Cooling system flush... AGH
Cooling system flush... AGH So I did a cooling system flush today, bought a jug of orange dexcool, water wetter, and a couple jugs of distilled water. I drained the radiator, stuck a hose in the top, and ran the car for a bit on and off, id say a quart at the most drained from the radiator, I thought it would be more. Then I started running the hose through it to flush it out and only clear water was coming out the bottom, the thermostat should have opened and closed by then? The car took barely took a gallon of dexcool... What am I doing wrong? theres alot of crap built up in the filler neck so I need to flush the hell out of the entire system, can someone tell me exactly how to do a thorough flush? Thx
So I did a cooling system flush today, bought a jug of orange dexcool, water wetter, and a couple jugs of distilled water. I drained the radiator, stuck a hose in the top, and ran the car for a bit on and off, id say a quart at the most drained from the radiator, I thought it would be more. Then I started running the hose through it to flush it out and only clear water was coming out the bottom, the thermostat should have opened and closed by then? The car took barely took a gallon of dexcool... What am I doing wrong? theres alot of crap built up in the filler neck so I need to flush the hell out of the entire system, can someone tell me exactly how to do a thorough flush? Thx
The best way to flush your system is to remove the t-stat and bolt the housing back up. Then stick the hose in the radiator with the plug open at the bottom of the radiator and run the engine for 10 minutes. This way you will get every single drop of old coolant out. But take the entire pet **** valve off so the coolant runs out of the radiator faster, otherwise it'll take forever for the water to run clear.
If you want to, get a bottle of radiator flush. After the water is nice and clean after the first 10 minutes, close the plug and let the engine run with the flush in it for another 10 minutes. Then open the plug and run it for about 5 minutes and let the water and flush run out of the system. Your done.
if the thermostat is in then you really need to have the radiator cap on so the system pressurizes which will help the coolant or water flow through the system.
and draining by the radiator petcock only leaves a lot of fluid in the block, you really need to pull the block drains- one above the starter that'll use a 5/16" allen and there's a 16mm allen near the alternator, both are brass colored. Otherwise you're refill of coolant/water mix will be way off- 50/50 + however much water left in the block = < 50% coolant and > 50% water in the system.
If you can't get the block drains, then I don't know if parking on a downsloping angle will help at all at the radiator petcock, only other thing i can think of is compressed air to blow through the system, or a special coolant flush/change machine that forces fresh coolant through such as at a radiator shop.
and draining by the radiator petcock only leaves a lot of fluid in the block, you really need to pull the block drains- one above the starter that'll use a 5/16" allen and there's a 16mm allen near the alternator, both are brass colored. Otherwise you're refill of coolant/water mix will be way off- 50/50 + however much water left in the block = < 50% coolant and > 50% water in the system.
If you can't get the block drains, then I don't know if parking on a downsloping angle will help at all at the radiator petcock, only other thing i can think of is compressed air to blow through the system, or a special coolant flush/change machine that forces fresh coolant through such as at a radiator shop.
if the thermostat is in then you really need to have the radiator cap on so the system pressurizes which will help the coolant or water flow through the system.
and draining by the radiator petcock only leaves a lot of fluid in the block, you really need to pull the block drains- one above the starter that'll use a 5/16" allen and there's a 16mm allen near the alternator, both are brass colored. Otherwise you're refill of coolant/water mix will be way off- 50/50 + however much water left in the block = < 50% coolant and > 50% water in the system.
If you can't get the block drains, then I don't know if parking on a downsloping angle will help at all at the radiator petcock, only other thing i can think of is compressed air to blow through the system, or a special coolant flush/change machine that forces fresh coolant through such as at a radiator shop.
and draining by the radiator petcock only leaves a lot of fluid in the block, you really need to pull the block drains- one above the starter that'll use a 5/16" allen and there's a 16mm allen near the alternator, both are brass colored. Otherwise you're refill of coolant/water mix will be way off- 50/50 + however much water left in the block = < 50% coolant and > 50% water in the system.
If you can't get the block drains, then I don't know if parking on a downsloping angle will help at all at the radiator petcock, only other thing i can think of is compressed air to blow through the system, or a special coolant flush/change machine that forces fresh coolant through such as at a radiator shop.
No pressure is needed in the cooling system for the water pump to push water through the system.
When I did my flush, I removed the reservoir and rinsed it out. Then flushed the radiator and all the other crap with hose water for about a half an hour.
When I was done the water was crystal clear.
When I was done the water was crystal clear.
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The easy and "lazy" way to do it is to just drain the radiator once a year, and fill that up. Been doing that for a long time, and it's just enough to "refresh" the system, and not be a total pain in the ***.
Staging Lane
Joined: Oct 2008
Posts: 62
Likes: 0
better have made sure u got all the dex out b4 puttin in the green. very bad to mix. btw unless youre the engineer that designed the system i suggest u stick with dex. people put in alot of time and effort to firure out what works and what doesnt...
grab one of these and drain your radiator, close the petcock, then pump it up to the pressure on the cap, then open the petcock and watch out. couple times should get everything out.
i would stay away from the flush additives too.
switching from dex-cool to green is a bad idea as well. they use different gasket materials. you are asking for leaks.
i would stay away from the flush additives too.
switching from dex-cool to green is a bad idea as well. they use different gasket materials. you are asking for leaks.