Thread: Flushing coolant 03 gtp

Did the LIM gaskets a few months ago + went with Dexcool. I want to flush coolant then move to green coolant now. In terms of methods there seems to be a lot but someone critique the following method:

1. Remove lower rad hose & rad cap to drain coolant
2. Put rad cap back on
3. unhook upper rad hose, take garden hose and send water through upper rad hose until clear water comes out the lower rad hose
4. I am thinking this will take care of the engine part of the coolant flush?
5. As for the rad, remove rad cap, block off upper rad hose, leave lower disconnected, take garden hose and send water through until clear
6. Reconnect upper & lower, fill with green coolant 50/50 (up to top of rad cap & fill overflow to the cold point), put rad cap back on
7. Open bleed screw
8. start car & let run until steady stream of coolant comes out
9. if after 5 minutes stream is not steady, shut car off pull rad cap off, fill again and repeat from step 7 onward

How does that sound?

If you do it that way your not getting the coolant out of the block. I pull the upper rad hose with a hot engine and shove the garden hose in there until the thermostat closes hook the hose back up and run the engine until the thermostat opens again then repeat until clear water comes out. Do this with the heater on high.

right idea, wrong way to do it.

remove the thermostat,(put the housing and hose back on) remove the upper rad hose from the rad, open the rad cap, put hose in rad cap opening, turn hose on, start the car, and all the coolant will pump out the upper hose to a bucket on the ground under the upper rad hose. run the car till clear water comes out the hose.

turn the hose off, run the car some more so more water comes out.

put it all back together and dump a gallon or so of full strength green coolant of your choice. bleed the air out and done.

damn $hit, I tried bleeding system with car up and rad full still overheating. I figured I was the problem so took it to a shop to have it flushed & replaced with the yellow antifreeze. My wife picked up the car and these asshats did a glycol flush & said supercharged engines needed it, wtf is a glycol flush?

Car still overheating!! sitting 212 degrees most of the time - therefore not driving it.

So system flushed
new t-stat (checked if it worked in boiling water)
LIM gaskets done few months back

what do I do next?

lol wut?

They lied to you, any flush will work, NA to SC motors are the exact same.

212 is not hot and not overheating, BUT, thats sorta above the normal crusing around temp. Most will run around 195ish and up to 210-215ish when stuck in traffic.

Try bleeding the air again.

Do this, start the car and let it get up to temp before you do anything. Then have someone hold the throttle at 2,000 and break the bleeder open real quick, for like only 2-3 seconds, do that many times, it'll help cycle any air out.

yeah but these cocksmokes at econoy lube bled the system apparently. I would be surprised if the car is supposed to run at 212 degrees. I think the factory GM setting is that fans go on high at 205!?

fan settings are 214 and 226.

Hmm so is there anyone on the site that doesn't **** their pants when the car rises about 100/212 degrees? Perhaps my expectations are off? what does your car run at?

Drove the pig again, temp all over the place, one second 220 then 10 seconds later 205. Cracked the bleeder and a nice steady stream. Barely loosened the rad cap & got a small pressure release. Actual rad cap was not hot at all...

are the fans coming on? both of them?

if you put the a/c on both fans should turn on while in park. good way to see if they both work.

Maybe your water pump is on its way out?

Fans are coming on, I did notice something strange though. I could be at 210 degrees feeling uncomfortable, then take a corner quick and it would instantly lower 10 degrees. Seems like every sharp turn of the wheel would lower temps. How can I diagnose a water pump?

maybe try re bleeding the system. heres how i like to do it.

open rad cap, top it off, leave it open, idle car till the fans come on (this can take up to 15 minutes) if the fans are on the t state has opened, then open the bleeder screw till a steady stream of coolant comes out. top off the rad, shut cap.

and some times massaging the upper hose to get any air out if it while the fans kick on.

in your case it may be necessarily to do the above while on car ramps to raise the rad cap opening higher than the block.

my regal runs at 1 tick over 1/4 on my gauge while driving and 1/2 way up if left to ldle. but no higher than that.

Tried this method and things still suck, I didnt leave the cap off though, just cracked because coolant kept leaking out. A certain points aroud 205 degrees I was actually getting no coolant at all from the bleeder, wtf?

how long did you leave it open? if you have a lot of air in there it could take a minute or so, and how many turns did you turn it to open it, can take 3 or 4 turns to bleed it.

how many miles? ever do the water pump?

your heat works?

left it open for 20 seconds all air, I opened the bleeder at least 3-4 turns
156k miles, not sure if waterpump has been done but not leaking
Heat rocks

maybe the bleeder is clogged, you saw nothing come out no bubbles?

if you keep un turning the screw it comes out.

I have a good mix of Dex in mine, running a 180* thermo, and Mine rarely hits 210* Usually closer to the 200* mark. Mind you it will get closer to the 210 point during the hot summer months if it just sits, but out on the highway it goes back toward the lower 200*s.

Before you go crazy over me not having the mods to support the 180, I don't care. Car runs perfect, checked with a GM Scantool from the shop. I run the 180 because I don't like the higher temps during the summer months, keep in mind avg 105+/- in Oklahoma in the summer, she needs to be cooler. During the cooler months I just start her up and let her idle while I get ready (perks of having a closed garage).

Solved i think but grrr...

Car continually overheating at first after lim makeover. I did a new temp sensor, t stat and rad hoses. During the first few overheating cycles i figured air in the lines and got tons of advice on the procedure as i thought i was doing it wrong. Still hot as hell. Next figured new thermo sucked so threw it in boiling water and it opened. Check there. Figured more air in line or clogged system. Got coolant flush and still problems. Not much choice after that. I figured rad but to my surprise it was brand new. Therefore must be waterpump. Purchased one and slapped it in tonight. Yeah completely moving the power ateering pump was a bad idea lol. Anyway filled her up with coolant and bought a new rad cap too. Fired car up and once it got around operating temp it went sky high again. Dog shiet! Gotta be air! NOPE!

At this point i have thrown a few tools and cursed many a thing. When i tried the bleeding somwthing dawned on me which should have a hellish amount earlier in the process. When i revved car up with bleeder open no coolant i thought air pocket but also thought about the thermostat again. So i pulled out that mf'n pos and fired car back up... Temp was awesome but way low therefore i am thinking thermostat although it opened in boiling water, was playing me for a fool this whole time. Gonna grab another one and hopefully it will work. Damn t stat this whole time