Technical Coolant loss, how quickly is normal?

[spleenharvester]

Hi all, I replaced all the Jubilee clamps with Mikalor W1 heavy duty springband clamps using a WORKPRO hose clamp pliers tool. There are three 38mm clamps required (two for upper radiator hose, one for lower radiator > pipe hose) and four 25mm clamps required (two for the pipe > heater hose, two for the thermostat > heater hose). The two clamps at the back of the engine were an absolute nightmare to get to but we got there (you basically have to hug the engine - locking hose clamp pliers are a must). The two fittings that connect the bleed valve behind the battery are slightly larger, I think about 28mm, but I'd recommend leaving those alone like I did unless you absolutely have to remove them because they are a pain in the ass (you could always just replace the whole pipe if needed but I don't think they are a common leak point). Finally no loss at all on a leak test and I'm confident I won't have to come back to it in a month's time again. Cheers!

 

[ahmett]

To be clear, I lose a bit of coolant over time in very hot weather, 30c+, I think it just evaporates from the heat.

 

[A3jeroen]

That is probably going out of the overflow.
Nothing to be worried about. When I fill to max, I loose a little like your 30 cc. If I leave it between min and max I loose nothing.

gr J

 

[steveras57]

That is probably going out of the overflow.
Nothing to be worried about. When I fill to max, I loose a little like your 30 cc. If I leave it between min and max I loose nothing.

gr J

AGREED you dont get evaporation in a pressure sealed system but if outside temp higher than normal you will get naturally higher expansion!

 

[Piccolo Nero e Bella]

After I had the fluid replaced last service but one, the level took a while to stabilise and I had to top it up slightly now and then but in the last year the level hasn't changed noticeably, sitting in the middle between min and max.

 

[ahmett]

I’ve had 2 coolant related issues in the past 2 years, one broken hose and one broken thermostat so hopefully coolant will stay the same for a while

 

[steveras57]

I’ve had 2 coolant related issues in the past 2 years, one broken hose and one broken thermostat so hopefully coolant will stay the same for a while

Did you replace the thermostat with one with a METAL pipe for the hose to the heater matrix?

 

[ahmett]

Did you replace the thermostat with one with a METAL pipe for the hose to the heater matrix?

No idea ! Just paid someone 160 euros to deal with it and so far so good it’s probably plastic again

 

[steveras57]

No idea ! Just paid someone 160 euros to deal with it and so far so good it’s probably plastic again

It will fail again in the future!

 

[spleenharvester]

lol ours has had I think 6 coolant leaks over the past year. Mostly from the jubilee clamps, but also from the thermostat (the gasket actually degraded rather than the usual plastic fitting). Every time the expansion tank would rapidly fall to the level of the leak. Hopefully the new clamps will put a stop to this nonsense now.

 

[Mercky]

lol ours has had I think 6 coolant leaks over the past year. Mostly from the jubilee clamps, but also from the thermostat (the gasket actually degraded rather than the usual plastic fitting). Every time the expansion tank would rapidly fall to the level of the leak. Hopefully the new clamps will put a stop to this nonsense now.

where is the thermostat in a TA?

 

[z rider]

It's above the oil filter on the side of the engine.

 

[spleenharvester]

This one has a coolant leak again

I did another pressure test, needle didn't move after half an hour but there was a tiny weeny little leak on the one engine-side heater core clamp I didn't replace (my back was absolutely screaming at me at that point in the night so I left it alone!). I'm not sure that explains the amount it's losing (seemingly about 0.5L/month), which makes me think there is either a small leak behind the firewall (which there are no signs of currently) or it's losing it into the engine. Going to replace that clamp and see what happens.

To test for a behind-firewall leak I presume I have to do it with the thermostat open - is there any danger of damaging the heater core with the extra pressure?

 

[varesecrazy]

To test for a behind-firewall leak I presume I have to do it with the thermostat open - is there any danger of damaging the heater core with the extra pressure?

Extra pressure..?

Just go to the figure stated on your Rad Cap

 

[jrkitching]

To test for a behind-firewall leak I presume I have to do it with the thermostat open

No, the thermostat restricts flow, but all parts of the system will pressurise equally. There is also a small bypass in the thermostat.

is there any danger of damaging the heater core with the extra pressure

There is a danger of damaging just about any part of the system if you pressurise it beyond the design pressure (usually you can find this on the rad cap).

 

[steveras57]

Would have though a leek behind the firewall would wet the carpet eventually! also if leaking into the engine you would have coolant in the combustion gases, a simple "sniff test would tell" .

 

[John202020]

Check the radiator when cold on both sides at the bottom? Could easily be a very small leak that's evaporating when hot?

 

[spleenharvester]

So update, I found that my new band clamps were now leaking. I am not sure if the fittings have compressed, if the clamps have stretched or both. So I replaced them all with jubilee clips, bled the system, did the leak test, all OK. Went for a 4 hour drive... it's lost half a liter of coolant again. Did the leak test, no movement after 10 minutes. I am seriously considering part ex'ing the car now because I just cannot get to the bottom of this and I'm starting to think it must be losing it into the engine too somewhere. I have literally spent close to £100 just on coolant the past year.

 

[varesecrazy]

So update, I found that my new band clamps were now leaking. I am not sure if the fittings have compressed, if the clamps have stretched or both. So I replaced them all with jubilee clips, bled the system, did the leak test, all OK. Went for a 4 hour drive... it's lost half a liter of coolant again. Did the leak test, no movement after 10 minutes. I am seriously considering part ex'ing the car now because I just cannot get to the bottom of this and I'm starting to think it must be losing it into the engine too somewhere. I have literally spent close to £100 just on coolant the past year.

Wicked away while driving is virtually impossible to spot..

My 500 loses SOME, but not at your level..

 

[spleenharvester]

Wicked away while driving is virtually impossible to spot..

My 500 loses SOME, but not at your level..

I've since topped it up to MAX and left the car idling for a few hours with the heating full blast and it hasn't dropped at all, so I am hoping it was just a rogue pocket of air that I didn't squeeze out last time. The car at least seems to do OK with the coolant having fallen below MIN, we kept tabs on the engine temp during the journey and it never went above halfway