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It's 8 degrees out. Seriously, 8 degrees. I can always get my M38A1 started. Maybe I have to play with the choke and hit the fuel pedal a few times, but it always works. Except today, when I had to use quick starter fluid. Even that didn't make it catch right away. I've never had these cold weather issues with modern vehicles, but I have owned a CJ5 and a CJ7 before, and both had a bit of trouble when it got really cold. What I'm wondering, is considering these vehicles were in even colder places sometimes, did they have the same issues?

I'll bet they did,hence the need for engine heaters.Living in the North ,we put engine heaters on anything we wanted to start in the cold weather.

Oh yeah, I didn't even think of that, they do have an engine heater for cold climates!

The arctic powerplant heater kit was issued to vehicles assigned where ambient daily average winter temps were 0 to -65. Minnesota, Wisconsin & North Dakota didn't usually qualify. Units based in northern tier states usually just installed freeze plug heaters and plugged them in.

The M38 engine heater was a nice piece of work that heated the oil pan as well as both batteries. The below zero installation spec gives an idea of the amount of heat it will output.
The dash mounted engine primer was discontinued during production but is a useful add-on for starting.
The dash primer was M38, was the primer provision of the M38A1 on the fuel pump?

Deadguy - you mentioned hitting the accelerator pedal during starting. I think it is a natural inclination to try to goose the engine into life that way. But remember the carb for a M38A1 does not have an accelerator pump so using the gas pedal does nothing to help start the engine and actually impedes carb function. Starting instructions are on page 33 of TM9-8014 and mention pulling the choke all the way out and cranking the engine until it starts, then pushing in the choke. But don't excessively crank the engine. Making sure the engine is properly tuned is important - carb, fuel pump, plugs all ok. Yes, a warmed oil pan helps tremendously.

The dash mounted primer is kitted for both the M38 & the A1. It's installation is required when you install the personnel heater kit, which is only installed in northern tier based jeeps.

The Army realized that the low utilization of these post war jeeps meant the fuel in the bowl evaporated during long term periods of non-use. The only purpose of the hand pump lever on the fuel pump is to refill the bowl in the carb anytime of the year. You can use this pump on the M38 and by the end of the service life on these jeeps that was the only pump stocked most places.

The M38 & M38A1 both DO have accelerator pumps. The problem is they are vacuum operated. That does not mean the engine has to be running for it to work. It means you must follow the simple directions in the operator's manual. Choke closed all the way helps the engine to create a lot of vacuum while cranking and this cranking vacuum will recharge the vacuum diaphragm chamber and give you a squirt when you move the pedal just once. Jeeps used in colder climates usually had the dash primer kits installed which helps out with this starting fuel issue. If the vacuum diaphragms are in good shape they retain sufficient vacuum when parked a day or so to give you one squirt but at 0 degrees that one squirt is not enough. If you intend to operate the jeep in the winter then it is foolish not to have a dash primer kit installed. The bulletin to disable them was not because they didn't do their job. It was because mechanics didn't maintain the primer pump properly and clean it's poppet valves once in awhile. Since these jeeps sat a lot in the 60's and 70's the poppets got gummed up. When they stuck open she would suck extra fuel all the time and run very rich or if the seals were bad in the dash pump she would suck air and run very lean.