poss heater matrix??

[dan_vtec]

a few days ago i got the car out of the garage as i thought id use it while the weather was nice and there was a pool of water and antifreeze in footwells. i started the car and drove it to my work premises and its was dripping out, at work i bypassed the heater pipes under the bonnet and took the car home again, havnt had time to investigate yet but im guessing its the matrix and not a pipe or something, anyone know where i could get a replacement? 1990 mg maestro 2.0 efi.
thanks

[countrydude]

It could be many things but worst case scenario is too much pressure in the cooling system: HGF!

[MaestroTurbo]

On a 2 litre petrol its very unlikely to be HGF, much more possible is the pipes leading to the heater matrix corrode and its leaking from there. Diesels suffer more from excess pressure in the coolant system because the compression is much higher and so are cylinder pressures, so when it goes due to corrosion of the HG near the water gallery, combustion pressure goes straight into the coolant system causing a cold heater and water blowing out the header tank.

[dan_vtec]

hopefully its just the pipes cooroded, but knowing my luck it will be matrix, whats easiest way to access to have a look? is it a dash out job? or can it be done another way? i was thinking try remove glovebox and also any under trays from bottom of dash and see what i can see.

[E_T_V]

Dash out job if it is the matrix, however if it is the pipes then you can change these in situ. Check the flange joint between the pipes and the matrix as the gasket can fail leading to leaks if the pipes aren't leaking themselves.

Taking the dash out is pretty easy compared to most cars so don't fear if you do need to remove it.

[dan_vtec]

Dash out job if it is the matrix, however if it is the pipes then you can change these in situ. Check the flange joint between the pipes and the matrix as the gasket can fail leading to leaks if the pipes aren't leaking themselves.

Taking the dash out is pretty easy compared to most cars so don't fear if you do need to remove it.

good stuff, will have a look tommorow if i get chance, fingers crossed not the matrix.

[fatboy.01]

the old boy at work (ex rover mehanic) tould me the matrix can be changed by removing a riveted bar from the dash somewere

i dont know what mk maestro but im sure he's telling the truth

[oseerees]

easy to check.

Seat right back reclined, lie on your back:eek:, head in floorwell, torch, look up, feel and check, simple!

Bet you it's one of the steel pipes or where it fits to the matrix.

9/10 it won't be the matrix itself, but matrix does tend to clog - back flush it out with a hose from engine compartment once pipes sorted.

IF unlikely it is matrix, get new one off Buypartsby online - best price.

[Jumturbo]

It is more than likely corroded pipes. Unfortunately they are made of steel and rust from the inside. I had to change them on my white monty, luckily Rover were still trading and the part was easy to get hold of. Quite easy to change too, but make sure you drain the system first! The hardest bit is undoing the fiddly screws or bolts that clamp the flange of the pipes to the heater. Could be the gasket too. If the pipes aren't too badly corroded, you could take a chance and use one of these proprietry plumbing 'stop leak' compounds or wraps on the outside. My pipes only had a tiny pin hole but would have got worse, so at the time decided to change them as availability wasn't an issue. ;)

[Simon]

Tighten up the 3 allen headed bolts that clamp the pipe flange to the matrix - I bet they have come partially undone. There were 2 types of "gasket": a rubber gasket type thing the same shape as the pipe flange, or O rings.

[dan_vtec]

havnt had time to look yet been busy as hell this week. the heater is bypassed at the min so it aint leeking just means you got a cold ride haha.

[BIGLAD]

havnt had time to look yet been busy as hell this week. the heater is bypassed at the min so it aint leeking just means you got a cold ride haha.

When you have had time to check, I have a good used/2nd hand matrix and am 99% sure I have some of the "O" rings (New).

[dan_vtec]

When you have had time to check, I have a good used/2nd hand matrix and am 99% sure I have some of the "O" rings (New).

havnt had time to check as yet, pm me a price though.

cheers

[BIGLAD]

havnt had time to check as yet, pm me a price though.

cheers

PM Sent and I have plenty of the "O" rings

[maestro vans]

In the past I have found on a number of the vans you get pinhole leaks, usually these are below the rust bubbles on the outside of the pipe. If you can remove the pipes and wire brush or sand a clean patch around the hole which is usually easy to spot. Get some plumbing flux solder and gas burner and patch the holes with solder. Has worked fine for me in the past.
Good luck

maestro vans