Cool heater passenger side
 

Hi all , yet another common fault , my zt190 , blowing cool on passenger side , I’ve taken out the matrix and descaled and flushed it out , put it back in and when cars up to temp , both pipes to matrix are red hot , with the heater fan off , so I assume the matrix is clear , but still when heating on , Luke warm on passengers side, is it always a 95% blocked matrix or something else , any help would be great full , as I don’t want anther 4 hours stuffed in the drivers footwell 😂

I'm afraid it will be the matrix, sometimes they get so clogged up you cannot clear them out.

Oh well , more fun times , trying to seal those o ring joints , thanks anyway .

Some years ago when I did mine I wound lots of PTFE tape around the outside of the joint binding it up. It has never lost a drop of coolant since.

Good idea , I didn’t fancy cutting the ends off and using heater tube and jubilee clips , quite yet 👍

It's a truely awful design not fitting of a 75/ZT.

Hi Tony,

With a bit of bodily contortion and cursing you may, in theory, be able to intercept the heater flow and return hoses without having to separate the pipe joints. You can then check that the matrix is free-flowing. I hasten to add that I'm not writing from experience but from the comfort of my keyboard.

One possibility which we ought to eliminate is an airlock. After your descaling and flushing work, did you refill and bleed the cooling system by following the MG Rover procedure for the KV6 exactly? This involves raising the expansion tank when refilling and replacing the bleed screw before starting the engine. You'll find the instructions in full by searching my previous posts.

Simon

You can’t tell if the matrix is free flowing by checking the feed and return pipes Simon, they will still be hot even with a partially blocked matrix.

I didn't say "check" the pipes' temperature Andy, I suggested intercepting them for a flow test ...
Simon :}

Issue with posting is now resolved.