Hi all.

After changing the water pump, radiator, thermostat and top hose, i've got one little coolant leak left. Someone in the past was well aware of these leaks and everything was welded together with K seal or similar. Since i've cleaned it all up, i've obviously exposed another leak.

Seems to be coming from the transmission oil cooler thermostat. The connection with the clip in it just above where the top hose pipe clips on. It's a constant drip like a dripping tap.

I've outlined in red on the picture.

Click image to enlarge

Well I guess nobody knows so I'll answer my own question and hopefully someone in the future might benefit.

There is indeed an O ring in the thermostat housing. Mine appeared to be a little worn and thus coolant was leaking out of the spring clip as illustrated in red in the previous post.

A new thermostat is about £40 but if you have the same leak, you can just replace the o ring with a 20mmx3mm one. Pull the spring clip out keeping your finger in the end of the thermostat as there is a spring inside. Pull out the end from the thermostat and take the o ring off. Might as well take a minute or two to clean any gunk out of the thermostat whilst you're at it. Lubricate the new one and pop it on making sure it's seated evenly all the way round. Stick it all back in the thermostat housing and put the spring clip back in.

Job done.

Click image to enlarge

Click image to enlarge

Click image to enlarge

Click image to enlarge

Click image to enlarge