Well, I ran the truck last week and afterward I drained the radiator. I had flushed water through it ages ago, but when I drained the water out this time it had a rusty look to it. So, I got to thinking it would be good to flush it out real good with water.

Tell me if there are any problems with this method. I would pull the heater hose at the return side (no heater is attached) and run the engine and continue to feed water to the radiator and let it wash everything out.

Good? Bad? Dangerous? Stupid?


Here is how the engine sits now.

 

I doubt you'll get enough velocity to really flush the block that way. NAPA and other places sell a great cooling system flush, I'd use that, and after running it in the truck a while (per directions) yank the lower radiator hose off (obviously don't want the water to be really hot). Let it cool then flush a couple times with clean water, again pulling the hose so you get a good gush of water to sweep out the crud. If Y-blocks have block drains, open them too. Most of the crud settles at the back of the block, so facing downhill helps.

 

Awesome. Hopefully I can get that done today. Thanks.

 

Get yourself some DAP wood bleach ( oxalic acid, what the old radiator flushes had as the main ingredient) from a hardware store. Mix 1/2 cup with warm water, stir to dissolve crystals. Put into radiator and run. Drain, flush with warm water, then fill radiator with warm water and add a box of A&H Baking Soda. This will neutralize the acid. Flush with warm water after the A&H treatment.

 

Always a good idea to remove the thermostat when cleaning a cooling system.

 

That brings back memories of ''earl''!!

 

Yep, Earl was my inspiration. Here is the video I posted in my build thread of the drive.

Thanks for the tips guys. Napa is 30 miles away, so I will try O'Reilly. Online they say radiator flush is not available. I will buzz over there and see since they are only a mile away. Depending on how that works I might try the bleach method next.