) It was running a bit hotter than normal, but not over heating even at ever so slightly illegal speeds, (just wanted to see what was going on & if it would cool down better if I went faster - honest 
) The Mason was beeping at me (mine is set to go off just before the fans kick in @94 at the top hose, just over halfway between 12 o clock & the end of the scale - Mason modified ) & didn't really stop, until I got down to below 50 on the flat, any load on the engine was setting it off again. I had already found a couple of weeps from the hose connections the week before & thought I'd sorted it, but obviously not
got it home, checked it the next day, no level drop from the night before, no sign of any leaks, so set off back to the softies as I hadn't managed to catch up with every one I wanted to, made it there & back ok, it did feel a bit sluggish & not quite "right", still running a bit hot, didn't seem as bad as the night before. A very kind Northern Bleeder sent me down his pressure test gizmo http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=38823 as I hadn't got around to making one, put it on the header & instantly found two trickles & 3 weeps from hose connections
I've lost count of the number of weeps I've had with the silicon hose connections that seem to have started since the really cold snap, getting fed up with it now (I now know that they should be fitted with constant pressure clamps, not standard - even good quality - jubilee clips.)I was hoping that would have sorted the issues once I gave it a good bleed, (lots of air out) but it was still running a bit hot & still not quite right, I was also just picking up an almost subsonic squeal after 2000rpm
I fitted a digital temp gauge to the top hose to see if it was temp sender issues & it was running in the low 90's which I wasn't very happy with, so I ordered a Mazda stat. While I was waiting for it to get here I was trying to get some temp readings using an IR thermometer jobby, when I realised there were exhaust fumes in the engine bay, had a look around & there was nothing showing on the exhaust manifold, then noticed soot on the turbo & investigation revealed this -
The bolthead had gone completely (found it on the undertray later) & the bottom of the bracket was hanging free allowing this to happen
Stuck a new bolt in, pulled it back into positon & clamped it up again, all cleaned up, along with all the air inlet pipework & anything else that was grungy, all seems to be ok
Mazda stat arrived this morning, so took out he blueprint one (about a year old) pan tested them both, I've got to say the blueprint one seemed to be repeatedly opening a tad earlier than the Mazda one, BUT, it wasn't opening as far as the Mazda stat at boiling point (supposed to be 9.5mm+ at 95 degrees - YOU try getting it to sit at 95 degrees
) but there really didnt seem to be too much in it to be honest. I was hoping for a "Eureka" moment at that point & was a bit disappointed. Fitted the Mazda stat after checking the recirc seat in the top of the stat housing was clean & not worn, took out the temp sender & fan switch & wire brushed the internal bits 'til they were back to bare metal (they weren't too bad though initially) filled it, bled it up really easy, did a quick pressure check & bu66er me, one of the bottom hose connections was weeping again, tried to tighten it up, & the jubilee clamp gave up (I wasn't overtightening - honest), luckily found a spare one, checked it again, found a couple of tiny weeps on the heater hoses, nipped them up, & then it was finally holding pressure, quick bleed to check no air had been introduced, then took it for a test drive.
I wasn't convinced it'd be any better as the stats didn't seem that different in operation, but it was noticably different, it wouldn't go above @ 87degrees on the top hose, it was controlling nicely between 83 & 87 even up Abbotsbury hill which is a nice big 1 in 5, where it had been mason alarming at me a few days before, it was now hovering around the 12 0 clock mark on the temp gauge. It also had lot more "go" thanks to the turbo being sorted
.So if you're running hotter than normal, check for leaks, pressure test the coolant system & I know it's been said before - fit a genuine Mazda stat.
If you're hearing a really high pitched almost subsonic whistle ( I wondered why I had a pack of dogs chasing the bongo) & it isn't the exhaust manifold gasket, have a quick check on that turbo clamp, haven't heard of it going before, but it's not an easy or obvious one to spot.
)
) and a genuine stat.