NOT!!!

To follow my window lifter problem (see other thread), I took it into my head to start at the replacement of the thermostat on my 2000 1.6 GLXi which I've long suspected is causing my temperature gauge fluctuations (starts off cold, gets up to running temp, then drifts slowly down to cold, then heats up again at normal rate, heats up quicker when moving slowly or in traffic).

Due to the wonders of the Irish postal system, I still haven't received my GB Haynes manual (nearly 3 weeks now and counting), so I decided to have an old botch at it solo.

Couldn't quite decide on the location of the stat - thought it might be on the RHS of the engine block, under the coolant temp sensor, but couldn't easily get that open. (There was a lot of crusty coolant-coloured stuff built up around that - why? Answers on a postcard...)

Followed some hoses to a thermostat-shaped housing on the front of the block - two bolts, off it comes. Followed by a Niagra of coolant (how much does this engine hold?). No hassle - sure the filling station around the corner sells coolant.

Went to compare the old stat to the new stat (supplied by auto factors). Stat looks similar enough but the seals aren't. Out of a selection of a rubber ring and about four gaskets none seemed to fit. Put in the new stat with the old seal (I know, but needs must). Fastened it back up (mental note - become double jointed if I ever need to open / close the lower bolt again).

Went to filling station(s) all over town - only blue coolant - AAARRRGGGHHHH. Have a feeling I shouldn't mix. Manual says in emergency I can top up with only water. Its an emergency.

Started filling up with water - as I was pumping it through, could hear it bubbling somewhere and sure enough, it was bubbling around the joint. Opened and sealed joint again, this time replacing old stat instead of new one (if the seals are wrong, how do I know the stat is right?). Started filling again. Still bubbling.

Long story short: I'm taking the bus tomorrow. :thumbdwn: And I don't think the wife will be encouraging me to go out doing odd jobs in the evenings for a while either. Surfing the net is safer.

Not everyone is cut out to work on engines

The coolant cyrstalises when it leaks in small amounts, this is the crusty bits around the housing.

Only problem with using the old seal is they expand when you unbolt the housing and thus dont fit back in again.

Smart ***:P I'm normally adequately competent - honest!:confused:

The expansion of the seal would explain the poor seal now - off to the garage to get a new stat and seal.

Edit: BTW - presumably there is only one thermostat in this engine? Is that correct??

Fitted the new seal and stat the other night - both out of a VW garage (also have a Skoda franchise at a different site).

The strangest thing - no matter what I did or how I tightened the two bolts, when I filled the tank with water and squeezed the lower radiator hose, it invariably bubbled out around the thermostat housing.

Now I know for certain that it was fitted in correct orientation with seal in right place, seal fitting, etc. and I tried a variety of tightnesses so I just can't figure it out.

Any ideas anyone?

BTW, I've done around 300 miles since and its been grand - and the temp gauge has sat resolutely on the middle mark all the way, compared to its fluctuations beforehand.