overheating?

[bully85]

right this is the story so far! my golf started overheating, so i had the thermostat,waterpump replaced to find out the headgasket had gone so after that was repaired thought everthing was sorted for a few days then a hose started leaking so replaced that(also had temp sensor and sender for the gauge replaced)when started it up and gave it a run temp gauge was reading less than quarter of the way up but was still getting seriously hot! then the new temp sender started weeping so tryed to tighten it and it snapped got a new one now the temp gauge goes 3 quarters of the way up and the fan quicks in took it for a short run and the gauge goes right up with the light flashing fan still quicks in and cools it slightly  get home and it doesnt seem that hot when taking the top off the expansion tank!
any ideas would much appriecated and anyone who knows what the two sensors next to and underneath the temp sender are please let me know thanks!

[raferackstraw]

hi mate read the cooling system faq in maintenance section it will tell you how to get air out of the system

basically fill with coolant put heater on full hot with fan full on and allow engine to warm up with the cap on the expansion tank removed . you should see air bubbles coming out of system keep checking lower radiator hose for warmth when it gets hot thermstat is open
once water starts overflowing from expansion tank refit and tighten cap wait for fan to cut in

temp gauge could be dodgy relay see fusebox faq

the other 2 sensors are for ecu and isv for controling idling i think

i found myself that new sensors can vary quite a bit hence the differing reading

also do a search for overheating

[bully85]

just had a close look at fuse box and it seems water has been cumin in the past and it looks rusty etc could this be the problem as the engine doesnt seem to be 2 hot but temp gauge reads full and red light is on ands its been run for a hour like this with no steam etc thanks

[rubjonny]

if it reads full with the light on this is a sign of a short to ground in the temp sensor wire, especially if it does it straight after engine is started cold

[gtigolfthree]

If the wire is shorting to earth the guage will read hot even when engine is cold. To confirm dissconect from sender unit and if guage stays high then a short if it goes to zero then its the sender unit, mabye you are overtightening the sender unit trying to get a seal, use some of that white silicon tape that plumbers use.

[bully85]

if goes 2 zero but its second sender anyidea?

[rubjonny]

sounds like you got a duff one, is it definitly the right rating, the coolant one should have a black collar on it.