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Ok guys I have been using non oxy gas in my M37 primarily because is sits most of the winter months up here in MN. I was just wondering if anyone here puts a lead additive in their gas also for protection against friction??
Steve
Fuel in the M37
Moderators: Cal_Gary, T. Highway, Monkey Man, robi
Re: Fuel in the M37
No need for the lead additive. The stock engine does just fine on unleaded.
I do avoid ethanol blended gas, however. The shelf life on it is abysmal, and the ethanol can eat at some of the older rubber parts in the fuel system (modern rubber and synthetics do a bit better with ethanol.)
Ethanol is also Hygroscopic: it absorbs moisture from the air. If the tank it which it is stored is not completely sealed from the atmosphere, air gets pumped in and out as the air and fuel in the tank heats and cools. As new air is introduced, the ethanol pulls moisture out of that air and the ethanol and water combine. If enough water is introduced, the ethanol/water mix settles out, sinking to the bottom of the tank. This ethanol water mix is corrosive: it's not good for carburetors, fuel tanks and other engine/fuel system parts. It may take some time for enough water to get introduced. A typical motor vehicle tends to run through a tank of fuel before this can happen. However, vehicles which do not run through the fuel in their tanks regularly can suffer. Modern vehicles have less of an issue, since hey have no carb and have been designed with ethanol fuels in mind.
I do avoid ethanol blended gas, however. The shelf life on it is abysmal, and the ethanol can eat at some of the older rubber parts in the fuel system (modern rubber and synthetics do a bit better with ethanol.)
Ethanol is also Hygroscopic: it absorbs moisture from the air. If the tank it which it is stored is not completely sealed from the atmosphere, air gets pumped in and out as the air and fuel in the tank heats and cools. As new air is introduced, the ethanol pulls moisture out of that air and the ethanol and water combine. If enough water is introduced, the ethanol/water mix settles out, sinking to the bottom of the tank. This ethanol water mix is corrosive: it's not good for carburetors, fuel tanks and other engine/fuel system parts. It may take some time for enough water to get introduced. A typical motor vehicle tends to run through a tank of fuel before this can happen. However, vehicles which do not run through the fuel in their tanks regularly can suffer. Modern vehicles have less of an issue, since hey have no carb and have been designed with ethanol fuels in mind.
1951 M37 "Brutus" w/Winch and 251 engine
Re: Fuel in the M37
Thanks for a well written answer to the fuel question, and description of the effect ethanol has on fuel systems!
MVPA Member #23780
1942 Chev. 1 1/2 Ton Dump Truck
1951 M37 W/W, & Field Radio
1953 M43
1958 Navy CJ3B
1942 Chev. 1 1/2 Ton Dump Truck
1951 M37 W/W, & Field Radio
1953 M43
1958 Navy CJ3B
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outpostm37
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Re: Fuel in the M37
Here is Arizona, I use the 87 octane, (it is oxygenated fuel) plus Marvel Mystery oil and StayBil. The Marvel Mystery oil really shows its stuff in the 1976 2F Toyota FJ40 Landcruiser. The Aisin carb has a fuel cut-off valve that operates properly with the Marvel Mystery oil. Without the MM oil. the engine will give a "backfire" out the exhaust. As far as the M37, it runs so much smoother with the MM oil. Your vehicle, your call.
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RedUtilityTruck
- PVT
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- Joined: Sun Aug 02, 2020 3:37 am
Re: Fuel in the M37
How much MM Oil per tank of gas do you use?outpostm37 wrote: ↑Thu Aug 18, 2022 4:27 pm Here is Arizona, I use the 87 octane, (it is oxygenated fuel) plus Marvel Mystery oil and StayBil. The Marvel Mystery oil really shows its stuff in the 1976 2F Toyota FJ40 Landcruiser. The Aisin carb has a fuel cut-off valve that operates properly with the Marvel Mystery oil. Without the MM oil. the engine will give a "backfire" out the exhaust. As far as the M37, it runs so much smoother with the MM oil. Your vehicle, your call.
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outpostm37
- CPL
- Posts: 128
- Joined: Sat Oct 28, 2017 6:07 pm
Re: Fuel in the M37
I follow the instructions on the back of the bottle of the StaBil. They know their product best.
Re: Fuel in the M37
a year ago, ran out of non-ethanol, which is avail at a station about a mile from my home. Accidentally fill my gas can with ethanol fuel, and after about 15 minutes of that in my decade old back pack blower, it just failed. Had to put a new carb on it: the gaskets were so swollen up it was ruined. Is OK in modern cars but nothing vintage like my truck. Hal