Flushing the cooling system in a 1941

[Jim Govoni CLC 20546]

Good morning. I am considering flushing the cooling system on my recently purchased 41 Series 63. All original 40K. The hoses and two belts will be replaced and I thought this would be the best time. Does anyone have any experience with Prestone Radiator Flush & Oil Degreaser, or  EVAPO-RUST THERMOCURE ? The capacity of the system is over 25 quarts. They both instruct dilution ratio's as well as how many times to rinse and refill. With that in mind it's an all day job. The water pump is lubricated by a Zerk fitting so I will be replacing the coolant with the usual mixture of anti-freeze I use with all my car + a rust inhibitor. I really just don't want to cause any problems I don't have by flushing a system this old. Thanks for any help.

[gkhashem]

Not an expert on a 1941, but on my 1959s I just drain and fill. My 1959 had some drain plugs in the block to get it fully drained. A 1941 expert should be able to tell you if there are plugs.

I never flush, I usually drain and refill.

Even would consider doing it again next year after driving the car some. Get some fresh coolant in it and then do it again after 500 miles or so. If there is some sort heater core turn in the heat to circulate it there too. I actually run my heat in the summer at times to keep it flowing.

[Bobby B]

The water pump is lubricated by a Zerk fitting......

Make sure you use the correct Water Pump Grease and not too much or you'll blow the seal. Less is more here.......
                                                                     Bobby

[Jim Govoni CLC 20546]

Thanks Bobby, I had to order it from Lubriplate. Yes, less is more my 41 guru already taught me. On a side note I went to fill the oil cups on the generator, the front one was seized shut. With some gentle persuasion I got it open and it was packed shut with hard dried grease/oil. I managed to get that out with a thin scalpel blade. Finally got three drops of oil in front and back for the first time in who knows how long. Thank goodness for shop manuals. 

[Bill Ingler #7799]

Hi Jim: As Bobby pointed out in his reply, careful with greasing the water pump. I do not use an air pump to lube the water pump, I use a manual hand pump.  When using a hand pump and at the first sign of resistance, stop pumping. If you continue pumping after feeling resistance, it can cause you to blow the pump seal.  Bill

[Jim Govoni CLC 20546]

Thanks Bill, that's my plan. I have a very small hand pump I used for the boat, it will be perfect. Thanks for the resistance point. I'll just stop I can always do it again next year.