Club 80-90 Forums

Hi

In May, on route back to the UK, the red temp light started to flicker. I limped home, topping up every time the red temp light came on.

In June my mechanic changed the thermostat + coolant. Not sure if he just removed a hose and drained it, then filled without bleeding. They did not remove the front grill.

The blue header cap + thermostat & fan belt are new (no slack)

Yesterday, the red light began to flicker again.

Checked the top up bottle (behind the flap) and it was normal.

No evidence of any hose leaks.

No coolant mixing with the oil.

Removed the blue header top tank and filled it up and, drove about 30 kms and then the red light came on again.

Checked the plastic top up bottle again and the level was correct.

Removed the small hose leading up to the expansion bottle, thinking it was blocked but it was fine.

Then I checked the header bottle and found it was about half full, so topped it up. Drove home (7 miles) and no red flickering light..

A friend suggested to remove the grill and radiator nut and top up with coolant as he said there may be an air lock.

Could it be an air lock to the radiator?

If so, should i remove the grill and nut and then top up the radiator?

Or, could the problem be elsewhere?

Any advice would be most appreciated.

I’d check your blue cap, then bleed.

Blue cap - remove it. Blow down the spigot, it should make a quacking noise. You should not be able to suck through it, if you can, you need a new one from Brickwerks (other suppliers are available, but with BW you’re getting known quality)

Bleed - (from the wiki)
Bleeding the system on a diesel or GTI engined van is much easier. Fill the system as much as possible, then start the van, raise the revs to about 2K and top up the expansion tank while you have the revs elevated. Put the cap on and gently drive about half a mile. If the temp starts to climb over the mid-point on the gauge stop and re-fill with water. The half mile drive should open the thermostat. Now with the engine running crack off the radiator bleed at the front. Raise the revs to about 2K and allow it to bleed until no further air bubbles come out. Now switch off and top up as necessary on the main expansion tank. If you're suspicious repeat this bleed process again, but it shouldn't be necessary. Wait for everything to cool down and top up the tank behind the number plate