Top hose leaking. Already replaced. Any tips?

BigDaddy · Post by **BigDaddy** » Wed Apr 24, 2024 6:11 pm

Hello everyone. I bought a Gates hose to replace the top hose that goes into the radiator/expansion tank. The problem is where it meets the expansion tank, the metal clip is in but water is leaking out of there anyway when the car gets hot. Is there an easy solution to this? Buying a new hose was supposed to solve this problem!

I have looked and seen the OEM replacement is £85 and this one was £30. Have I just got to bite the bullet?

j3nks79 · Post by **j3nks79** » Wed Apr 24, 2024 6:47 pm

Did it have a new o ring with it?

BigDaddy · Post by **BigDaddy** » Wed Apr 24, 2024 7:39 pm

I’m pretty sure it did. It did seem to be sealing ok but then I have had the cap off a few times recently as have been flushing the cooling system etc and the twisting motion of the cap coming off and on seems to have slightly buggered the seal.

Does anyone have any recommendations for any o ring kits? I don’t know the size of the o ring that’s all but there are some kits on Amazon that contain a few different sizes.

j3nks79 · Post by **j3nks79** » Wed Apr 24, 2024 8:31 pm

I’m pretty sure you can buy it on its own from the Maindealer.
Check real OEM

BigDaddy · Post by **BigDaddy** » Thu Apr 25, 2024 12:21 am

Found the size. 16mm ID x 3mm width. Ordered a pack of 5. Just thought I’d update the thread in case anyone else has the same problem. Hopefully a new one will fix it.

colb · Post by **colb** » Thu Apr 25, 2024 8:05 am

Put some silicon on your finger and run it around the O ring before putting the hose back in so there is no chance of it getting pinched when the hose is slid in. Bit applied to the hose stub also a good idea.

enuff_zed · Post by **enuff_zed** » Thu Apr 25, 2024 8:15 am

Twisting the cap off shouldn’t even touch the pipe?
Are you sure it is pushed completely on? It takes a good push for the last couple of mm.

BigDaddy · Post by **BigDaddy** » Thu Apr 25, 2024 10:39 am

If I twist the cap the expansion tank moves slightly and I can hear pressurised air escape from the small pipe. I don’t know whether the tank is supposed to be completely solid and not move, but mine isn’t.

I’ll try and lube up the ring before I shove it in next time.

enuff_zed · Post by **enuff_zed** » Thu Apr 25, 2024 11:08 am

BigDaddy wrote: ↑Thu Apr 25, 2024 10:39 am If I twist the cap the expansion tank moves slightly and I can hear pressurised air escape from the small pipe. I don’t know whether the tank is supposed to be completely solid and not move, but mine isn’t.

I’ll try and lube up the ring before I shove it in next time.

Ah I see.
But even then it shouldn't unseat the seal.

BigDaddy · Post by **BigDaddy** » Thu Apr 25, 2024 11:26 am

Yeah, I know it shouldn’t. Well I’ll see how the new ring works. One day I’ll get to the bottom of all these niggles I hope!

enuff_zed · Post by **enuff_zed** » Thu Apr 25, 2024 11:34 am

Only other option is if it's a badly made expansion tank. No chance that outlet is damaged is there?

BigDaddy · Post by **BigDaddy** » Thu Apr 25, 2024 4:10 pm

I do have a spare expansion tank if that one is shagged but hopefully it won’t come to that. I’ve just taken a look at it and the large pipe is tight and the smaller one moves a bit. A tiny bit but that’s all it needs I guess.

Will see how it goes. I’ve used so much coolant doing jobs on this car, seems like a lot of jobs involve removing coolant hoses! Ah well, needs must.

Big Bad Boris · Post by **Big Bad Boris** » Thu Apr 25, 2024 6:41 pm

I’ll try and lube up the ring before I shove it in next time.
[/quote]

Sound advice indeed

BigDaddy · Post by **BigDaddy** » Fri May 03, 2024 5:47 pm

Just to finish this thread off I replaced the thermostat today and while doing that took the hose off the expansion tank. There wasn’t an o ring in the small pipe. Whoops! Have now put one in and the connection is much firmer now.

Basically I’m an idiot. But at least it’s sorted now and for pennies.

enuff_zed · Post by **enuff_zed** » Fri May 03, 2024 6:08 pm

BigDaddy wrote: ↑Fri May 03, 2024 5:47 pm Just to finish this thread off I replaced the thermostat today and while doing that took the hose off the expansion tank. There wasn’t an o ring in the small pipe. Whoops! Have now put one in and the connection is much firmer now.

Basically I’m an idiot. But at least it’s sorted now and for pennies.

Good result, and hardly an idiot as you would expect a new pipe to come with one fitted.
A cautionary tale for us all though. I will check every hose I replace from now on.

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