Newbie Fuel question

1941 - 1945, MB, GPW Technical questions and discussions, regarding anything related to the WWII jeep.
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moreirdan
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Newbie Fuel question

Post by moreirdan » Wed May 11, 2022 3:50 pm

I have a 45 MB and am wondering what fuel I should be using. I don't think there was lead free fuel in 1945 and I am pretty sure there was not 10% Ethanol in every gallon. I apologise if this question is old hat for many of the experts here. I ask particularly because I had a look in the fuel pump and there seemed to be a gasket in poor shape and I wondered if that was down to the fuel.
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parker007
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Re: Newbie Fuel question

Post by parker007 » Wed May 11, 2022 4:18 pm

use either pure fuel, or av gas if you can find. if your engine has not had hardened seats you need to ad lead if pure fuel

Ron D
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Re: Newbie Fuel question

Post by Ron D » Wed May 11, 2022 4:37 pm

Av (aviation) gas is 100 octane and super-expensive.
Mixing a gallon or two in a tankful is beneficial for the lead content, but it's dyed blue so don't let the Man catch you with it on the street or highway without wings.
You might need to adjust your tuning specs if you use it straight.
Regular 89 octane ethanol-free is your best bet, and getting real expensive by the minute.
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dinof
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Re: Newbie Fuel question

Post by dinof » Wed May 11, 2022 5:19 pm

I've been running my vehicles with gas that has ethanol for 20 years. If you have a choice
where you live, choose without ethanol. Regular is just fine. This isn't a 14 to 1 compression ratio
racing motor, so forget the premium.

From what I see here after many years on the "G" is folks that have dirty, rusty gas tanks and
fuel lines that create the most havoc. And then your issues move to carb issues as dirty
gas really messes with these jeeps. Just make sure your gas is clean, or you'll have more
to worry about than choices of gas.

Clean fuel is paramount. I do admit I add some Marvel Mystery oil to my Model A,
because the older guys swear by it in my club.
Dino Falabrino
On the "G" since 1998.
1943 GPW 102310 DOD 3-3-43
1928 Model A Roadster Pickup
1930 Model A Tudor
1968 Taco Minibike

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dpcd67
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Re: Newbie Fuel question

Post by dpcd67 » Wed May 11, 2022 6:25 pm

I use only non ethanol gas in all my historic vehicles. Easy to get here, even though this is where all the ethanol comes from (corn).
Yes, ethanol will eat old rubber, and gaskets. Fresh rebuilds with modern parts is necessary on carbs and fuel pumps.
If you leave ethanol gas in your tank for more than a few months, it will form jellyfish and gum up your system. I have an M37 that got that and needed an entire fuel system flush and carb rebuild.
I do not add lead.
All this has been discussed before; do a search of this forum.
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parker007
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Re: Newbie Fuel question

Post by parker007 » Wed May 11, 2022 6:44 pm

Ron D wrote:
Wed May 11, 2022 4:37 pm
Av (aviation) gas is 100 octane and super-expensive.
Mixing a gallon or two in a tankful is beneficial for the lead content, but it's dyed blue so don't let the Man catch you with it on the street or highway without wings.
You might need to adjust your tuning specs if you use it straight.
Regular 89 octane ethanol-free is your best bet, and getting real expensive by the minute.
right now at my airport that i frequent the avgas is cheaper than super at the gas station it is 5.40$ to 5.99$ at the gas station. but yes dont get cought putting in your car.

irakli
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Re: Newbie Fuel question

Post by irakli » Thu May 12, 2022 3:00 pm

I am adding lead substitute made by Wurth to gasoline to protect valves. There are other producers on US market.
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pgcf
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Re: Newbie Fuel question

Post by pgcf » Thu May 12, 2022 4:01 pm

My jeeps are all rebuilt for modern fuel. I don't have any options but Regular gas with Ethanol.

I only keep the tank about a quarter full unless I know I'll be doing more driving.

I add STA-BIL to all gas I put in the tank.

Have had no problems for 5 years.

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Re: Newbie Fuel question

Post by sjalbert » Fri May 13, 2022 7:13 am

I've been using regular pump gas for 30+ years. I keep the tank full to minimize condensation in the tank and regularly let the Jeep sit for a month or more at a time. Occasionally I'll remember to put some Sta-Bil in. The longest it sat was after Hurricane Harvey. When I finally unburied the Jeep in March 2018 the fuel had been sitting since the previous June (2017). Fired right up after I primed the carb. Key points are you absolutely want clean gas in a clean system. I replaced all the rubber hoses and gaskets 10+ years ago with modern materials.
Last edited by sjalbert on Fri May 13, 2022 9:07 am, edited 1 time in total.
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dpcd67
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Re: Newbie Fuel question

Post by dpcd67 » Fri May 13, 2022 7:19 am

Sitting a month is nothing. Ethanol gas will easily take that. It's when they sit for a year, like some of my vehicles do, that you can't use ethanol gas in.
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Buster1
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Re: Newbie Fuel question

Post by Buster1 » Sun May 15, 2022 5:26 am

All ethanol-free gas for my Jeep. But I’ve heard the Sta-bil that neutralizes ethanol in ‘regular’ fuel works well too.
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HankII
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Re: Newbie Fuel question

Post by HankII » Tue May 17, 2022 5:33 am

Joe Gopan always recommended Lucas Fuel Treatment.
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dinof
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Re: Newbie Fuel question

Post by dinof » Tue May 17, 2022 5:55 am

When I need gas, I first take my jerry can ( yes, it's clean inside) and fill my tank, and
then refill the can and if I need some more in the tank, I just add more there.

Why? I'm rotating my gas out continually to keep it fresh in both tanks.
Dino Falabrino
On the "G" since 1998.
1943 GPW 102310 DOD 3-3-43
1928 Model A Roadster Pickup
1930 Model A Tudor
1968 Taco Minibike


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