Car please!

Hi people,

I would appreciate your help with something. I have a 1998 Civic coupe. I used an antifreeze tester to test the protection level of the coolant before recent outrageously cold weather, but noticed that the reservoir was apparently empty. I was going to fill it with a 50/50 mixture of Prestone ethylene glycol antifreeze and distilled water, but before I went outside to do it I hunted down a copy of the car's manual online (which was a PITA) and was surprised to find it telling me to "Always use Genuine Honda antifreeze/coolant." It also goes on to say:

So I did some searching and read a bunch of threads on here and I'm still uncertain about what to do. It seems like most of the people who insist on the necessity of using the Honda coolant say it's because of the silicates issue, when they give a specific reason at all. The bottle of Prestone I have says "Silicate, phosphate, borate, and nitrite free" as well as "Extended protection to all engine cooling system metals including aluminum".

1) Whereas this Prestone is silicate free, is there any concrete problem with using it? If so, what specific problems will it cause and why?

Even the information in the link in this post, which I guess is supposed to be a memo Honda sent to dealers, says that silicates and borates are the issues.

I would buy some of the Honda coolant and call it a day except for a couple of things:

A) I don't want to accumulate more antifreeze. I'd have to store it in my apartment, which is problematic, or in the car, which is also problematic, because I don't trust the cap to not leak when the bottle isn't upright.

B) I don't know what coolant is in the car right now.

2) If the car already has some ethylene glycol coolant like Prestone in it, could I just fill it up with the Honda blue coolant?

3) How essential is it for the cooling system to be flushed (and how often)? Does it make a difference that the coolant level in the car is low right now? In other words, if I just fill it up with new coolant now, is that good enough?

I live in an apartment and don't have my own driveway, let alone a garage, to DIY anything more than adding fluids. I also can't afford to go to a shop for a flush at the moment if it isn't critical.

Thanks for your help.

kyden

i do it all the time. i always do water pumps with timing belts so not really any issue to me.

Mr. Dabolina

As long as its silicate free you're fine. I've used store brand silicate free green coolant in all of my Hondas with no issues. If I remember correctly, green coolant has a shorter service life than Honda coolant or Dex-cool. So make sure you change it every 3 years or 30k miles.

Also the majority of green coolant is designed to mix safely with all other coolant types (check the bottle though).

When the owners manual was written there was still silicate antifreezes on the market. I honestly haven't seen silicate antifreezes for sale in the couple of years I've been driving.

The issue with the silicates is that they precipitate and act as an abrasive in the coolant system. In an iron engine they're supposed to absorb into the surface layer of the coolant passages and coat the cooling system to prevent corrosion. In an aluminum engine they don't absorb and begin to collect around rubber bits and edges. Consequently causing leakage premature wear.

B serious

iTrader: (1)

The Honda coolant is definiely better for a lot of reasons. But prestone silicate free green stuff is perfectly acceptable.

I buy the pre mix stuff because of convenience.

The only non-oem coolant that I had actual issues with was Peak brand. It silted up the entire cooling system. Had to buy a new radiator and flush out the block out like 3 times.

I am a huge believer in using the OEM coolant...which I buy on Amazon for $20 shipped. But prestone is my 2nd choice.

goldsy

I've been using Prestone for years and have had no issues. Coolant, oil, gas, and washer fluid are the only non OEM fluids in both my Civic and CR-V though.

tony_2018

I'm not sure about leaving it in there for 3 yrs, I think I read on the Prestone 50/50 mix that you flush it every year. Its been awhile and I only use the blue oem stuff cuz it looks cool, its oem, and I know for sure that after 5 yrs I still won't need to flush it.

Mr. Dabolina

Like what? Not being a dick. Just curious why you say that.

B serious

iTrader: (1)

Longer life, better corrision resistance and lubrication for the pump. Keeps the entire cooling system cleaner than aftermarket coolants do. Really good heat capacity. Small differences....but it adds up.

Car please!

Thank you all -- kyden, Mr. Dabolina, B serious, goldsy, tony_2018 -- for your responses, I appreciate it. Sorry I didn't post back sooner. Based on the comments, I ended up filling the reservoir with Prestone, especially since no one specifically answered the question about if it's ok to fill it with Honda coolant if it already has some other coolant in it.

That sounds like a good consideration.


Ok, thanks.


That sounds like a nice advantage for future reference.


I think this is the closest anyone came to answering my question about mixing the Honda blue coolant with whatever is already in the car. I believe the Prestone bottle said it can mix with any other color coolant, but I take that with a grain of salt.

Oh ok, that's interesting.


Ok, thanks.


I think that's what I'll do if I deal with this in the future. In this case I had a bottle that I inherited that I don't know what its story is -- it doesn't say it's premixed, but if I mixed it 50/50 it read weak in a tester. I started with a mix that tested weak and added just enough "straight" antifreeze from the bottle to make it float 5 ***** in the tester. Hopefully that was a reasonable thing to do.


[QUOTE=B serious;49445030]
The Honda coolant is definiely better for a lot of reasons. But prestone silicate free green stuff is perfectly acceptable.


Wow, ok, I'll try to remember to steer clear of that.


I'm a neophyte about this stuff. I didn't even know it was an issue until this came up. But now I know a little bit more for the future.


Ok, thanks.


Like I said, I'm a neophyte and I never really knew much about the service requirements for the cooling system before. I'll have to pay more attention to that in the future. It would be nice to be able to leave the coolant in there for 5 years.

B serious

iTrader: (1)

Just make sure you're using distilled (not "filtered" or "spring" or tap) water if you're mixing your own coolant. You can quickly scale up a cooling system using anything besides distilled water. A lot of drinking water is chlorinated/fluorided a little bit. Chlorine ruins aluminum. Flourine ruins everything. Minerals cause scale and silt. All of the above promote corrosion (the water pump impeller is steel, as well as some other small parts of the cooling system).

Car please!

Thanks for pointing that out. Fortunately I did use distilled water. I'm a little suspicious that someone who had this jug of Prestone before I inherited it may have mixed water into it though, and if that's the case I have no idea what they used. If they were careless enough to do that and then not label the bottle, they may not have been thoughtful enough to use distilled water either.

Just an FYI, I think this is a typo (but I could be wrong). I think you mean fluoride. I think fluorine is a very poisonous chemical. (Who knows, that's probably in our water too though.)

B serious

iTrader: (1)

Flouride is the negative ion of flourine. Flourine is an element, not a chemical.

Flouride is a chemical compound made by mixing flourine with other things. In drinking water, I believe it's sodium flouride.

Car please!

Well clearly you meant to say what you did. I'm certainly no expert on chemistry. I know that water is often fluoridated, but I don't know the chemical details that entails. Does the fluoride damage components directly, or does it break down into fluorine and then that damages stuff?

I don't know if I knew that it's an element, but is an element not a chemical?

Former User

Correct.

It can be both.