Losing coolant

[Silver Surfer]

Hi there. I had a thermostat issue recently. Replaced thermostat, water pump, expansion tank and cap. Flushed radiator. Bled from head and tank screws. Now all seems fine except I keep losing water out from the radiator cap. No exhaust gas in radiator. What else can it be?? 05 TD.

[Redback]

Cap not sealing??

Baz.

[Silver Surfer]

I hoped so but no. Second tank. Third cap. No change.

[Redback]

Coming out the overflow, or past the cap, can you see it coming out.

[Silver Surfer]

It pours out from around the cap. Seen it a few times. Had a rag there other times and soaked it. Poured out on hot days. Otherwise hard to see but losing about 500ml per 100km. I thought it was an issue with the seal of the cap but changed tank and cap and no difference.

[josh.huber]

Has the cap got two rubber seals in it one at the bottoms and one under neath the thread.
If it doesn't its not a recovery cap which means it will let hot wAter out but not suck it back in when it cools

[josh.huber]

Stop filling it up u will notice the level stays n doesn't use any extra

[Tassiefender]

Hi there. I had a thermostat issue recently. Replaced thermostat, water pump, expansion tank and cap. Flushed radiator. Bled from head and tank screws. Now all seems fine except I keep losing water out from the radiator cap. No exhaust gas in radiator. What else can it be?? 05 TD.

Not sure if this could be related, but one day my 05 TDV6 ran out of coolant and of course hit crawl mode with the temp gauge spiking immediately. Checked coolant level - empty. Had only serviced the vehicle two weeks earlier, so topped it up and monitored. Over a tank of fuel, I lost almost all the fluid; but there were never any puddles etc in garage. In the end, I found a very-difficult-to-see hairline split in the plastic housing of expansion tank. At a stand still, it doesn't lose any fluid, but under heat and pressure, it is like a very fine jet spray that evaporates on the radiator or engine components. Therefore, if you don't have puddles of fluid, and you can't find a visible leak, try checking the clear join on the plastic not far from the cap. Hope you find it.

[Silver Surfer]

Thanks everyone. It's going to Bruce Davis next week. I can't work it out. It's definately coming out via the cap. Have tried 3 caps. No change including old one which never leaked. Have tried leaving it. It just runs out of water and starts getting hot. Had to put 2.5L in it. I think either a big air lock somewhere or a head/head gasket issue. Will advise what they find. Cheers.

[Hastykiwi]

Thanks everyone. It's going to Bruce Davis next week. I can't work it out. It's definately coming out via the cap. Have tried 3 caps. No change including old one which never leaked. Have tried leaving it. It just runs out of water and starts getting hot. Had to put 2.5L in it. I think either a big air lock somewhere or a head/head gasket issue. Will advise what they find. Cheers.

May mean nothing, but another scenario. I had the expansion tank replaced, and the original cap was put on this. a couple of months later discovered the cap was not tightening on the tank, like a stripped thread, but not. Just slightly different sizes????? No idea how this came about, but cap had to be replaced.

Other though is bleed screw.

cheers
Nick