Technical Think my son's matrix is dead.

[JIMBO26]

Hi all. My son's '99 Punto 60S has been a complete pain this winter, with cooling problems sending us round the bend. So far he's had a new thermostat, water pump and cambelt set, cambelt tensioner, and a complete system flush. Worked ok for a week then o'heated again yesterday. Obviously there's a leak somehere, but a look under the bonnet didn't reveal any steam, the garage where he had the work done couldn't find a problem with the HG or a leak either. after using advice from here I bled the system, nice air lock, topped up and went for a ride. After a while I noticed the windows were steaming up so I put on the heater, warm air, nice, no different. Put fan on max and noticed coolant bubbling from the top of the d'board and the cabin filling with mist. Obviously the matrix is boogered, but has anyone had this kind of result before, and is it more than just the matrix that's gone.
Is it ok to run the car with the heater set on cold.

 

[fingers99]

I'm not sure if the Mk1 uses flaps or a heater cock.

If turning the heater off results in no leak, it'll be fine. Otherwise you'll have to either by-pass the heater with a peice of pipe or -- better by far -- replace the matrix.

 

[blu73]

I'm pretty sure its like a cento fingers. so set to cold should be nothing flowing through the matrix - so still be able to use demister but only blowing cold (not much use granted).

Heater matrix is a bugger of a job too, i know of many a fiat that have been scrapped for less tbh. From memory Bushboy has done one recently so can probably advise the best plan of attack, i have never done it in a punto myself.

 

[JIMBO26]

Thanks for the replies guys, I'll check that thread out.

 

[dave]

it has flaps no cock, you could bypass it just to make sure that its the only probem.

 

[Bushboy]

Check out this thread for help on replacing the matrix, including a post and pics from when I did it...

https://www.fiatforum.com/punto/299313-heater-matrix-punto-mrk-1-75-elx.html

It's really not a bad job.. A lengthy one but not a hard one by any means. Just requires upbolting stuff and putting it back together.

Defo worth freeing up a weekend to give it a go although I did it in about 6 hours.