Hello! I have a 97 camaro V6 with the 3800 series engine. It started overheating and leaked coolant yesterday. The coolant came from the heater hoses. Anyway, had it towed to mechanic and they said the radiator is totally blocked up and we need a new one and a new heater hose. After looking around I believe I can change all the stuff out myself (I’d save around $800...), but I want to know how do I flush out all the old coolant and do I do it before taking off the old radiator? Is there a way to do it with the radiator off (that would be awesome). Or do I have to do it after putting on the new radiator? I was thinking I’d just keep adding water running the car, cooling off, draining, add water, run car, cool off, drain, until it looked pretty clean when it drains, but if the radiator is blocked up I don’t know if that’s the best way to do it.

I’m also going to change the lower radiator hose, overflow tube and reservoir. It’s pretty gunked up. If there’s a thread or link on how to flush out the coolant please direct me to it. I look forward to whatever advice you guys can give!

I’ve put in new upper radiator hose, upper and lower manifold gaskets, thermostat, maf sensor and iac valve. These things were replaced in probably April/May this year. I don’t remember but it was recentlyish.

 

while you have the radiator out pull the thermostat and before installing a new one run a bunch of water through the engine. unhook both heater hoses from the engine and the heater core at the firewall and run water through the heater core both directions, dont put allot of pressure through it, its not designed to hold up to high pressure. garden hose should hook up ok. after unhooking from engine and heater core run water both directions through heater hoses before re installing. there's a flow restrictor in one of them that can get plugged, its to slow the flow so heater works better.

 

Thank you craby! I really didn’t want gunk in the new radiator. I’m replacing the whole heater hose assembly too so I won’t have to rinse the old one out. I wouldnt have thought about the heater core flush though so thanks for adding that in.

When im done and ready to put in coolant, use the 50/50 dex cool?

jenn

 

Personally I hate dex cool that is what plugged up your radiator and eat your intake gasket. I would go with the more basic green stuff. Keep in mind the green stuff is really bad for the environment and will kill anything that consumes it. The orange/brown dex cool is easier on the environment. I always recycle the green stuff at my local parts store.

You are not going to get the best flush because the engine will be cold. I would drive it awhile and do another flush,, use the Preston flush cleaner.and I like to use distilled water for the final fill. Always follow the instruction on the container of the coolant you bought for mixing.

 

I use green stuff

 

Ok! See I was thinking I should use the green stuff but I didn’t think I could. I’ve read that the dexcool lasts longer but for the last 5-6 years the coolant has always been ugly and we’d had it flushed before. So if I can safely use the green stuff (it’s what our corvette uses) I think I’m going to use it. I’ll just have to drain and refill every 30K miles, correct?

Next- after I do all the work and then go to get ready to put in coolant, do I put coolant and water OR just water to get a better flush with a hotter engine to make sure there’s no more dex in it? Then drain all water again refill with 50/50 mix of green stuff? I keep thinking what if there is still a little dex cool in the system. I don’t want to break the car or mess something up.

*edit*. Since one of the heater hoses popped off and coolant got EVERYWHERE, can I rinse the whole engine off with water- and if yes what parts should I NOT get wet?*. Thank you!

 

Coolant should be changed 3-4 years. Miles don't really matter since its a chemical break down.

Avoid hitting the PCM (passenger side between the inner fender and the firewall). Try to avid the coil packs. I have never been a big fan a pressure washes in an engine compartments.

You can flush with just water. Step one: remove about a quart of coolant from the radiator add in the flush/cleaner. Drive car for a day or two (3) 20+ minutes runs min. Drain and replace coolant with water, drive a couple more days and drain. Fill up with either premixed or distilled water and concentrated antifreeze. IF either of the hot flush where really dirty you may think about another new thermostat. Sometimes the cleaners and heat can dislodge some hunks of crap, they could get wedged around the thermostat.

 

Thanks for the info! Those steps seem easy enough to follow. I wasn’t gonna pressure wash the engine, just run some water over it to rinse off the coolant, I just didn’t want to wet something that shouldn’t get wet!

 

So I read that I can drain the heater core, also that I can remove a drain plug from one side of the block and a knock sensor from the other side. So far I think I’ve located the knock sensor on the driver side maybe but I don’t know how to remove it. No idea where the drain plug on passenger side is or heater core. So I’m kinda stuck and I don’t know where my Haynes manual is which is frustrating.

 

go here and download factory service manual, 96 should be good for yours. https://www.mediafire.com/?40mfgeoe4ctti