Ok, I think it's time to start saving for a new car and run this one into the ground then use it for spares.
1997 TF Altera, 5-speed 252,000k.
I've done heaps of mods to it but the problems seem to be continual lately.

LPG problems that can't be diagnosed or fixed.

Erratic idle issues (granted these haven't happened since a full TB and ISC clean a few weeks ago)

Broken front engine mount.

Middle Exhaust starting to rust.

Coolant stench in the cabin since the HC leaked.

And now, to top it all off I have brown sandy coloured sludge in my radiator 1/8 tsp worth on cap.
Engine oil still looks fine and the coolant level hasn't dropped so not sure if it's just due to cheap coolant or a dying head gasket.
I might try getting a power flush done.

Time to retire the old girl and donate some of her organs.

To be honest, most of what you have listed is

a/ not hard to fix and
b/ could have been prevented by better maintenance

Either way, if the heater is now fixed, remove and wash the carpet, if the coolant was cheap nasty coolant, replace with Nulon or similar

If the body and general condition of the car is ok would be a real shame to scrap it

To be honest, most of what you have listed is

a/ not hard to fix and
b/ could have been prevented by better maintenance

Either way, if the heater is now fixed, remove and wash the carpet, if the coolant was cheap nasty coolant, replace with Nulon or similar

If the body and general condition of the car is ok would be a real shame to scrap it

Is Super Cheap Auto coolant considered cheap and nasty?
The body is ok apart from the crows feet on the rear quater.
I try to maintain it really well but unfortunately I've made a few mistakes (cheap coolant, not cleaning TB regularily)
I guess after all the issues with the LPG (which still isn't fixed and two LPG specialists can't work it out) I'm a bit over it, in trying to fix the LPG issues I've changed spark plugs x2, leads, dizzy cap/rotor, o2 sensor twice (universal first then genuine) and spent a couple hundred on labour.
I'll fix the few little issues and hopefully that will be that, I'll just stop telling my wife lol
I'm just going to use LPG for highway driving where it's most useful and petrol around town to avoid the driveability issues.
I'm still trying to find a place that can supply the parnell stepper motor, even places in the UK don't have them.

Hi Mal, should I use the green Nulon stuff or the Red stuff?
Also, last time I changed coolant I just drained then filled, would it pay this time to put in some Nulon radiator cleaner, drain and fill with distilled water, run for another 20 min or so, drain then fill?
I'm inclined to do this before driving 4,000k

Your best bet is if you can remove the 2 block drains, they are 14mm bungs, little hard to get to but on the front if you look down and follow the dipstick tube down the block you will see the 14mm head of the bung sticking out of the block, the other one on the back is about the same distance in from the other side of the engine

With these out, give a good flush, you can just hose water in from the top of the radiator, if you want to you can do the above with flush, and then once cool enough not to burn yourself remove the bungs and flush then

Any tips for getting to the rear bung? I slashed my hand up and couldn't get to it last time (which may be what's caused the corrosion, I drained radiator and removed front bung, filled and ran, waited for it to cool and did it again) so I guess I mixed two coolants :(
Our water here is heavily clorinated (comes out in your sweat) so I'd prefer not to use tap water.

Wow, what a p****K it is to get that rear bung out, even harder finding the hole to put it back in, I had to come in and look at the manual to find it.
There must have been some sludge built up on the rear bank because I had to do a high pressure flush (plugged radiator and front bank), nothing came out then water exploded all over the firewall, that sandy sludge crap was all over the bung.
besides that the coolant wasn't brown and just had some white flecs like dandruff it it (1 flec to 100ml).
I am slightly concerned that I only managed to put around 8.5 litres back in (I drained via the radiator, overflow bottle and the two engine bungs).
I let it run for about 15 minutes until the hoses got hot and topped off after the initial fill and got maybe a litre into the radiator
Will check it again when the engine cools down.

How do I get the air out of the hoses?

Wow, what a p****K it is to get that rear bung out, even harder finding the hole to put it back in, I had to come in and look at the manual to find it.
There must have been some sludge built up on the rear bank because I had to do a high pressure flush (plugged radiator and front bank), nothing came out then water exploded all over the firewall, that sandy sludge crap was all over the bung.
besides that the coolant wasn't brown and just had some white flecs like dandruff it it (1 flec to 100ml).
I am slightly concerned that I only managed to put around 8.5 litres back in (I drained via the radiator, overflow bottle and the two engine bungs).
I let it run for about 15 minutes until the hoses got hot and topped off after the initial fill and got maybe a litre into the radiator
Will check it again when the engine cools down.

How do I get the air out of the hoses?

Just leave it to cool off, the third gen has the advantage of the thermostat being on the inlet pipe so all the air will work its way up, once cool top it back up and you will be fine