VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 radiator flush

I have a couple of cooling systems that need to be flushed . Is there something around the home or shop that can be used instead buying from the auto parts ? Thanks

For what it is worth I have heard that dishwasher detergent will work. Never have tried it however. I have soaked the block in a mixture of pure vinegar with about 50% water let it set for several days and was amazed at the gunk that flushed out of there. If you use vinegar you need to do a Arm and Hammer baking soda flush after wards to neutralize the vinegar.

Some of the old repair manuals suggest you use a solution of Lye or Drano (Sodium Hydroxide) a caustic solution, followed by a vinegar flush an acidic solution to neutralize the caustic, then a baking soda to neutralize the followed by a baking soda flush to completely neutralize the acidic solution.

It seemed too strong of a solution (Pun Intended) to the problem for me.

I would try some commercial radiator flush first, (Prestone, etc.) it has worked for me, at least I flushed out a lot of gunk, brown mud rust and the action seemed to produce some beneficial results. At least it made me "feel good" my concrete drive way is still showing the brown rusty stain it left.

The only cleaner that worked for me is the powerded type.Sold under the Prestone name (yellow can) or #7 name (silver can).It's a two ended round cardboard can.Has cleaner in one end and a neutralizer in the other end.Not expensive.Always have a can in the trunk of each car.
Heard that lye will work and the instructions were on the can at one time.I did use it about 55 years ago but thats all I can remember.Would be a no-no to drain it out on most surfaces I would think.

Is the truck engine running yet?

Gene, You must have a supply of NOS Radiator Flush! Where I live you just drain it out and it runs off the concrete, soaks into the ground, makes the grass and weeds grow! If I didn't drain it out where do you think it would go? Ha!

It depends upon the material(s) that contaminate the system. If oil, grease or other similar substances is the contaminant, then the caustic based cleaners or soap, detergent are effective. If more typical cooling system corrosion and hard water solids are the problem then acidic cleaners like vinegar [acetic acid] or oxalic acid [some commercial products] are most effective.

We typically use dilute hydrochloric acid (muratic acid used in swimming pools is the concentrated form). Caution must be used but adding 1 quart of muratic acid to a couple of gallons of water (SLOWLY with stirring) then adding it to a rinsed cooling system, top off with clear water, starting the engine, let run until at operating temperature, let cool, run a couple more times. Drain and dispose of properly. Flush with clear water several times. Adding some of the water to a mixture of one small box of baking soda thoroughly mixed into a gallon of water. If it creates bubbles flush again. Once no more bubbles pour the clear baking soda mixture into the cooling system. Circulate then drain. Rinse with water and immediately fill with 50% antifreeze water mixture or good quality (deionized, distilled, rain water or ?) water with commercial grade corrosion inhibitor (like 18 wheelers use) and circulate.

Ask pushrod if it works? He has done it several times.

Pushrod, probably uses swamp water full strength!