[srocc]

I have 2012 LX-P 4 cylinder with 34000 miles. What is the recommended change interval for the coolant. Do you just drain the radiator or have it flushed at the dealer? Thanks for the input.

 

[desertrat]

I usually do my own at 5 year intervals. I try to do a complete flush to get all the old stuff out and refill with good quality coolant and distilled water. If you are still under warranty it may be best to use Honda coolant. If you know of a good independent mechanic in your area you might save some money and get a better job than you would from the dealer.

 

[0REDSOX7]

The process itself is pretty easy from what I've read in the service manual. If you bought your car new, the Blue Honda coolant is actually long life and rated for 100k mile so long as any mom and pop shop didn't top it off with some other stuff...

My local dealership charges $150 for a coolant flush, when it would take probably twenty minutes or so do to yourself plus about $30 bucks for the coolant from Honda.

My Accord is at 63K now and at 20% on the MM - as soon as it goes to 15% and tells me what I need to do, it's getting drained and filled again.

 

[srocc]

The process itself is pretty easy from what I've read in the service manual. If you bought your car new, the Blue Honda coolant is actually long life and rated for 100k mile so long as any mom and pop shop didn't top it off with some other stuff...

My local dealership charges $150 for a coolant flush, when it would take probably twenty minutes or so do to yourself plus about $30 bucks for the coolant from Honda.

My Accord is at 63K now and at 20% on the MM - as soon as it goes to 15% and tells me what I need to do, it's getting drained and filled again.

I just found the service manual online. It's showing to change the coolant every 36000 miles. Did they use the 100000 mile coolant in 2012?

 

[0REDSOX7]

Honda doesn't recommend changing the fluid until the maintenance minder tells you to do so - which, is around 100k miles. The blue Honda coolant is the long life coolant. No where on your car's manual should tell you the mileage interval - it's all based on how your drive and what the MM says... Dealers, however, will tell you otherwise...

Now, with that said, it won't hurt to do it earlier than 100K. I'm going to do mine soon at 65K (ish)...

 

[0REDSOX7]

Honda says the new Long Life Coolant Type 2 can be kept for 110K miles/7 years which is what the service manual states is the fluid we have in our cars.

 

[Miker]

I have 2012 LX-P 4 cylinder with 34000 miles. What is the recommended change interval for the coolant. Do you just drain the radiator or have it flushed at the dealer? Thanks for the input.

Measure the coolant with a voltmeter with the negative lead of the voltmeter on the battery (-) terminal and the positive lead of the voltmeter in the coolant while the coolant is at operating temperature.

Best place to check is directly in the radiator at the open cap but I will run the car up to temperature, shut off the engine, allow to cool enough to open cap without scalding myself and restart engine to get back to a decent operating temperature. As long as it's warm it should be OK, just not cold. EDIT: !!!! CAUTION SHOULD ALWAYS BE OBSERVED WHEN OPENING A RADIATOR CAP WHILE HOT !!!!! obligatory caution statement

Do the measurement as above WITH the engine running.

What do you measure ? 0 (zero) volts ? Woo hoo, the coolant is OK.

Greater than 0.300 volts (300 millivolts) and the coolant is worn out. This will allow electrolysis to start and it will eat the metal out of the engine, radiator, etc and cause major damage if left unchecked.

Next check the alkalinity of the coolant using those test strips. Follow the directions and change the coolant if it is acidic. Don't let the coolant to drop below 7.0 ph as then it's getting acidic.

The coolant can act as a current path if the grounds from the engine to the frame and charging system are poorly made or corroded.

Another good reason to at least check the factory connections or do the "Big 3".

Myself, I will change if the voltage reading gets to .150 millivolts (half way to .3, allows me to sleep better at night anyway) What miles or time is that? I really don't remember since it can be different intervals, but the older the engine, car, cooling system is, the more often you might need to change the coolant. Age alone and old, aging ground system may be the reason for the "halflife" of the change interval.

Learned to do this MANY years ago following the discharge of coolant into the passenger floor from the heater core in my 80 Skylark. My fault not changing the coolant but it was my first car, blah, blah excuses, excuses. But it never happened again on any other cars I've owned or took take of. Not even a pinhole caused by corrosion.

For anyone not familiar what electrolytic corrosion can do, check out this thermostat housing. The coolant is literally dissolving the housing due to worn out coolant (roughness on the surface to the right). This is also happening in the engine itself by the coolant passages and around the coolant jacketing the pistons. Guess what happens if left unchecked?

This is not a Honda engine just a representative thermostat housing from a BMW.

 

[0REDSOX7]

Miker - awesome information here. I had no idea this was a way to test it. Thank you for this, for sure!

 

[RickBlaine]

As always, Miker has excellent info and a nice writing style.

I wanted to add that the 7th Gen manual backs up his point. 1st coolant change is at 7 years or 105,000 miles, then 3 years or 36,000 miles thereafter, even though you are still using the Honda "blue" long life coolant.

A radiator drain and fill is all that is required, though some back flush the engine block (I do not). The "old" stuff is not poison, it is just fluid that needs refreshing. After all, you don't drop your oil pan and clean it with every oil change, do you?

 

[Miker]

Miker - awesome information here. I had no idea this was a way to test it. Thank you for this, for sure!

As always, Miker has excellent info and a nice writing style.

I wanted to add that the 7th Gen manual backs up his point. 1st coolant change is at 7 years or 105,000 miles, then 3 years or 36,000 miles thereafter, even though you are still using the Honda "blue" long life coolant.

A radiator drain and fill is all that is required, though some back flush the engine block (I do not). The "old" stuff is not poison, it is just fluid that needs refreshing. After all, you don't drop your oil pan and clean it with every oil change, do you?

You are welcome.

This is something you can also look up on the interwebs but I've been doing this before the interwebs were invented by Al. Learned this from a radiator repair shop when the '80 did it's number on the floor. Always thought that was detrimental to his business since I never required his services again, but he was an older gentleman and had no problem explaining himself or expounding his knowledge. Maybe he just wanted to talk. Thanks to you, wherever you are.

I have also seen mentions of low volts measured (good) but also low ph under 7 (bad) meaning it's changing to acidic. I'd still change the coolant because the acid is really the problem. Dissimilar metals in an acid create the galvanic corrosion. A low voltage may mean the grounds are really, really good.

It's just another tool in the arsenal.