Hi everyone, I wanted to clean the cooling system on my d8h and used HCL (hydrochloric acid) 50 litres and 100 litres water. Left it in the system for about 3 hours and flushed it with 600 litres of water mixed with 1.5kg soda ash. What do you think?
That should fix all your corrosion buildup problems - but a solution that strong could create more leaks, as it cleans out pockets of corrosion and scale. I presume you used dilute hydrochloric acid (32%) and not concentrated HCL? Even so, your solution would still have been 16% acid, which is very strong, and which "eats" both corrosion and good metal at the same rate! This is the problem with strong solutions of HCL, it doesn't differentiate between corrosion, scale or good metal! I use citric acid for corrosion removal, it's a lot gentler, and it doesn't attack good metal. I believe you can add inhibitors to HCL to reduce its attack on good metal, but I have never examined in depth what these inhibitors are. However, I have heard that the addition of common household detergent to the HCL solution can reduce the acid attack on the good metal. The detergent also helps release clay particles that are often bound up with rust buildup, and this assists in rust removal.
I would be flushing with a lot more than 600L of water. If you still have water in the system, I'd drain it every time you use it for several cycles, but only if you have rainwater to use, don't do that with hard water. If it's already filled with new ELC, leave it.
Thank you very much for your reply. I used 35% HCL. I didn't use the dozer for over two years with water in the radiator. I thought there could be a lot of rust and scale and used the HCL.
Thank you very much.
There are anti corrosion additives for straight water if you're going to leave water in for a while. Glycol is actually the most corrosive part of antifreeze, water is not bad in comparison. So it's easier to protect against corrosion with straight water.