Coolant leak- I'm flummoxed

bigwinn · Post by **bigwinn** » Tue May 23, 2023 7:18 pm

Evening all

Asking for advice as I am running out of options here.

53 2.5 manual- Ians car! Which is a stunner by the way!

I'll cover off whats replaced:

Expansion tank
upper hose
lower hose
heater to expansion hose
block to expansion hose
water pump

I cant get the fault to appear... so I drive it for a decent distance, no issues with overheating etc. When I observe the car underneath- no signs of leakage at all. I then let it cool and same- no sign of water loss or coolant leak

However- when back in Ians garage there is definite coolant leak (colour and feel say its coolant not brake, AC etc)

Whats really weird is that the leak ONLY shows itself at the back of the drivers side wheel; dripping around the rear wishbone and pools around the drivers wheel

I'm open to suggestions and nothings off the table

Thoughts?

Stuart

j3nks79 · Post by **j3nks79** » Tue May 23, 2023 7:22 pm

Have your tried to pressure test the cooling system?
That will expose any weak points.

bigwinn · Post by **bigwinn** » Tue May 23, 2023 7:24 pm

not yet that may be the next option

j3nks79 · Post by **j3nks79** » Tue May 23, 2023 7:28 pm

It will be the only real way of testing the system without chucking parts at it.
Cheap kits on eBay for around £50-£60

colb · Post by **colb** » Tue May 23, 2023 7:55 pm

If the leak is definately coolant by its colour and taste (sweet) then pressure test will be the way to spot any small leak. If it was clear water could it be aircon condensation dropping off when switched off and in the garage?

bigwinn · Post by **bigwinn** » Tue May 23, 2023 7:58 pm

colb wrote: ↑Tue May 23, 2023 7:55 pm If the leak is definately coolant by its colour and taste (sweet) then pressure test will be the way to spot any small leak. If it was clear water could it be aircon condensation dropping off when switched off and in the garage?

yeah thats what I was thinking re aircon run off

bigwinn · Post by **bigwinn** » Tue May 23, 2023 7:58 pm

the only 'issue' i have is that surely the system is up to pressure all the times I've had it run up to temp??

colb · Post by **colb** » Tue May 23, 2023 8:15 pm

How about a partial blocked scuttle drain on the right hand side that may find itself down where you spot the leakage dripping by the drivers front wheel.

bigwinn · Post by **bigwinn** » Tue May 23, 2023 8:25 pm

All drains cleared by my fair hand and checked

j3nks79 · Post by **j3nks79** » Tue May 23, 2023 8:30 pm

colb wrote: ↑Tue May 23, 2023 7:55 pm If the leak is definately coolant by its colour and taste (sweet) then pressure test will be the way to spot any small leak. If it was clear water could it be aircon condensation dropping off when switched off and in the garage?

Easy to rule out by running it without the aircon being on and see if it still happen

Zedebee · Post by **Zedebee** » Tue May 23, 2023 9:09 pm

Could it be washer fluid coming out of the bottom of the washer reservoir and dripping off the undertray?

bigwinn · Post by **bigwinn** » Tue May 23, 2023 9:22 pm

Zedebee wrote: ↑Tue May 23, 2023 9:09 pm Could it be washer fluid coming out of the bottom of the washer reservoir and dripping off the undertray?

Thankfully the washer fluid is very blue... and its not blue!

same logic applied to aircon which is usually green!

j3nks79 · Post by **j3nks79** » Tue May 23, 2023 9:25 pm

bigwinn wrote: ↑Tue May 23, 2023 9:22 pm
Zedebee wrote: ↑Tue May 23, 2023 9:09 pm Could it be washer fluid coming out of the bottom of the washer reservoir and dripping off the undertray?
Thankfully the washer fluid is very blue... and its not blue!

same logic applied to aircon which is usually green!

Its condensation that drips from the AC compressor and pipes etc. wouldn’t be green bud. It just water

Pondrew · Post by **Pondrew** » Tue May 23, 2023 10:07 pm

bigwinn wrote: ↑Tue May 23, 2023 7:58 pm yeah thats what I was thinking re aircon run off

Unlikely to be the a/c in the weather we have had recently. Needs to be pretty humid and very warm to create the amount of condensate you are talking of.

patriot66 · Post by **patriot66** » Wed May 24, 2023 12:11 am

Hi Stuart. Have you checked the o-ring on the temperature sensor in the bottom hose. They can weep and drip down, perhaps running along undertray and onto ground by the wheel ?

Si

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