throwing away because of it going prematurely skunky, that alone should be enough to convince you to pay the extra 20¢ a liter for premium.

There is a reason why the owners manuals for any modern lawn mower, chain saw or other small engine states "Do not use ethanol fuel".

As for additives, since going over to the premium, I have not used any additives. Time will tell if that is the correct move. We are above 30°C these days, so if a vehicle was going to vapour-lok, now would be the time.

[Bob Carriere]

Getting harder to find but there is a list of vendors available on the web somewhere that lists. in Canada and US, which brands are really ethanol free.

I am lucky to have a Card Lock system available in my rural area that carries high test with no ethanol....... use it for everything gasoline run. I always leave my tanks full when the vehicle is stored for the Winter. All my gas is stored in plastic containers and keeps well over a year tightly sealed.

Many antique car forums in the USA have discussed this issue extensively and have quoted reputable sources and all support Premium fuel and consider most fuel and oil additives as wasting money. Time and time again it has been pointed out that changing the oil on a more frequent / regular basis ( and mileage alone is not a good criteria) is more important than using premium oil. Cheap insurance as they say.

Cheers
Found one site https://www.pure-gas.org/

[cletrac (RIP)]

A flat tappet cam like old vehicles use has to have a zinc additive in the oil or the cam lobes won't last. There aren't many oils that have it but quite a few heavy duty diesel oils do have zinc.

[rob love]

Good point on the oil. There is a chart on a site somewhere that compared the Zinc levels of diesel oil. Walmart oil actually came out as one of the higher levels, although that may vary since it may well be "jugged" at regional contractors.

Another option is the high mileage oils. There are a number of them at Canadian tire these days. Most or all brag about their increased levels of Zinc.

You can also add an additive like ZDP. I ordered 10 bottles off ebay which will last my little fleet for a while.

[Chris Preston]

'Afternoon All,

Many Thanks for your insight and suggestions with this topic - it's pretty much what we thought, but it's always nice to get confirmation from those who have more experience.

Cheers,

Chris - In Victoria, BC