Changing coolant: best tool/method?

Hi guys,

I'm thinking of buying a vacuum coolant refill tool like this one from Oem tools/Schwaben, please see picture attached.

Here is a link to see it in action: https://www.youtube.com/watch?v=13ekPSv66iI

What do you think of this kind of tool?

From YouTube videos it seems to be really effective and easy to use, but i'm worried about:

- putting too much stress on hoses and potentially causing leaks

- damaging seals by pulling vacuum

Do you see these points as valid or i'm simply getting paranoid?

Do you prefer the classic "burp" method?

Thank you very much!

I can’t speak for that brand, But I work for Lexus and we use a Snap-On vacuum cooling system filler. Never had any issues and saves a lot of time, just don’t exceed pressure rating on the radiator cap or you can crack one of the radiator cores.

Thank you very much Trent!

So the pressure rating on the radiator cap also works for negative pressure (vacuum)!

Your answer was really appreciated :)

Hi Trent, I know this is Off Topic but I wanted to ask you another thing: at Lexus do you also use pressure bleeding tools for bleeding brakes?

I own both a pressure bleeder and a vacuum bleeder.

Just to be clear: for pressure bleeder I mean the tool that attaches to the brake reservoir and by a slight overpressure forces brake fluid out of calipers' bleeding nipple, while for vacuum bleeder I mean the tool that sucks brake fluid out of calipers.

I generally use the vacuum one fo flush the system with new brake fluid.

I would also like to use the pressure one to achieve a better pedal feel and ensuring ALL the air has gone from the braking system. Have you tried a pressure bleeder? If yes, have you ever had problems?

Your experience could be so valuable to me!

Thats actually a good question about how much vacuum the radiator can handle I don’t know if it’s the same it’s just something I do as I’ve cracked an old radiator core in the past from using too much vacuum pressure while bleeding.

I use a snap-on vacuum bleeder for brake bleeding and a fluid hopper on the reservoir to keep it full I don’t pressurise the reservoir. Haven’t had any issues the only cars I do a manual bleed with the brake pedal is on hybrids and LX series because if you vacuum bleed them it leaves air between the brakes and the reservoir as there is a pump in the reservoir

Thank you Trent for sharing your experience.

Out of curiosity, I'm looking for the workshop manual of some cars that require vacuum filling of the coolant to see if they provide a safe negative pressure value

Just a reminder to those with older vehicles, their brake and, possibly, coolant seals were normally single lip designs. This means they were excellent at keeping fluid in under pressure, but may be ineffective at keeping air out under vacuum, especially if a little worn.