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Thread: How to do a radiator flush?

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2008-08-24 16:38:39
How to do a radiator flush?
Well since school is starting up again tomorrow I wanted to do flush the radiator. But I never done it before and I was wondering if you guys could help me out. I have a 98' SE-R and I was wondering if someone could right up a
step by step on how to flush the radiator?
2008-08-24 17:14:08
There is no need to flush your radiator if it is not giving problems.

Now if you want to change your radiator fluid all you got to do is drain the system. Put water in it, use bottled water.

Then start the car let it get hot, turn on the heater, let it run for 1 min. Then turn off the car.

Wait for car to cool down

Drain the system again

Then put in new antifreeze.

bleed system propely and you are out.
2008-08-24 17:37:21
easy people may disagree but this is how i do it


take the time to take your over fill bottle and drain that to. take it out and clean it. you will be suprize how much crap settles in the bottom

buy a radiator flush, add water and radiator flush and top off, dont forget the over fill bottle fill that the max line

turn car on with radiator cap off,

put heat on full blast,

squeeze the cold side radiator hose to get air out

when air bubbles stop put the radiator cap back on and let run for bout 10 t0 15 minutes to let the radiator flush work

let car cool down


repeat everything you just did with just water to get all the chemicals of the radiator flush out also cleaning the over fill bottle again. let run for bout 5 to 10 minutes

buy some 50 50 mix and water wetter (suppose to be really good for cooling) if you like and if you do buy water wetter only use half bottle (thats how good it works) you wont have heat in the winter if you use a full bottle lol

cap off or pinch the line to your over fill bottle line (will explain later).. get a nice big deep funnel.. rap tape around the bottom end of the funnle and stick in in your radiator till its so snug that it creates a seal and no fluid comes out.

pour water wetter in and fill radiator up with whatever mix of antifreez you want, when radiator is full keep pouring till the funnle is about half full, turn car on and watch all the bubbles come up through the funnle. the reason why you pinched your over fill bottle line is because all the extra water from the funnle will run in the over fill bottle filling it up all the way and it will spill all over the place

squeeze the cold side hose to help with the process of getting rid of air pockets

let run till all bubbles stop....

when all air is out here is the tricky part. you have to some how take the funnle out with out letting all the nice hot fluid spill all over the place and on your self. havent figured out a way to do that yet lol...

just pull the funnle out fast !!! top of the radiator with fluid if need be put radiator cap on check to see if your over fill bottle is on the max line and enjoy a cooler engine
2008-08-24 17:42:24
i have heard really good things about DEI radiator reflief, its supposed to be better than watter wetter
2008-08-24 17:47:02
Water Wetter is crap. It is proven to make your fluid very corrosive. I have even seen it in action on race cars where it pits out the aluminum.
2008-08-24 17:48:37
If you really want to FLUSH the system, and not just drain it and re-add coolant, buy the flush kit at your auto parts store for around $10. It hooks up to your heater hose (the smaller hoses running to the throttle body), and has a regular water hose fitting on it. drain your radiator, and leave the cap off. Then turn the hose on while connected to the fitting that tees into the heater hose, turn the thermostat to hot, and start the car. Give it a minute or two to get all the water circulated thru the system, until it runs clear from the radiator cap. Turn off the car, and drain the coolant system again. Then cap off the flush kit, and start adding water to the radiator (distilled preferrably, as it doesn't contain minerals). Fill it up until it's topped off, and start the car. The water will disappear pretty quickly, so get under the hood and keep adding water. After one gallon, add a bottle of water wetter, and then add the rest of the distilled water until the system isn't burping bubbles anymore.

The easiest way to do this of course is like Dre mentioned. Just drain the system, and add fresh coolant while bleeding the air out.
2008-08-24 17:58:50
Originally Posted by Andreas
Water Wetter is crap. It is proven to make your fluid very corrosive. I have even seen it in action on race cars where it pits out the aluminum.

not arguing with you but i have also herd the samething but that is only if you add to much of it.
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