How often drain & replace coolant?

[paulri]

My Civic manual says every 30K; I looked on my spreadsheet and receipts, and it hasn't been done in at least that long. I couldn't find any reference to that work done (owned it since 80K).

I peeked under the radiator cap, and the fluid was a dark green (I filled it up with OEM Honda once or twice in the last several months). No crusty dirt or grime at all.

OK--so should I be doing this every 30K like the manual says?

 

[CapitalTruck]

Why not? The civic probably even has a petcock on the radiator, unlike my GM vehicles that require removing lower radiator hose. That was the standard change interval for regular ethylene glycol antifreeze for a long time until the long-life coolants came out. I would follow the interval in the manual. With Dex-Cool I do mine about every 75k. I will never let antifreeze stay in a car for 150k.

 

[gregk24]

I change the Accord's every 3 years with Honda Blue II long life.

 

[Ihatetochangeoil]

I too, keep a spreadsheet and track of most everything done to my cars; even if it is just new wiper blades. I do not flush or change my coolant based upon mileage or time. I use ph test strips available on Ebay or Amazon. You can do whatever lets you sleep at night and I'll do my thing. Peace.

http://www.ebay.com/itm/AquaChek-Cool-Trak-311519-Coolant-pH-Boilpoint-Freezepoint-Test-Strips-50-Pack-/351640965907?hash=item51df6f5313:g:kV0AAOSwpzdWqkWl&vxp=mtr

 

[CapitalTruck]

I also have regularly used test strips. I didn't want to get into all of that, I didn't know if the OP would be into it. pH strips are probably the best way to gauge coolant life.

 

[zzyzzx]

You really only need to change out coolant once in a cars lifetime, when the car is a few years old. After that, you will be replacing cooling system components often enough to keep the coolant new. By this I mean you really only have to go out of your way to do a coolant change once in a car lifetime, and after that it will be part of some other procedure.

 

[paulri]

Originally Posted By: zzyzzx
You really only need to change out coolant once in a cars lifetime, when the car is a few years old. After that, you will be replacing cooling system components often enough to keep the coolant new. By this I mean you really only have to go out of your way to do a coolant change once in a car lifetime, and after that it will be part of some other procedure.


What procedure? I don't think I've changed the radiator since I bought it at 80K. Or is it considered part of a larger job, like a tune up?

 

[Kira]

"...after that it will be part of some other procedure.". I like that approach but it is incomplete and doesn't allow for scheduling.

I will be changing a coolant temperature sensor later today and I will bleed off some coolant and replace with fresh "just because".

I will log it as a replacement part and a radiator drain & fill.

 

[doublebase]

It depends on what year your vehicle is and the type of coolant it requires. Sounds like you have an older Civic that uses the older green coolant (inorganic acid technology). Green coolant needs to be changed every 30 k miles or two years because the additives break down and corrosion can result.

If you have a newer Civic you should be using Honda Blue long life coolant or an equivalent. I believe that coolant is an Oragnic acid technology formula in which the additives last much longer and the coolant is easier on water pumps seals. The older green style used silicates which can be abrasive to engine internals/seals/etc.

The blue Honda coolant can last up to 100,000 miles on original fill...I believe it's 50,000 miles on the exchange.

A lifetime ago there was only "green" coolant, you can thank Ford for changing all that. Years ago they discovered that their fleet vehicles in Europe were having a hard time handling the tap water over there because it was high in minerals, salts, metals, etc. They developed these formulas that were less abrasive to the cooling system....I will say that on all the fords I've worked on over the years, their cooling systems are pretty trouble free compared to other companies (at least they were 10-12 years ago, don't know how they are now).

There are other formulas out there...HOAT hybrid organic acid technology (in fact Honda blue may be that, I'm not sure). Be either way most newer factory coolants are long life coolants. You can convert your civic to the Blue formula, but you have to make certain that you remove ALL of the OLD STUFF. ALL OF IT. If not the coolants will mix and neither additive package will do what it's supposed to do, I've also seen IAT coolant turn into a gell like substance when mixed with OAT coolant and clog radiators and heater cores.

 

[Ihatetochangeoil]

Not necessarily. I bought a clear plastic 16 quart rectangular salad bowl from a restaurant supply at a flea market for $5. It hangs on the wall in my garage, and it is large enough of a surface area opening that I can place it under a vehicle before doing something really messy like yanking the lower radiator hose and I catch 90% + of my coolant and reuse it when doing something that requires the cooling system to be drained.

If the used coolant is reasonably clean and has good pH, why replace it with new just because you have to drain it? It's not just the money spent on new coolant and distilled water (which is REALLY cheap), it's the hassle of remeasuring and maintaining the 60/40 mixture that I prefer to run. And I guess it's probably better for the environment (like I care).

 

[Merkava_4]

I drain and fill once every year with dex-cool and distilled water.

 

[WobblyElvis]

Originally Posted By: zzyzzx
You really only need to change out coolant once in a cars lifetime, when the car is a few years old. After that, you will be replacing cooling system components often enough to keep the coolant new. By this I mean you really only have to go out of your way to do a coolant change once in a car lifetime, and after that it will be part of some other procedure.


This is an interesting way of looking at it and I would have to agree. I don't know what they have changed in cars in the last 20 years but the coolant seems to last forever. If I am sure of the car's maintenance history, I wouldn't change coolant in under 6 years/75,000 miles. Keep the system clean and don't mix coolants.

 

[JMJNet]

There are a lot of procedure that needs coolant refill like changing coolant hoses and passages (there are a lot of small hoses along the way), changing water pump (usually with timing belt at least in Toyota), changing radiator.

If you are in doubt, just change the coolant already.

After that, then you can decide if you want to do every 30K or it will be part of other procedure of fixing the car.

If that is a 98 Civic, I used to have a 97.
The radiator is small and very easy to change.
Actually, it is an easy car to work on.
It was a great car.

 

[paulri]

I see that both Prestone Prime and Valvoline Zerex Asian car, have a 5 yr/150K mile recommendation.

There's no way I'll go 150K in 5 years. If I were to change to one of those fluids, would it be best to change it at 5 years? These cars will probably be between 40 and 55K by that point. Or could I go longer?

 

[barkingspider]

For old school green coolant, I would replace approx every 2 years. Dexcool or long life, every 4-5 years. This is if the vehicle cooling system is normal and not leaking.

 

[nwjones18]

Originally Posted By: WobblyElvis
Originally Posted By: zzyzzx
You really only need to change out coolant once in a cars lifetime, when the car is a few years old. After that, you will be replacing cooling system components often enough to keep the coolant new. By this I mean you really only have to go out of your way to do a coolant change once in a car lifetime, and after that it will be part of some other procedure.


This is an interesting way of looking at it and I would have to agree. I don't know what they have changed in cars in the last 20 years but the coolant seems to last forever. If I am sure of the car's maintenance history, I wouldn't change coolant in under 6 years/75,000 miles. Keep the system clean and don't mix coolants.


I agree as well..

 

[JustinH]

We dumped the coolant at 75k in a Toyota Matrix, because I was replacing hoses.

Used the Zerex for Asian Cars, approved for use in Toyota.

Old coolant came out looking fine.

New stuff went in, same color as the old stuff, pink.

Coolant quality must have improved over the green stuff.

 

[paulri]

Time to bash my head against the wall.

Thought I was being good by topping off my Civic coolant. Yes, the coolant in the radiator is a nice fluorescent green. But my jug of Honda coolant (I emptied a quart of it into the reservoir, to bring it to the full mark) is blue. Reservoir IIRC was empty when I poured it in.

This blue is the new type 2 Genuine Honda coolant--it is also 5 yrs, but only 60K miles.

Well, I was going to drain it all out, anyways. Hopefully mixing didn't goof anything up.

So if I need to drain it NLT 5 years, regardless, I'll just stick with the OEM blue, unless the price difference is big enough for me. I'll check on all this tomorrow.

 

[mclasser]

My Hondas see their first coolant change at 7-8 yrs with the TB & water pump. My Accord's had 2 changes in the 14 yrs we've had it. My I35 has Peak LL in it which can supposedly go 5 yrs but I'll be draining it around 4.

 

[Bgallagher]

Originally Posted By: barkingspider
For old school green coolant, I would replace approx every 2 years. Dexcool or long life, every 4-5 years. This is if the vehicle cooling system is normal and not leaking.


+1 This is what I do with my vehicles