Thread: 1985 County 110 Izuzu Overheating, Help?

Originally Posted by nic_denmark

Morning guys.

So through process of illumination ive got to the heater matrix and bypassed the pipe and isolated it... took for a drive down roads and up the hills it used to get hot on and it was fine!!!!
So is the heater matrix blocked and producing air pockets?
Im going to take it off and apart today but can drive it at least now.

Anyone have a problem with the heater pipes, system?


Also on topic of county- What oil for diffs? and gear box? thought id change oil while im at it.

Much appreciated help by you all.

Hi Nic, can't say I have seen that one before but it is possible I guess. What gearbox does yours have - 4 or 5 speed. The 4 speed requires a light oil 15w40 or 20w50 engine oil in both gearbox and transfer - use the same oil from engine to transfer. For the 5 speed 20w50 or Castrol syntrans and 80w90 or VMX80 in the transfer. For the diffs 80/90 gear oil.

Hi Nic,

The problem might be that the heater is higher than the bleeding bolt on the thermostat.. Mine certainly is. I got around it my making a "T" and installing a bleed valve on it as per the picture below:



If I was to do it again I would just have a bolt and not a valve as the valve leaks a bit and it would be just as easy to loosen off the bolt and wait for the bubbles to stop as it is to press on the valve.

Basically after I've flushed the coolant and bled it once normally I go for a drive with the heater on and stop periodically and tap the valve to see if any bubbles come out. Almost always there are some.

This has the added benefit of making sure your heating is working as well as it can (which was my primary reason to do it - Canberra gets cold!).

Thats a great idea.

I took off the heater matrix and put the garden hose on one end... it flushed out brown for nearly 5 solid minutes...!!!! made a right mess lol.

I then reinstalled it and put new hoses on, i only had time to take for a short run but my heater was 'warm' and it didnt over heat... so im on to it.
Last thing i thought of and last thing i checked was the fault to be the heater matrix, im surprized more people dont have this problem seeing its higher than the expension tank.
But fingers crossed its now on road to recovery, i may however take your advise and install a bleeder to drain any air up that way.

Do you know on top of the matrix what the pull cable does, i know the one on the side closes off the heat flow but the top? (its not a major thing to know for me)

Im chuffed i fixed it without a major bill from a real mechanic.

Thanks all for help and thoughts.!

One of the controls switches the air intake from through the matrix to bypass so you get air in that is only heated by the exhaust in summer. The other one swaps between demister and feet. The third one, which also has the fan switch, adjusts the air quantity, but I can't remember which is which! (This is on the non-factory air)

John