good to know - yeah it would only dilute it about 2% or so depending on how much you use. did you add from the radiator cap? did you have to burp the system or was there any overflow, or do you just pour in and close it up and you're good?

 

I added it to the radiator. Just siphoned some coolant out and added the RMI-25.
it is only a few ounces so no real need to burp the system.
After that I would just wait for the stuff to contaminate the overflow then I would empty the overflow and clean it. Then add coolant to the overflow and put it back.
I was surprised at all the debris, thought I possibly had a head gasket failure..... Lol

 

that's what i hear about it - did you have to flush all that out?

im just worried about a mess if i try to add through the radiator.. we'll see

 

I just added it. I removed a bit of coolant and then added the RMI.

 

sorry i meant the crud the rmi25 cleans out of the cooling system

 

When the cars gets hot it will push it out into the overflow. The debris sat on top of the coolant similar to when you have a head gasket failure. I just removed the overflow and emptied it out then cleaned the container and add coolant and put it back.
To my surprise I did this 3-4 times.

 

ohh gotcha. something to look forward to lol

 

Your car doesn't seem to get driven much, I would bet your system is pretty clean and you wont get a whole lot of debris.

 

I thought the same thing, I have driven my car 400 miles in over 18 months and total has under 21k miles. Also, I pulled the head of off the bottom end, both of which had about 1500 miles and that is when I was surprised at the amount of scaling I found. This was 350 miles ago. I then replaced upper and lower hoses and the radiator and cleaned up the water pipe and thermostats housing and replaced the thermostat.
I figured after I flushed all of the old coolant and debris out everything would be fine. Within a month or two and maybe 100 miles the coolant was collecting more debris. I then flushed the whole system again and was amazed to find lots of debris and coolant that was really bad.
I drove another 150 miles and flushed it again and added the RMI-25. When I did this last flush there was more build up and debris. Then using the RMI all the debris started getting flushed out. I forgot about it but then looked at the water pipe when I was out to see my car and noticed the difference of the scaling inside the water pipe. It was obvious to me that the RMI was working.

 

haven't noticed much so far, but i didn't get a ton of this stuff into the system

 

revisiting this - I've put a decent amount of RMI25 into my radiator/overflow tank - I couldn't guess how much, maybe 10 ounces at MOST. do I need to flush the system to prep for winter (RMI25 is water based I believe), or will I be okay here. Temps usually don't dip lower than single digits at the worst, and looks like Zerex at 40% (comes 50%, guessing for the added RMI25) is good to -12F -- a little close for my liking. Anyone ever experience the block cracking from frozen water/coolant mixtures? Or am I just being paranoid?

Car will be in an unheated, detached garage (outside temps will = inside temps) and not driven all winter.

 

Leave the radiator cap off and it'll be fine. -12 is still colder than single digits...

 

^ do people do that in these cases? leave the radiator cap off?

 

It gives some room for expansion. It won't help if you expect it to completely freeze, but it does help if you get some ice build up..


Or, drain a quart of coolant out of the bottom of the radiator and top it up with anti freeze, or whatever product you want to use to lower the freezing point. No reason to do a full flush..

 

thanks for the input - forgive my basic knowledge, shouldn't the overflow tank handle expansion too?

if I drain a quart out and top off a little, do I have to burp the system again?


also, I know we touched on this but just thinking about the summer - deionized water makes more sense than distilled water right?