Just thought I'd share my first experience of finding a bad coolant leak.
I had a large coolant loss on my Audi A4 2.5tdi, which the Mrs drives all the time, coolant was splattered between the timing belt covers and the radiator. I had to top up 2- 3 litres the first time the ‘low coolant’ error came up so a pretty dramatic loss. So I got the car on the drive, removed the timing belt covers to check if it was the water pump, it was all dry as far as I could see and no dripping from underneath that area. The symptoms didn’t fit with a leaking water pump anyway but had to check. So started it up and let it get up to temp to see if I could see any leaks anywhere. I couldn’t see anything at all, the Mrs did a few miles round trip, checked the coolant the next morning, coolant splattered again in the same area but not swimming in coolant and had to put in another couple of litres. I’ve not had to go in depth checking for coolant leaks before so did some research (the web) and decided to purchase a ‘US PRO Tools 19 Piece Coolant System Pressure Tester Kit, 5226’ from eBay for £74. Yesterday I removed the undertray and bumper so I could see all round the radiator etc. So I attached the tester, pumped some pressure into the coolant system and found the leak in a few seconds, link to picture below and is self explanatory. I was initially stood directly in front of the radiator so got soaked a bit before I realised I was stood in front of the leak!
link to pic:
https://1drv.ms/u/s!AmVc9wygjLH0iH_PHeySURtJexBB?e=r3XRgk
I presume just running the car to temp wasn’t a good test for this particular type of leak, it needed to be under pressure so in effect driving the car. Of course when driving the car the coolant was spurting out and hitting the front of the bonnet then mostly disappearing because of the air rushing by leaving just traces/evidence of coolant.
As you can see from the picture, I didn’t need to be Sherlock Holmes to figure out where the leak is, it’s the radiator. So new radiator and condenser fitted, getting the radiator flanges apart wasn't easy as the retaining clips were all rusted in. In the end I cut through the plastic connector pipes on the radiator, removed the rubber hoses and pulled them apart on the bench. They were very tight. Radiator and condenser fitted, lots of corrosion on one of the AC connectors so cleaned up and fitted new O rings, not sure if it will leak but the AC wasn't working before anyway so I might be lucky and just need a regas (I doubt it though) I purchased new 32 mm O rings for the 2 x radiator flanges and 32mm retaining clips as they were rusted to hell. Just waiting for the retaining clips to arrive then connect the hoses up, refill with coolant and pressure test again before I put the bumper back on. Part numbers etc are below for the radiator flange O rings and retaining clips, O rings fit perfect and I assume the retaining clips will be ok as well.
Coolant Pipe O rings 32mm (pack of 2): Febi 29752
Coolant Pipe retaining clips (pack of 10): Febi 31799
I had a large coolant loss on my Audi A4 2.5tdi, which the Mrs drives all the time, coolant was splattered between the timing belt covers and the radiator. I had to top up 2- 3 litres the first time the ‘low coolant’ error came up so a pretty dramatic loss. So I got the car on the drive, removed the timing belt covers to check if it was the water pump, it was all dry as far as I could see and no dripping from underneath that area. The symptoms didn’t fit with a leaking water pump anyway but had to check. So started it up and let it get up to temp to see if I could see any leaks anywhere. I couldn’t see anything at all, the Mrs did a few miles round trip, checked the coolant the next morning, coolant splattered again in the same area but not swimming in coolant and had to put in another couple of litres. I’ve not had to go in depth checking for coolant leaks before so did some research (the web) and decided to purchase a ‘US PRO Tools 19 Piece Coolant System Pressure Tester Kit, 5226’ from eBay for £74. Yesterday I removed the undertray and bumper so I could see all round the radiator etc. So I attached the tester, pumped some pressure into the coolant system and found the leak in a few seconds, link to picture below and is self explanatory. I was initially stood directly in front of the radiator so got soaked a bit before I realised I was stood in front of the leak!
link to pic:
https://1drv.ms/u/s!AmVc9wygjLH0iH_PHeySURtJexBB?e=r3XRgk
I presume just running the car to temp wasn’t a good test for this particular type of leak, it needed to be under pressure so in effect driving the car. Of course when driving the car the coolant was spurting out and hitting the front of the bonnet then mostly disappearing because of the air rushing by leaving just traces/evidence of coolant.
As you can see from the picture, I didn’t need to be Sherlock Holmes to figure out where the leak is, it’s the radiator. So new radiator and condenser fitted, getting the radiator flanges apart wasn't easy as the retaining clips were all rusted in. In the end I cut through the plastic connector pipes on the radiator, removed the rubber hoses and pulled them apart on the bench. They were very tight. Radiator and condenser fitted, lots of corrosion on one of the AC connectors so cleaned up and fitted new O rings, not sure if it will leak but the AC wasn't working before anyway so I might be lucky and just need a regas (I doubt it though) I purchased new 32 mm O rings for the 2 x radiator flanges and 32mm retaining clips as they were rusted to hell. Just waiting for the retaining clips to arrive then connect the hoses up, refill with coolant and pressure test again before I put the bumper back on. Part numbers etc are below for the radiator flange O rings and retaining clips, O rings fit perfect and I assume the retaining clips will be ok as well.
Coolant Pipe O rings 32mm (pack of 2): Febi 29752
Coolant Pipe retaining clips (pack of 10): Febi 31799
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