because of the cars last owner leaving the car sitting with tapwater in the engine for over a year, it has developed corrosion in the block. I gave it a big flush originally , but everytime i fill it up and drain it out poo brown water comes out. I am hoping that the problem is not terminal as all the work I have done painting the enginebay will be in vain. I have heard you can put caustic acid in the engine for a little while, but I am worried about the hoses and gaskets. Is there a way to flush the block and remove all of the rust and scale? oh and I just found out that the A14/15s have a different thermostat from the 10/12s. and all along I had been buying normal A12 ones from repco.. sometimes buying genuine nissan helps. though 20 bucks is a fair whack for just a thermo!

bump

You can get a radiator flush. If it's cheap, get 2 bottles. It's worth the trouble so you can keep your coolant green in colour.

It's normally in the area where the coolant is.

I'd also get a bottle of CLR and swish it in around your radiator for 15 minutes (With it off the car after flushing the engine with radiator flush).

My 3 favourite metal treatment products:
1. Emertan (Tanin Phosphate rust converter)
2. Emerclean (Phosphoric Acid based metal cleaner)
3. CLR Great for cleaning nuts and bolts. More Internationally available.
4. Emerguard. A brown Rust treatment paint. Great for underbody and structural metal sections during a rebuild. The car will never rust again (If kept dry).

The Emertan, Emerclean and Emerguard can be got near Tempe, on the Corner of Canal Rd and Princes Hwy. About $100 for all 3, is enough for one Datto rebuild. Opposite from the pub. (Pub on many corners in AUS)

Chris