Coolant leaking

Charlie Chaplin · October 11, 2023

Hello guys!
My coolant is leaking from tape. Do you know how i repair it? Ex-owner used that and i renewed the tape but when i push the car leaking again.

ltheo · October 11, 2023

Hey Charlie, i just bought an RX400h and after owning it a week i noticed the same thing as yourself but upon further inspection mine was actually a long hairline crack on the left hand side of that pipe you circled, check yours over as could be the main radiator cracked like mine and it looks like its the pipe as its spraying from the crack on to it.

Luckily i am within the 1 month part warranty from the dealer i bought it from so taking it up to them Sunday so they can replace the radiator. Best to replace the radiator probably if its the same as mine.

Greisingel · October 11, 2023

Looks like condenser pipe

Sundance · May 11

I now appear to have this problem. Not sure where the (down)pipe goes but shall investigate. There seems to be a plastic sleeve that looks very insecure. I'm thinking maybe tape it as a temporary measure and limit use of a/c ...

Sundance · May 13

Update FYI. Further investigation finds exactly what Lloyd confirmed last October. The pipe that both Charlie & I highlighted fronts the a/c condenser and doesn't carry coolant. It is in fact a cracked radiator spraying coolant from behind. New radiator needed, as Lloyd found out ... now it's my turn! 😪

Greisingel · May 15

check it isn't water weeping under pressure from the plastic radiator shoulder. If it's that you'll need a replacement – reasonably easy replacement

Sundance · May 17

On 5/15/2024 at 9:32 PM, Greisingel said:

check it isn't water weeping under pressure from the plastic radiator shoulder. If it's that you'll need a replacement – reasonably easy replacement

Thanks Andy, but upon more detailed inspection the crack in the rad is clearly visible ... sadly!

Lydiamight · May 18

Had this problem on my 2007 RX400h--the radiator and the pipes coming from it are plastic.Over the years the plastic becomes more brittle and the constant "flexing" as the engine moves slightly on its mounts causes either the radiator itself, or in my car, where the coolant pipes enter the radiator, to leak. I used a local specialist for the repair. His advice was that he could probably repair the leak with some plastic welding but that was probably not a long term solution. Non OEM radiators were available but I decided to go with a factory original radiator on his advice. The original had lasted for 12 years and a new Lexus radiator will probably see me out.

Sundance · May 18

Same here Ray, appreciate your post, making me feel much better about agreeing to a proper Lexus rad as opposed to EuroCar Parts cheaper lookalikes. I'd like this car to last, it gives such a great ride, quiet, roomy & economical so I too am opting not to cut corners on parts.

Lydiamight · May 18

Hi Rowley--Car has been ultra reliable other than the aforementioned coolant leak, and that was an inconvenience rather than stranding me somewhere. Only other thing was that the original 12 volt Battery did give up after 13 years!

Never failed an MOT and has never even had an advisory in its entire history---this one's a "keeper"

Sundance · May 18

3 hours ago, Lydiamight said:

Hi Rowley--Car has been ultra reliable other than the aforementioned coolant leak, and that was an inconvenience rather than stranding me somewhere. Only other thing was that the original 12 volt battery did give up after 13 years!

Never failed an MOT and has never even had an advisory in its entire history---this one's a "keeper"

That's very impressive Ray. My '07 Lexbus has 12 out of 15 green MoTs, orange advisories on 3 pre-2017, all tyre related. Bought it privately in Dec '22 and am very happy.

Cambelt & water pump replaced at 66k, new 12v Battery @ 71k, now just tipped 89k and I'm wondering about spark plug replacement ... any thoughts?

Greisingel · May 20

This is what happened to me. And the coolant leak manifested itself as liquid around the condenser pipe and the bumper area like Rowley posted Friday

Sundance · May 21

12 hours ago, Greisingel said:

This is what happened to me. And the coolant leak manifested itself as liquid around the condenser pipe and the bumper area like Rowley posted Friday

That's the one Andy, same place, same crack, same result. Being sorted today.

Greisingel · May 21

11 hours ago, Sundance said:

That's the one Andy, same place, same crack, same result. Being sorted today.

It's a classic design fault. The rad replacement was a 2 star easy job. However, I did find that quite a lot of the bolts were absolutely rust melded. Once out I lathered base with high temperature copper grease. Here's to us 20 year old Lexus owners keeping'em going.

Sundance · May 21

By 'eck Andy, if only I was a 20 year old Lexus owner!! 🤭 ... 🙃

Sybaris · May 26

I remember the Enterprise - D had a coolant leak in the warp core.

Didn't end too well.

Charlie Chaplin · June 5

Hi guys,

Itheo was right, there is a hairy crack and after your comments, i realised that there is a chronic problem. i am still using adding 1 lt coolant every month. i am thinking of replacing it with starline radiator which is cheap. do you have any recommendations or experience? Thank you.

GMB · June 5

2 hours ago, Charlie Chaplin said:

there is a hairy crack

Sorry? I beg your pardon?🤔

Boomer54 · June 5

Could always put your finger in it. It worked for the Dutch.

https://www.mikkistelder.com/blog/finger-in-the-dike#:~:text=The Dutch proverb “to put,finger the dike might burst.

Sybaris · June 5

2 hours ago, Boomer54 said:

Could always put your finger in it. It worked for the Dutch.

https://www.mikkistelder.com/blog/finger-in-the-dike#:~:text=The Dutch proverb “to put,finger the dike might burst.

No that was something to do with a dyke.

Boomer54 · June 5

1 hour ago, Sybaris said:

No that was something to do with a dyke.

Hmm, something lost in translation.

Sundance · June 5

12 hours ago, Charlie Chaplin said:

Hi guys,

Itheo was right, there is a hairy crack and after your comments, i realised that there is a chronic problem. i am still using adding 1 lt coolant every month. i am thinking of replacing it with starline radiator which is cheap. do you have any recommendations or experience? Thank you.

Hi Charlie,

I replaced my rad just a few weeks ago with a proper Lexus product having been advised by my mechanic that other 'less expensive' options (eg. starline, even nissens) may not be a proper fit & sometimes have to be adapted, however slightly. There's also the ongoing warranty issue.

Don't forget that old saying "if you buy cheap you buy twice" so if your car's a 'keeper' and worth looking after then I suggest it's also worth the extra spend on a quality rad. Your choice. 😉

Greisingel · June 6

17 hours ago, Sundance said:

Hi Charlie,

I replaced my rad just a few weeks ago with a proper Lexus product having been advised by my mechanic that other 'less expensive' options (eg. starline, even nissens) may not be a proper fit & sometimes have to be adapted, however slightly. There's also the ongoing warranty issue.

Don't forget that old saying "if you buy cheap you buy twice" so if your car's a 'keeper' and worth looking after then I suggest it's also worth the extra spend on a quality rad. Your choice. 😉

Rowley absolutely right – do not skimp. Pay the extra for OEM when it comes to your cooling system

GMB · June 6

18 hours ago, Sundance said:

Itheo was right, there is a hairy crack

Really sorry to hear about the hairy crack, but after studying the photo I can only say that I have certainly seen a few other hairy cracks which are far more interesting than that one.🙀

Boomer54 · June 6

36 minutes ago, GMB said:

Really sorry to hear about the hairy crack, but after studying the photo I can only say that I have certainly seen a few other hairy cracks which are far more interesting than that one.🙀

Gonna report you. Sir , sir , he's being rude !