[Duro5341]

I already ordered Hyundai brand long life coolant (p/n 00232-19010). The bottle says ethylene glycol on the front. Seems similar to pentofrost, although I haven't seen any specs on the oem type. The containers certainly look the same.

The service manual says to flush with distilled water, which is smart where I'm from as the tap water contains a lot of hard minerals. So planning to drain/siphon what I can, refill with distilled, run engine for 20 minutes, drain/siphon and repeat at least 1 more time (till I run out of distilled). After that planning to mix a 60/40 batch to take into account any water remaining in the engine (aiming for a 50/50 mix). Flushing with coolant doesn't sound like a bad idea if you have enough coolant laying around.

Update: Just noticed pentofrost is the same as hyundai oem coolant p/n 00232-19010. Numbers right there on the spec sheet.

You'll be able to see the difference between Hyundai's long life coolant/Pentosin A2 and regular old green coolant (prestone).

The Hyundai coolant and Pentosin A2 are a dark green color (think "hunter green") and can be mixed with each other without problem as they are one in the same. A simple drain and fill is really all that's needed here................

The regular old green coolant (prestone) as some people like to call it back in the day it is a bright neon green color and you must flush out the old OEM long-life coolant for best results as it doesn't mix well with other coolants and must be completely changed every 2 years to prevent cooling system damage as it is NOT a long life coolant.

Duro

 

[gen10-38]

Got around to flushing the coolant for the first time at almost 27k miles (6 years old). It's about a year over the recommended so I did 3 flushes with distilled water to thoroughly rinse it out. After 3 flushes it began draining out mostly clear. At first I was thinking that I needed to put the coupe up on ramps to get the under coweling off but as it turned out I didnt have to. Only the narrow coweling towards the front needed to come off and its easy to reach those bolts with the tires on the ground. With that off i was able to get the catch pan lined up with the drain plug. Id recommend accessing the drain plug from under the car as there is less risk of burning your arm as the engine will be pretty hot during the process... unless you have all day to let it cool down each time you flush. The plug is super easy to get to from under the car. Used a Lisle coolant funnel to fill it up (highly recommended for a clean job). Mixed a 68% batch of coolant... should get me close to a 50% mixed with remaining water in engine. Turned front defroster on while idling to kick the radiator fan on. One last note - I used an air compressor to blow off the radiator while the car cooled down. This made the wait time only 15 minutes before being able to safely open the radiator cap to drain. Use a burly glove just to be safe though.

 

[yyonline]

Hyundai's OEM coolant is made by CCI. Despite being green, it does not use the same chemistry as conventional American green coolant, which uses silicates. Hyundai's coolant is a phosphated coolant similar to coolants used by other Asian makes such as Toyota, Honda, Mazda, Nissan, etc.

 

[focalgencoupe]

Got around to flushing the coolant for the first time at almost 27k miles (6 years old). It's about a year over the recommended so I did 3 flushes with distilled water to thoroughly rinse it out. After 3 flushes it began draining out mostly clear. At first I was thinking that I needed to put the coupe up on ramps to get the under coweling off but as it turned out I didnt have to. Only the narrow coweling towards the front needed to come off and its easy to reach those bolts with the tires on the ground. With that off i was able to get the catch pan lined up with the drain plug. Id recommend accessing the drain plug from under the car as there is less risk of burning your arm as the engine will be pretty hot during the process... unless you have all day to let it cool down each time you flush. The plug is super easy to get to from under the car. Used a Lisle coolant funnel to fill it up (highly recommended for a clean job). Mixed a 68% batch of coolant... should get me close to a 50% mixed with remaining water in engine. Turned front defroster on while idling to kick the radiator fan on. One last note - I used an air compressor to blow off the radiator while the car cooled down. This made the wait time only 15 minutes before being able to safely open the radiator cap to drain. Use a burly glove just to be safe though.

Where did you get the Pentofrost, how much? I think you have to mix it yourself right?

 

[gen10-38]

Not sure about pentofrost bottles but according to the PF part number it is the same as Hyundai Long Life coolant. I found it at hyundaipartsdeal.com (00232-19010) for $14 and change for one gallon, then there is shipping. if available id pick it up from your local Hyundai parts dept to save on shipping. My local dealer didnt have it and didnt want to order it so got it online. You only need one bottle (1 gallon). Yes you will need to mix it with water. And do account for the water already in engine that wont drain, assuming you flush with water. Im thinking only about 1/2 the coolant will drain out. I guesstimated that a 70% concentration will get you close to a 50% concentration once it all mixes together. I still have a little left over (new) coolant which I will keep and use in the coming days as the coolant level settles slightly. Inspect the coolant levels the next few days after replacing it.

 

[gen10-38]

Hyundai's OEM coolant is made by CCI. Despite being green, it does not use the same chemistry as conventional American green coolant, which uses silicates. Hyundai's coolant is a phosphated coolant similar to coolants used by other Asian makes such as Toyota, Honda, Mazda, Nissan, etc.

Seems like a lot of people put cheap green in their coupes. I am not one of them.

 

[Red Raspberry]

I use cheap green good for aluminum engines. No problems in 5 years. Even have a coolant filter that I opened up after a year to find nothing.

 

[gen10-38]

As long as you know what you are putting in and what is required.

To me the easy answer is OEM and be done with it. Less risk, less worry. No need to mix different formulas.

 

[Red Raspberry]

You should do a flush with just distilled water before adding any new antifreeze.

 

[gen10-38]

Technically the service manual says to fill radiator with distilled and the resevoir with half distilled and half coolant.

 

[Red Raspberry]

Technically the service manual says to fill radiator with distilled and the resevoir with half distilled and half coolant.

You will never get all the coolant or water out of the engine. If you fill with 50/50 and start out with water then you will never have 50/50 and always be under. If you don't flush with water then you are leaving old fluid in there.

 

[gen10-38]

Yeah im not sure why the service manual says to fill the resevoir with 50/50 during flush steps. I just filled with distilled and siphoned after each drain.

 

[Duro5341]

I use cheap green good for aluminum engines. No problems in 5 years. Even have a coolant filter that I opened up after a year to find nothing.

This coolant works fine and meets Hyundai's specifications for coolant......................Use it with confidence, but be sure to change every 2 years to ensure long water pump/rad life.

The problem arises when you first install this coolant without first ensuring you have removed ALL OF THE OLD COOLANT. Hyundai's factory fill long-life coolant DOES NOT mix well with standard old green coolant as it's a different chemistry, and it causes brown sludge/staining to start.

Also note that "water wetter" does NOT mix with Hyundai's long-life coolant, but mixes great with standard green coolant.

Just my 2 cents, as long as you fully flush the system before you install the new coolant you'll never have a problem.

Duro

 

[Red Raspberry]

This coolant works fine and meets Hyundai's specifications for coolant......................Use it with confidence, but be sure to change every 2 years to ensure long water pump/rad life.

The problem arises when you first install this coolant without first ensuring you have removed ALL OF THE OLD COOLANT. Hyundai's factory fill long-life coolant DOES NOT mix well with standard old green coolant as it's a different chemistry, and it causes brown sludge/staining to start.

Also note that "water wetter" does NOT mix with Hyundai's long-life coolant, but mixes great with standard green coolant.

Just my 2 cents, as long as you fully flush the system before you install the new coolant you'll never have a problem.

Duro

Read post 31....

 

[Duro5341]

You will never get all the coolant or water out of the engine. If you fill with 50/50 and start out with water then you will never have 50/50 and always be under. If you don't flush with water then you are leaving old fluid in there.

Agreed 100%...............

So when replacing Hyundai's factory fill or their long-life coolant with the same stuff or Pentosin A2, I would recommend you simply drain and fill every 2 years to ensure you always have fresh fluid in there and be done with it.

If you are replacing it with old fashioned green coolant with silicates you have 2 options.............

1) Do 2 sequential drain and fills/bleeding procedures with the new coolant to ensure you have removed/diluted the original coolant enough NOT to cause problems with the new coolant. This coolant is cheap to begin with, and keeping all the mixtures 50/50 takes out the guess work later on.

OR

2) Flush out with distilled water and use a ~60/40 mix to offset the 2 liters of water still in the block that you won't be able to get out.

With this method you are guessing/estimating, and you must check the coolant strength after a week or so and adjust (more water OR more full strength coolant) the mixture to where your happy.

I prefer option 1, as it moves the guess work..................

Duro

 

[gen10-38]

Glad Red mentioned about existing water in block. As adding a 50/50 mix to that is going to put you well below 50% concentration. I don't have any scientific numbers (next time I'd like to measure the amount that drains). It filled my cheapo Walmart drain pan up about half way...guessing a gallon max. I leaned towards a more diluted mix, that's why i just went with ~70% mix when filling. Would rather have it too diluted than too concentrated.

Should also be noted the amount of coolant is different for BK1 3.8 and 2.0:
3.8 - 10.14 Qt
2.0 - 5.81 Qt

 

[gen10-38]

So it's been about 8 months since I flushed my coolant. I'm noticing tiny white spots ALL over each of the rubber hoses where coolant runs through. The spots are highly rounded circles, and not elongated, indicating that the rubber hoses are sweating coolant, as opposed to coolant leaking and getting spread around by the fan. The white spots appear only on the coolant hoses and nowhere else in the engine bay. Any ideas what is going on here? These are the factory original hoses (going on 7 years old). The hoses (aside from the spots) actually appear to be in good condition (no cracking, still pliable, etc). Could too strong of a coolant concentration possibly cause this? I mixed close to a 70% coolant concentration to account for distilled water remaining in the system from the flush. Anyone else have this going on?

Thanks

 

[Red Raspberry]

I would guess the hoses are good for at least 150k miles before needing replaced.

If the hoses are leaking at 15lbs of coolant pressure it will not last much longer. Most hoses nowadays will deteriorate from the inside though.

The coolant concentration should have nothing to do with it.

 

[gen10-38]

It sounds like my coolant system is excessively pressurized. Any ideas what could cause that? Almost daily the gen lets loose ... just trying to keep up with interstate traffic really... so 90 or a buck for about 5 minutes, since these coolant spots appeared. Could something as simple as that cause it? Is this why people get high quality steel braided hoses?

 

[Red Raspberry]

A bad cap but 14 lbs or so is the rating. You only see that above 200F too.