1.8 75 Slow Leak - Help!

[T-Cut]

Originally Posted by Brunty

Could the 2 small & still dripping slowly, puddles be from the plenums as I went through Gold car wash last night.

A plenum check will soon tell you. https://the75andztclub.co.uk/forum/s...d.php?t=125864

On a second note, took oil filler cap off, does hot oil steam? Never noticed it before!

No it doesn't. You may see a faint smoke like fume when the hot engine's running, but not steam/water vapour, especially this time of year. 'Condensation' of combustion vapour may form on cold surfaces in winter, but there shouldn't be any 'steam' as such.

Is there any residual pressure released when you open the coolant cap with the engine stone cold?

TC

[Brunty]

Tipped water both sides, nearside ran straight through, offside sounds like it's filling up, already paid garage to check plenums, had to buy a new set of clips and got Jules plenum guard fitted. Engine left for 3 1/2 hrs to cool down, very slightest hiss, hardly noticeable. No sign off Mayo under cap and oil on dipstick still like new (changed 1,000 miles ago). Drips of water under car are no where near water pump housing, nor rear of engine. Slightly in front of bulkhead and about in line with front chassis sections.

[Brunty]

Took my car for a drive up and down the Welsh Hills with diagnostics on temperature. Likes to sit around 88 -89 uphill to 90 downhill 87. Did not put air conditioning on. Then after about 12 miles, pulled over and let it tick over as if in traffic, watched temp rise slowly to 105, then fan kicked in an dropped it to 88. Gave it a good blast in 4th gear at 60 mph, temp never went above 89. So I know that cooling system is all in good order. It has taken 5 weeks since my son filled coolant to top of fins to lose this water. So wherever it is going, must be an almost impossible to find leak. Coolant level does not seem to have moved since I filled up earlier, checked for over pressure in header tank, only a small hiss after pulling up 1/2 hour ago. At a loss to think where to start. Will be taking Rover for a long drive on Friday, will keep diagnostics on to monitor Temp, put 2 litres of pre mixed OAT antifreeze in the boot in case.
Let you know how it goes.
Thanks T Cut

[Yorkshire GOC]

I think losing 300-400 mls in 5 weeks is worrying - why not take the car to a garage and ask them to do a coolant pressure test on a ramp with the undertray off - i have done this a couple of times and the leak has been spotted? once it was the the IMG (Took nearly an hour to manifest itself ) and secondly loose hose clips near the PRT.