Cleaning Coolant Passages

Whats the best way to clean them out?

 

haha. Boil them out. Barring that, you can scrape them out with brushes or pressure wash the inside of them out to help get all the scale rust and junk out. Might help if it's real bad to knock the freeze plugs or expansion plugs out to give you better access.

but whatever you do, once you break it loose, get it out of there or it'll clog the passages in the radiator.

 

I remember my neighbor who works for well now Navistar then International trucks putting powder laundry degergent into his cooling system and ran the car for a half hour to clean it out. He claimed thats what they did with the big trucks. I by no means think this is a good idea.

 

m38, Do you know any good engine shops around here?

 

engine shops, or machine shops? I use the place out on 258 near rhodestown road. Performance somethingoranother. Perry has done quite a bit for me and it a first rate machinist. Very clean and meticulous and to be honest I think he's very very reasonable.
Don't remember the exact name, but he's right off 258.

 

So, is this in the block or in the heads?

I don't know if a hot tank will remove rust and scale, but I suspect it will. If your shop has a hot tank, ask them if it will clean up the passages.

If not, rust is soluble in oxalic acid. That's what the active ingredient of olde-tyme radiator flush is. You must neutralize following treatment though. Oxalic acid is available as wood bleach.

If this is your heads, you can do it on the bench. Otherwise, put the engine together and flush it. Search the net for "oxalic acid radiator flush" and you'll find lots of advice. Be sure to neutralize if you use acid in any form.

 

Its in the block

 

I was thinking that product CLR (calcium,lime,and rust) might help. With the water pump removed you should be able to follow up with some long bottle type brushes and garden hose flush.

http://www.jelmar.com/CLRbasic.htm

 

I moved my build thread over here from JeepForum. Feel free to take a look. Thanks guys

http://www.earlycj5.com/forums/showthread.php?p=904381#post904381

 

How about muriatic acid and then a thorough washdown of vinegar and then water to neutralize it? Has anybody used it?

 

Muriatic acid is just dilute HCl and should do a very good job on any lime scale. Rinsing with vinegar wouldn't add anything. You would want to rinse with baking soda solution and then water. Rabies infected block

 

Got it. Just repeating something a read a few times online. Thats why I ask the pros around here

 

>>"I remember my neighbor who works for well now Navistar then International trucks putting powder laundry degergent into his cooling system and ran the car for a half hour to clean it out. He claimed thats what they did with the big trucks. I by no means think this is a good idea."<<<

I'm sure it wasn't just laundry detergent,,, The product you should use is "ARM & HAMMER SUPER WASHING SODA" which is sold right next to the laundry detergent,,,,,,, It works great !!! And it is envronmentaly safe,,,, I have been using it for years ,,,,,

 

Yep thats it. Hey I was a kid when I watched him do it and well it might have been nearly 20 years ago.

 

Washing soda is Sodium Carbonate - http://en.wikipedia.org/wiki/Sodium_carbonate

There may be some chemical reaction of the Na2CO3 with the rust and scale.

I suggest the following recipe for effective block and radiator flush. Follow GM TSB 99-06-02-012D on this site and use Wood Bleach for the Oxalic Acid and Washing Soda as a neutralizer.
http://forums.corvetteforum.com/c3-tech-performance/2395596-radiator-cleaner-flush.html

Also, if you get the Prestone "Flush n' Fill" kit with the plastic tee and hose connection, do not leave it in the heater hose. Remove it and install new hose or a brass coupling in the cut hose. These plastic tees get brittle with time (and when exposed to under-hood temperatures?) and will break, dumping all your coolant on the highway.

 

That covetteforum thread is the forscsizzel for cleaning a radiator and block.:tea: