Temperature Overheating

[manko]

Our 56 plated connect gets up into the red on the temp gauge on motorway runs then suddenly drops back to normal and we dont know why.
the coolant reservoir is full to the max limit. If the gauge goes red and we pull over the Coolant Reservoir contents are not even warm as if the coolant isn't going around the system.

Any ideas?

[gt_addict]

Done any work on the coolant system recently? Could be an airlock. If not, could well be a diff thermostat. Easy change but messy.

[paul2012]

Any coolant pipes hot, one to interior heater at back of engine, radiator

If not then suspect water pump...

[phil drew]

does it go to the red if not pushing it on motorway ie around town or sitting at around 50 on motorway

[manko]

Engine fine around town

[manko]

Any coolant pipes hot, one to interior heater at back of engine, radiator

If not then suspect water pump...

Cheers We'll get the pump checked out

[highroof]

Change the sender for the gauge, it's only £13, and it's quite a common problem. Mine was doing more or less the same as yours, changing the sender fixed it.

[f74nk0]

Mine was doing the same I had to change the water pump and it fine now

[phil drew]

mine was doing this and it was blocked flow restrictors in pipes on header tank took them out and drilled them out a bit put back in and fine ever since