I have a pull start blower from sometime in the 90’s. It’s a beast! However, I need to put a heater on it for about 10 minutes so I can reasonably pull it. Otherwise, it’s super difficult to pull and most certainly won’t start. Is there some maintenance I can do to make it pull easier without having to heat it? I’m not expecting it to cold start but it would be nice not to have to heat it as much and pull it real hard
I would try a 5w-30 or 0W-30 synthetic oil, to lower the pour point and viscosity of the engine oil. The 30 (warm) rating will give you the at temperature viscosity.
The synthetic oils provide better cold weather characteristics.
Your owner's manual will likely not specifically recommend this, because synthetics were not in as widespread use, and were not formulated as they are today.
A properly operating snowblower should not need starter fluid except in extreme (-20F and colder) temperatures. Using the starter fluid increases some wear, but more importantly risk of fire, etc.
Also, while you are at it, check the plugs, air filter, etc. Since it is warm, you should be able to test things, and get them running well now.
Also, consider using non-ethanol gas, which is available at many stations now. It will not deteriorate as quickly over summer. Run what you want in the winter, but at the end of the season use the non-ethanol fuel. Some people run the fuel system dry, but if you do that, I would still do so with non-ethanol gasoline.