How do you flush? - Cars & Trucks

Follow these instructions: http://www.wikihow.com/Flush-a-Radiator

drain coolant system locate heater cores hoses going through firewall you need to buy the radiator flush kit at any auto parts stores. remove heater cores hoses from one end or buy extra long heater hoses same size as heater core hoses in vechicle at auto parts store use the flush kit when you flush through one of the heater core hoses let the other hose drain in a drain pan when you use home garden hose use low water pressure dont use garden hose to the max or you will rupture heater core. your best bet let radiator shop flush whole coolant system. because heater cores hoses are in a tight spot.make sure engine off if you just going to flush out heater core only .after flushing heater core good time to replace heater core hoses.if job too hard or complicated let radiator shop flush out radiator the engine block and heater core because if radiator stopped up or engine block stopped up the gunk and rust will reenter plug up heater core.if you tight on money you can flush out your own radiator.drain out radiator using large drain pan. remove top radiator hose and remove bottom radiator hoses connect to water pump.use garden hose with flush kit part with water pressure not too high put garden hose to top radiator hose run water until clear water run out bottom radiator hose in drain pan,the flush out engine block remove thermostat.if you had another spare thermostat housing with RTV SILICONE SEALANT THAT HAS SET UP INSTALL THERMOSTAT HOUSING BACK TO ENGINE WITHOUT THERMOSTAT FLUSH OUT THE ENGINE BLOCK, WHEN DONE INSTALL NEW THERMOSTAT THEN INSTALL ORIGINAL THERMOSTAT HOUSING WITH NEW ORING WHICH YOU BUY AT DEALERSHIP.IF ALL SOUND COMPLICATED LET RADIATOR SHOP FLUSH OUT COOLANT SYSTEM.

take of the top heater hose, use a funnel to insert flushing agent connect hose and flush through.with radiator cap off.take off bottom hose to radiator to drain system,reconnect all hoses,fill expansion tank to fill system...

flushing gets any particles out of the system, the tiniest grain can ruin an auto-box so its good practice to flush the system at the major service. It wont do damage so long as the gearbox isn't stressed during the flush - E.G. Don't drive the car with a box full of flush ;-)
I say FLUSH - the gearbox is very susceptible to dirt and grit - keep it as clean as humanly possible.

your choices are take it to a radiator shop for a pressure flush,or you can try a chemical flush from cans that they sell in parts stores.a chemical flush does not even come close to a pressure flush.but you will need to flush engine too.

your core is clogged. This is what I was told by Hibdons Tires Plus, unless you specify them to flush the core when they flush your coolant it doesnt get flushed. It is simple to do yourself. disconnect both hoses running from firewall where they connect to engine. spray water from the garden hose through both of them untl it comes out clean. it took me about 15 minutes to flush mine and then I had heat again. I had my coolant flushed and then flushed the core about a week later and all kinds of junk came out of my core. give it a try, I think it will work for you.

change the parts then have it flushed

Flush/replacde means the same thing. I have never known or been told of a difference between the two.