I recently had a motor rebuilt. It was on a dyno with water running through it for cooling. I installed the intake and observed the water jacket on the heads and could see inside the water pump inlet and outlet and noticed a lot of surface rust. Is there any way to get this out before I add the proper coolant?
I’m not gonna lie, I thought about running some evapo-rust through it briefly but thinking it may not be good for gaskets/sealing? I just hate putting fresh coolant in with the visible rust.
I was planning on a 50/50 mix of anti-freeze and distilled water unless anybody has any suggestions? I know there are additives for rust and lubrication also but not familiar with certain brands or effectiveness.
Any thoughts or recommendations?

 

There will be surface rust on any bare metal surface, even interior surfaces of a rebuilt engine. There is no way around it and it is probably negligible, I wouldn't worry about it. If you want to flush it out before putting your coolant mixture in there for good then just use fresh water. As to the mixture and the product there are about as many theories and thoughts on that as there are threads on this site. I recall reading a couple within the last month or two. Look them up for various opinions. I think we even had a few comments by a chemical engineer concerning distilled water etc.

 

Thx for the info and I know what you mean about the theories on distilled H20.

 

I'd just run a coolant system flush through it per the manufacturer's instructions. You can get them at any auto parts store. Then drain the coolant and add the antifreeze/distilled water solution.

 

I flush with dehumidifier water and fill with distilled. I also put concentrate in first on final fill because it's undetermined how much you can exactly get in there. Then I add distilled over the next few runs.

 

^^^THIS. I've had really good results with the Radiator Flush from Rust911.

 

Just had great results with CRC ThermoCure. It's made by the makers of EvapoRust.

Good luck!!!

 

Thanks for the recommendations fellas

 

I have never had a problem with 50/50 mixture of coolant/anti-freeze and distilled water. I never really had a problem using tap water either.

 

If your Olds is always parked in a garage you won't have a problem with 50/50 mix. But if you live up north or park outside make sure you prepare for those cold winter temps.

 

There's been some discussion on AACA recently about a product called No-Rosion. People who have used it like it but the way I'm reading them they're using it with straight water coolant.

50/50 has always gotten me -30 to -35 degree freeze points. That's plenty good for this area. I've actually checked SG on that mix and both a hydrometer and a refractometer have verified the floating ***** type tester. Always wanted a refractometer of my very own. Since retiring I no longer have access to one.☹

 

good stuff, thx