As you know, I found a puddle under the MIG last weekend due to rusted coolant pipes...
View from under the car showing rust at welded bracket on coolant pipe
(Just realised looking at this pic, how low my car actually is....check the distance from the garage floor - lower righ hand side of pic - the the bottom of the underside tray...it looks about an inch or slightly more )
Ordered a new set from Sydney for $180 + GST + $28 freight...arrived on Friday.
The first thing I did was spray lanolin/fish oil around the welded brackets on the new set of pipes to give them a little bit mopre protection from rust in the future...
Got it into the cracks and crevases
Then jacked the car up at one side and removed the rear hoses from the pipes to drain the coolant. Squeeze the hose clamps and move them along the hose, then spend some effort getting the hoses off the pipes. They are likely to be stuck to the pipes so move them around a bit to "crack" the seal and pull off. This was the most awkward bit of the whole process.
Draining the coolant...
Romove the front hoses when the coolant has drained using the same method, then clip the zip ties from the pipes which hold the wiring loom to the side of them...
I have air con, so the air con pipe is also zip tied to the other side of the coolant pipes. Snip these off as well.
Then remove the 24 bolts (yes thats right...24 of them) that hold the steel tray under the car. Easy enough, just lots of them!
My tray showed a bit of damage from speed bumps when I took it off...
So I derusted it with acid and sprayed black again to protect it.
Next undo the 3 bolts that hold the coolant pipes in place and remove.
This is the inside of the old pipes...
I applied gasket seal to the ends of the new pipes (if you do this just before you bolt them into place on the car, it helps ease the hoses back onto the new pipes...makes it very easy then seals it tight when it dries).
Bolted the pipes in place, zip tied the wiring loom and air con tubes back to where they were, replaced the steel tray and was all done.
Bled the system using advice from the MG-Rover.org site and all was good until this...
The top sheared off the radiator bleed screw which is made of plastic so I had to remove it and go buy another (cost me $40 in a cab to buy a $3 fitting as the wife had taken her car into town today
I bled the heater nipple which needed to be taken off and poked a bit as it was blocked (a very common thing) before coolant would flow through it.
I tried later to bleed the radiator return pipe but couldnt get anything to come out, even with the car jacked up at the back, so removed the screw, ensured there was plenty of coolant in the header tank and started the engine. This emitted all the air then coolant through the hole...quickly put screw back in and all done!
TIP ON BLEEDING HEATER NIPPLE:
If you don't intend to flush the coolant system, before starting this procedure, make sure the heater is set to the COOLEST setting...ie not on. This traps coolant in the heater pipes. Then when after you refill the coolant AND BEFORE YOU BLEED THE SYSTEM put the heater to HOTTEST setting. This will then allow you to bleed it with less hassle than usual as there should be no air in the heater unit.
It worked well for me. Then a quick drive, cool down and check coolant in header tank and under car for leaks.
OH...time taken - to get hoses off coolant pipes - 1 hour. To stuff about with other bits, paint underbody tray etc - 1 hour. To refit, check everything and bleed - 1 hour. (3hrs total.)