Couple of issues with coolant leak and dipstick problem?

[alpenweiss2]

Hello all

Not been on here for ages. 1.9tdi Wagon 110BHP 1998

I had a problem with the plastic tube that sits on top of the tube where the oil dipstick goes in. Due to age the original one had started to disintegrate. I thought I had found the correct VW part number online (050 103 663) and found a pattern replacement. The part turned up today but it is wrong. It has the part number 049 103 663 on it. The problem is the dipstick will not push all the way in as the top part of the new plastic piece is not deep enough? The dipstick won't fully push in about 10mm is proud.

Can anyone advise?

Secondly I took the plastic engine cover off for easier access and noticed a small pool of coolant on the side of the head/block directly under the black plastic flange that holds the temperature sender. Is it the flange O ring that is likely to have failed. Anyone know the VW part number?

Also how easy difficult is it to replace. It it best to drain the coolant?

Cheers in advance!