Water loss

[Das boot]

Might be worth checking you aren't losing water vapour via the reservoir cap . I had a similar problem , water level
Dropping slowly and no visible leaks , changed the cap and seal and the level
Stopped falling.

[old onions]

Originally Posted by gramsey438

. 1 bottle of Holts Radweld later and the leak has never come back..

I am a big believer in a product called K-Seal , which is similar and seems to do the job really well . Available from EuroCarParts at about a fiver IIRC.

[Brendan W]

Originally Posted by spudd

Today I left car running for about 20 mins then put on ramps spent an age underneath engine running and no visible leaks. engine must have been running a good 40 mins +. temp gauge in middle and notice water level in header tank had risen from full to the bottom of filler neck. back under bottom hose cold and bottom of rad cold. my thinking thermostat and/or radiator.

Doesn't surprise me for a D5. Had to get in and rev mine a lot to get the stat to open after waiting a lot longer than for a petrol.
Another sneaky leak is the heat exchanger at the back of the sump. What's happening to the oil level?
Level in the reservoir rising could be air trapped. Has the car been for a good run to 'burp' itself since the pump change ?

[spudd]

Originally Posted by Brendan W

Doesn't surprise me for a D5. Had to get in and rev mine a lot to get the stat to open after waiting a lot longer than for a petrol.
Another sneaky leak is the heat exchanger at the back of the sump. What's happening to the oil level?
Level in the reservoir rising could be air trapped. Has the car been for a good run to 'burp' itself since the pump change ?

Been all over the car top abd bottom searching for leaks nothing. the fact radiator and bottom hose made me suspect thermostat. but you never know.

[spudd]

Had only done 26 miles in short journeys since belt change.took it for a 15 mile trug today and level sat bang on max. both hoses and radiator were hot. so hopefully a good burp should have it sorted.

[Brendan W]

Hopefully that's all it was. Keep a weather eye as they say