Water loss but no sign of leak

[nik patel]

Whats up guys!

Last 3 months i have been having to top up my coolant probably half a litre every couple of weeks. There is no signs of leaks, rad is fine, hoses seem good, thermostat is fine, not overheathing etc

I need to due a pressure test but before i do that is there anything else i need to look out for?

 

[themanthatcan]

Have you checked under the oil filler cap for mayonnaise? Maybe head gasket failure?

 

[nik patel]

Ye, thats all clean, so thank god

 

[Shy19s]

Anyone is welcome to correct me on my suggestion.. K-Seal.. through the colling system, No harm in making sure theres not a leak, go from there? Unless you've already tryed that?

 

[nik patel]

Where is the K seal?

 

[themanthatcan]

Here:

http://www.kalimex.co.uk/section.html?secpath=01.04.&pgid=17

 

[nik patel]

Has anyone used this? i would have thought its just cloggs up other bits, making the engine run less efficiently?

 

[Jacko4130]

If there was a leak i would rather fix the problem with new parts than stick some goo in the cooling system, might be worth getting it checked out for head gasket problems though.

 

[jojo]

If you can't see the leak, then it could be your waterpump. I replaced mine @50k miles along with the Cambelt, and it had signs of leaking.

 

[Shy19s]

Used to work in an autofactors that stocked K-Seal and sold about 20 bottles of it over a space of 6 months, and every single person said it worked really well. much better than any sort of radweld etc.. its really strong stuff, havnt had any complaints.

If you can't see the leak, then it could be your waterpump. I replaced mine @50k miles along with the Cambelt, and it had signs of leaking

Check your service history, the standard a3 waterpumps are made from plastic that have a tendancy of breaking, you can get a aluminum replacement, this would be the next step after K-seal. This is purely my opinion tho.. no cooling expert..

 

[TheSpaceCowboy]

Or the thermostat? If possible stay away from the Radweld stuff, heard a fair few stories of dread and wouldnt really trust it. I was losing coolant at a fairly steady rate and apparantly turned out to be the thermostat, according to the mechanic.

 

[Shy19s]

thermostat? can someone explain this to me.. i dont get how this could cause u to loose water? .. Especially when your not over heating or running at low temp..

 

[nik patel]

Dont think its the thermostat, as i have changed it and cant see no leaks from there, and car was loosing coolant before i changed it aswell.
I am getting the cambelt done very soon, along with the waterpump, be the cars 2nd one

 

[S3 Dave]

It sounds like you really need to get the pressure test done!!!
If you losing water into the cylinder then you could pressurise the cylinder and fuc*k the lot!! It may be leaking where you can't see on a lighter note!!
I'd make that priority over the cambelt!!

 

[nik patel]

cheers i will get it looked at ASAP, still awaiting Audi to see if they gonna repair the rust on the roof

 

[TheSpaceCowboy]

thermostat? can someone explain this to me.. i dont get how this could cause u to loose water? .. Especially when your not over heating or running at low temp..

I'm not a mechanic but I imagine if the Thermostat housing breaks or cracks then it would leak? Just a guess since I havent done much work on an engine since my 1987 Mk2 Fiesta!

 

[HOUCH]

I would get it pressure tested asap had nightmare with mine recently! Started off with temp gauge not sitting at usual position, stuck in temp sensor no joy fitted thermostat. Gauge sorted few days later low water warning found split in water pipe, replaced pressure tested ok few days later low water light, found split in plastic pipework that temp sensor fits in to replaced, ran engine up really didnt like it overheating blowing water out through top of expansion tank etc.... looked like head gasket to start with, but removed water pump to fine the impeller on back of water pump had broken and fallen off pump, also found tiny hole in small pipe coming from expansion tank very fine mist no drips replaced this also, touch wood no water loss car running fine now.

 

[nik patel]

Cheers i will get a pressure test asap, but been really busy at the moment. The hole in the small pipe of the expansion tank, did you find this when doing the test or just when the engine was on?

 

[HOUCH]

It was after new pump and belt fitted, whilst just running engine up to working temp, can only assume that as the pump was not moving water pressure was building up and found weakest points to leak out from,as had found one split in pipe checked round others.
Hope this helps and hope all goes ok.

 

[nik patel]

I have now found where the water is leaking . Its off the pipe from the temp sensor which comes off an elbow joint. i will get mechanic to look at it when changing the cambelt.

 

[HOUCH]

Cool might be worth getting your guy to remove water pump and either check condition and refit or stick a new one in I think they are only about 30 quid to replace, the pipe you are talking about is the first one that split on mine, not to say that you will have same problem - better safe than sorry.
All the best Houch.

 

[nik patel]

Yes the water pump is def getting changed, any ideas how much the pipe is?

 

[HOUCH]

Is it the one that heads round torwards exhaust manifold-turbo ?

 

[nik patel]

Yes thats the one! my mates brother is an Audi apprentice and hes saying its probably the o ring off the pipe , i wil lget it sorted along with a new cambelt waterpump etc

 

[HOUCH]

Sure it was reasonable doesnt stick in my mind as silly money, deffo give engine bay good inspection above and below (at normal working temp to ensure no other leaks after pump etc fitted.