Flushing the cooling system, any tips?
#1
Nordschleife Master
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I'll be changing the thermoswitch and flushing the cooling system tomorow, any tips?
I'm gonna drain it, fill it with water, run the car up to temp, then drain again and refill with 50/50 coolant (the right stuff) and water.
There may have been some mixed coolants in there that caused some sludge, would adding some soap to the mix help things? (What soap do they make that doesn't foam? powdered dish washing soap maybe?)
TIA,
Adrial
I'm gonna drain it, fill it with water, run the car up to temp, then drain again and refill with 50/50 coolant (the right stuff) and water.
There may have been some mixed coolants in there that caused some sludge, would adding some soap to the mix help things? (What soap do they make that doesn't foam? powdered dish washing soap maybe?)
TIA,
Adrial
#2
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Use Prestone or Zerex or equivalent cooling system flush. No suds and very good. Find the mega power 16 or 20 ounce bottle instead of the wimpy little 8 ounce bottle!
--Kevin H.
--Kevin H.
#3
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Originally posted by adrial
flushing the cooling system tomorow, any tips?
TIA,
Adrial
flushing the cooling system tomorow, any tips?
TIA,
Adrial
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#4
Three Wheelin'
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When I flushed mine I did it with Lestoil and water and ran it for a while, from my house to my uncle's. Only problem I found was that I had to rinse the system thoroughly to get the pine scent out. lol
#5
Race Car
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Get some cooling system cleaner...you can pick it up at an auto store. Use it in the first batch that's getting flushed and replaced with the 50/50.
When refilling make sure you have the system completely bled [heater dial fully clockwise, bleeder screw open, no bubbles].
When refilling make sure you have the system completely bled [heater dial fully clockwise, bleeder screw open, no bubbles].
#6
Nordschleife Master
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Great, thanks for the suggestions.
It will be good to not have to control the fans myself with the AC button (but the AC not actually running)!
I've been running with the thermoswitch disconnected.
Trevor, A friend of mine was wondering where G96 came from. Is that the designation for the 968 trans?
It will be good to not have to control the fans myself with the AC button (but the AC not actually running)!
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Trevor, A friend of mine was wondering where G96 came from. Is that the designation for the 968 trans?
#7
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Adrail,
Get or borrow a coolant system pressure tester... it makes very short work of flushing the system, and then bleeding it after the fact is a snap.
Regards,
Get or borrow a coolant system pressure tester... it makes very short work of flushing the system, and then bleeding it after the fact is a snap.
Regards,
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#9
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be carefull with so called "coolant cleaners" or "rad flush" products, they can cause more harm than is worth.
Spoke to a guy about this while ago. chances are you'll be replacing your radiator shortly afterwards..
water and hose, foreward and backflush is all you need
Spoke to a guy about this while ago. chances are you'll be replacing your radiator shortly afterwards..
water and hose, foreward and backflush is all you need
#10
Nordschleife Master
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I would stay clear of dishwasher soap. Some of the products can really attack aluminum ..... I had an aluminum garlic press (cooking tool) corroded pretty bad when I put it into the dishwasher with "Cascade" dishwasher soap.
Also, if you are going to take apart the rear end heater hose for the flush while running, cover up that damn inspection hole on the bellhousing. Coolant will leak down in and all over the clutch internals. Then the bearing surfaces will corrode up and your clutch won't fully release. Don't ask me how I found this out.
Also, if you are going to take apart the rear end heater hose for the flush while running, cover up that damn inspection hole on the bellhousing. Coolant will leak down in and all over the clutch internals. Then the bearing surfaces will corrode up and your clutch won't fully release. Don't ask me how I found this out.
#11
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Use Tide (laundry soap) and distilled water, run it through a few times (get the car nice and hot then wait until it cools for a while and drain it) until it comes out clean then flush it with distilled water (only) a few times until that comes out clear. Then refill it with your preferred coolant/distilled water combo. Works great.
It's a good idea to take out the thermostat while you're doing this to get the full system cleaned. Be aware that the cleaning will also clean out any sealers that were put into you system by previous owners, so you might end up with some leaks.
good luck.
Dal.
It's a good idea to take out the thermostat while you're doing this to get the full system cleaned. Be aware that the cleaning will also clean out any sealers that were put into you system by previous owners, so you might end up with some leaks.
good luck.
Dal.
#12
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It's DONE!
I drained, ran water through it, filled with water, drained (all with car off), then filled with water and radiator cleaner, drained, ran water through it, filled with water, drained and finally filled with coolant and water. Then I used my ghetto cooling system pressurizer (coolant resevoir cap with a schrader valve on it), pressurizied to 5ish psi (was using a big compressor with a regulator, so I was very cautious)...burped it, started the car, let it warm up a little, burped on steep driveway, went for a 2 min drive (at this point it finally started blowing heat! hooray!), came back, parked on steep driveway, squeezed some hoses, burped it again...and then began the test drive!![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
While I was in there I pulled out the sensor for the integrated radar detector the PO had installed (an old Bell, from '92 I believe) and yanked the AC condenser and dryer. The AC hasn't worked in 2 years and would be coming out anyway...so I figured why not get it done while I'm in there.![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
The temp didn't move from the bottom line for my entire test drive tonight.
And the fans worked perfectly, exactly as they should have. I used a standard thermoswitch. I think it was 96/104?
Thanks for the help all
--Adrial
Oh, as FYI...I've read everywhere that the thermoswitch was 30mm...well the one that was on my car and the new one that I installed were both 29mm. Also, the wiring was a bit tight going to the thermoswitch...is that typical?
I drained, ran water through it, filled with water, drained (all with car off), then filled with water and radiator cleaner, drained, ran water through it, filled with water, drained and finally filled with coolant and water. Then I used my ghetto cooling system pressurizer (coolant resevoir cap with a schrader valve on it), pressurizied to 5ish psi (was using a big compressor with a regulator, so I was very cautious)...burped it, started the car, let it warm up a little, burped on steep driveway, went for a 2 min drive (at this point it finally started blowing heat! hooray!), came back, parked on steep driveway, squeezed some hoses, burped it again...and then began the test drive!
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
While I was in there I pulled out the sensor for the integrated radar detector the PO had installed (an old Bell, from '92 I believe) and yanked the AC condenser and dryer. The AC hasn't worked in 2 years and would be coming out anyway...so I figured why not get it done while I'm in there.
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
The temp didn't move from the bottom line for my entire test drive tonight.
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
Thanks for the help all
--Adrial
Oh, as FYI...I've read everywhere that the thermoswitch was 30mm...well the one that was on my car and the new one that I installed were both 29mm. Also, the wiring was a bit tight going to the thermoswitch...is that typical?