[KevinW]

Thanks guys. The engine has run (briefly) - whilst trying to set/check the timing before Christmas resulted in coolant spraying out once some pressure built up. So, I pulled the expansion tank and made a new spacer, as shown in post above, and checked for flatness, and then assembled. All seemed good till I noticed the very slight leak.

Very difficult to see where the drip is coming from as its very slight, but I strongly suspect somewhere near the expansion tank connection. I am guessing will get worse once the car gets up to temperature..... which I'll try to test tomorrow.

So TA-31 is basically RTV Silicone, which i have, maybe it would have been better to use this rather than Blue Hylomar. How much sealant do you use? A thin smear?