coolant loss from expansion tank puzzeling

ive now hit a bit of a wall with my disco

got the head gasket and p gasket done by a friend after picking up i drove down the road about 3 miles and the temperature went up normally got to the half way point and just kept going up so i stopped the engine i felt the hoses and the top radiator hose was hot but the expansion was stone cold.. any ideas or had anyone ahd this happen..

so we rebled the system and i was fine and the temprature sat at halfway

and as for today the landy did the same again but after 20 miles journey this time and it was all hot and the expansion tank was boiling and coming out the cap and when i release the cap it just keeps flowing with coolant and i check all the parts and its lost coolant all round as if all the coolant from the whole landrover is being sucked out through the expansion tank

its a 300tdi disco
also the heater is cold as well

Was the system bled properly ? Sounds like an airlock ...

From RAVE (Steps 1 to 3 are draining):

Refit
CAUTION: In order to expel ALL air from the cooling system, follow the procedures carefully.

NOTE: Refill procedure is slow but can be
accelerated by squeezing hoses to assist
removal of air from the system.

4. Add correct mix of coolant into expansion tank until radiator is full (as seen through plug hole on top of radiator). See LUBRICANTS, FLUIDS
AND CAPACITIES, Information, Anti-Freeze
CAUTION: Take care to avoid excess coolant spillage from radiator.

5. Fit radiator plug.

6. Continue adding coolant into expansion tank until coolant appears in thermostat housing.

CAUTION: Take care to avoid excess coolant spillage from thermostat housing.

7. Fit thermostat housing plug.

8. Check coolant in expansion tank is level with indicator post. Add more coolant if necessary.

9. Start engine and run for 5 minutes.

10. Allow engine to cool, check coolant level in expansion tank; top up to level indicator post if necessary.

11. Fit expansion tank filler cap.

glenny117 said:

ive now hit a bit of a wall with my disco

got the head gasket and p gasket done by a friend after picking up i drove down the road about 3 miles and the temperature went up normally got to the half way point and just kept going up so i stopped the engine i felt the hoses and the top radiator hose was hot but the expansion was stone cold.. any ideas or had anyone ahd this happen..

so we rebled the system and i was fine and the temprature sat at halfway

and as for today the landy did the same again but after 20 miles journey this time and it was all hot and the expansion tank was boiling and coming out the cap and when i release the cap it just keeps flowing with coolant and i check all the parts and its lost coolant all round as if all the coolant from the whole landrover is being sucked out through the expansion tank

its a 300tdi disco
also the heater is cold as well

Click to expand...

feel to see if rad gets hot all over the core

There is a slight problem with the Disco, the header tank is lower in relation to the engine on a Disco ...

This is more of a problem on some Discos than others

Raise the expansion tank as high as the hoses will allow, you can tie it up to the bonnet catch, and run the engine till it was warm (without the expansion tank cap on) ... this should bleed the small bore pipe that runs along the inlet manifold ...

You did put the thermostat in the right way round ? didn't you ... i.e with the tiny hole in the flange up...

they arent hard to bleed at all,just remove bungs fill to overflowing job done

Heres how i do it:

Ok start by removing plug from radiator and thermostat housing.

Start filling expansion tank until coolant/water flows from top of radiator, screw this plug back in.

Continue filling through expansion tank until the level in the tank is right then screw the lid on the expansion tank.

Now slowly fill through the hole in the thermostat housing. Once it's full gives the top radiator hose a few squeezes to push any air out then top up and fit plug.

Now start the car for about 10-15 seconds stop it remove the plug from thermostat housing and top up then replace the plug.

Run the car for about 30 seconds and do the same.

Run the car about a minute and do the same.

Now finally run for 5-10 mins and check again.

It should be properly bled now.

At no point open the expansion tank and the top plug at the same time once bled otherwise the water will flow down from the thermostat into the expansion tank.

The other way iv done that works but its not pretty is to fill the radiator full. Fit the plug then fill the expansion tank full, get a friend to blow as hard as possible into the tank- the water will be forced up and out the thermostat housing. As soon as the water appears out the thermostat housing screw the plug in quick then your friend can stop blowing. Job done. Personally I prefer my first method.

Cheers mark

Change the plastic plugs for the metal hot bleed type.

eBay item 221212522209

Before i buy woyld you tell me how they work first please

Have you got hot air at your vents inside?

Could be the thermostat gone as well if its previously been cooked??

glenny117 said:

Before i buy woyld you tell me how they work first please

Click to expand...

Simples.
The plastic bungs are very prone to breaking. Leaving you with a hole in your hot water system. Brass doesn't break so easily. If yu fit the vent plug into the thermostat housing, then you can vent the system without removing the bung and whilst the system is pressurised.

Cheers for that reason i asked is because im not very mechanically minded

Sounds like an airlock to me. Had the same problem on a car of mine I bled it properly and job done. Do you have ramps?? Or a steep hill. Get the engine up high and then bleed. Might help.

DiscoverySi said:

Sounds like an airlock to me. Had the same problem on a car of mine I bled it properly and job done. Do you have ramps?? Or a steep hill. Get the engine up high and then bleed. Might help.

Click to expand...

Will up here do ?

Lmao hahaha