Heating or lack of (Another thread)

[o0wiz0o]

Hello folks. Bear with me. I have searched the forums but still need some advice please.

My water pump failed and the heater matrix leaked. Both of these have been replaced and the system is water tight. Now the matrix was done first and the heating was fine. Only then did we realize the pump had failed and this was duly replaced.

After the pump was replaced I have noticed the heaters do not give out the usual heat. They are luke warm. Engine gets to temp but the heat is just never there. The Heater matrix feels hot to the touch though. I will get a temp gun on this soon to verify the temp. I do not think there are air locks there. When at a stop the Luke warm air does get cooler.

Much googling has led me to the below possible issues:

- Thermostat (I have one on order)
- Viscous fan stuck on?
- ECU? I found this in another thread - (The aircon fan is controlled by the BCM so if because you have overheated the engine (or the ECU thinks you have) it sets a fault which causes the aircon fan to run constantly with the ignition on).
- The Heater Blenders? Changing these from hot to cold does seem to work though.

Any help much appreciated folks. It's starting to get nippy!

 

[jamesmartin]

if pipes to matrix and matrix or hot then it must be the air control system

 

[o0wiz0o]

Thanks James. The Viscous fan seems ok. The external fan for the AC is not on so am back to the cab again. The pipes in the engine bay to the matrix are hot as is the tiny part of the matrix I can get my mitts to from the side foot well. I'll get my temp gun on it when I get home and see what it hits. I take it am looking for 90 degrees ish? If the matrix is hitting good temps am guessing my Heater Blender is possible not closing fully? If the matrix is not at temp then am back to the thermostat.

 

[o0wiz0o]

Ok. So after a run I got the temp gun out. Both pipes in the bay that go through the bulkhead are 70 degrees. The top pipe on the matrix in the cab is 68. The bottom pipe is 30. To me that does not make sense. Am I right in thinking this is a air block in the matrix?

 

[jamesmartin]

if both pipes going to the matrix are hot you must have a good flow through matrix , a hot matrix wont give hot air in cab unless air can flow through it to the cab

 

[o0wiz0o]

But why would I gain 40 degrees between the matrix outlet pipe and the bulk head pipe in the bay? I would expect similar temps. To measure 30 at the radiator and 70 at the top just seems iffy. I'll bleed it and retest. Thanks.

 

[biketeacherdave]

Can't you just switch on your heated seats like us p38 owners ???? I have my man servant do it for me while the car warms up

 

[jamesmartin]

Can't you just switch on your heated seats like us p38 owners ???? I have my man servant do it for me while the car warms up

quite a few disco owners can

 

[West Slope Rover]

Can't you just switch on your heated seats like us p38 owners ???? I have my man servant do it for me while the car warms up

Then the suspension drops on one side and the door locks start to go up and down and it locks you out. And the only thing left working is the rear wiper, which scratches the window after the blade falls off.

 

[o0wiz0o]

Haha. No no no. My brother tried to tell me his P38 was better than my old Disco but he soon got fed up of all those issues and sold it on. I want as fewer things electric as possible! She's been super reliable. Just needed a little attention this last month. hopefully I'll get this heating fixed and she'll trundle on for a few more years.

 

[biketeacherdave]

Then the suspension drops on one side and the door locks start to go up and down and it locks you out. And the only thing left working is the rear wiper, which scratches the window after the blade falls off.

The perfect description

 

[o0wiz0o]

This is now resolved. Thanks for the input. Looks like the cause may have been the hoses to the heater matrix being the wrong way round.