94 Q45 coolant flush help

[kotex]

Crew, I am planning to flush my coolant this weekend (94Q). Is there anything I should know besides opening the heater core? I am a mechanical retard and haven't done this before. Is it a matter of opening the radiator drain plug, letting the coolant drain and flushing with water for a few minutes (water hose) or should I flush with a few gallons of distilled water?

I plan on using a 70/30 fill ratio (Florida summers) and some wetter. Where is the Tstat by the way:oface as I would like to change that also.

Please let me know the best procedure to perform a good flush, Thanks fellas!!

[elwesso]

I did this and posted a procedure... might search for that but Ill give you the cliff notes...

Best thing to do is replace the Tstat at the same time... take out teh Tstat, then drain the coolant, refill with distilled water, and keep going until you drain clear water... Mix everything up and put the Tstat back.....

Open the heater core by press holding OFF on the HVAC controller, press warmer 3 times, and defrost 2 times.. Should have 43......

[elwesso]

From then on you can just do a radiator drain and refill every year and that will be sufficient.....

[DAEDALUS]

Follow the lower radiator hose up behind the fan to where it's clamped. The tstat is behind the metal cover the hose is clamped to--3 bolts and some RTV.

[911/Q45]

Take the block plugs out, if you can. The owner's manual shows you where they are. Tough to get at, but a lot of sludge can accumulate at the bottom of the block and they are the only way to really get it out.

[Jeff Williams]

I have heard bad things can happen, if you are not creful about reinserting the block plugs. It IS an aluminum block, so be careful.

[Q45tech]

If you use a chemical scale remover [Prestone/Zierex flush or super flush] prior to draining you must change the thermostat as the chemicals will react and destroy the rubber seal surround, even some metal................look inside the connector pipe [between the drivers side rad hoses], the is a sacrifical anode and severe corrosion will be [present inside this metal pipe]......good to replace it after the flush.

Check all hoses for crunchiness [causes by oxygen permeability].

[VA99Q45]

Do not remove the block plugs. They are very hard to get to and you may have a leak there in the future.

When I did mine, I fill-up the radiator with distilled water. Run the car to the operating temperature and drain. Do this 10 times before puting the coolant.

[elwesso]

Thats what I did, except if you take out the Tstat you can just run thec ar foa few mins at a time to save a little bit of time...

[AZhitman]

Ixnay on the block plugs...

I'd rather take the chance on some crud than to have one leak.

That's no fun, and ALMOST caused me to sell my Q within a month of ownership (fortunately, NICO members hooked me up).

[elwesso]

Definitely...

One thing I learned about coolant changing is NEVER TOUCH the block plugs... By 100k or so theyre fused in there, bad idea...

[Q45tech]

Strange we do it all the time with 60k/120k/180k/ 240k services.....never had problem with block plugs just takes time, the proper tools and asbestos [sic] gloves/burn cream.........must be done warm.

[3Q Jay]

hmmm. last time i checked this thread, DAEDALUS had the last reply. Well, without further insight from the board, I did this yesterday [also diff change w/ redline 75w90 gear]. I did do the block plug on the right side [easy access], but not the left. while it was out, I ran water thru w engine off twice, with the plug finger tite and engine running until t-stat open inbetween. for final install, i cleaned the plug good [btw, found no discernable particulate at all anywhere in the system], applied thread sealer [plmbers tape] and reinstalled. at time of install, the block was uncomfortably warm to the touch, and i tightened to ~15 lb-ft. I'm slightly concerned though, after reading the rest of this thread, because it seemed like i turned the plug in a long way without a lot of increasing resistance [no, I'm sure I didn't strip it, and there was never a peak of torque after which it relaxed], just a fairly constant 10lb-ft. I finally deemed it good enuf, just because i was afraid to twist much further. not a ton of running time or cycles yet, but also no leaks found.

anything that the masters would recommend different?

3.5 qt dex cool, 12 oz redline WW, 6.5 qt distilled H2O.residual, well my guess is 99% tap water.

[AZhitman]

Well done.

[elwesso]

Defintely.. great job..

When 911/Q45 said there may be sludgey stuff in the bottom, I was unconvinced that it would just come out with the rest of the coolant flush...

I dont know, it certainly made it easier I think... It took me like 2 hours to do it my way, but a lot of it was down time..

[3Q Jay]

thanks guys for the replies.when Q45tech talks about the sacrificial anode- I haven't examined this pipe or anode yet. is the anode replaceable seperate from the pipe, or must one buy the whole pipe? btw, to confirm... this is the 'midpipe' between the lower rad hose segments.also for hitman-glad to hear you've got your cooling woes sorted out. reading your posts originally inspired me to find out more about water wetter and the rationale for a less than 50/50 af/h2o mix.

[elwesso]

Your correct, and you misunderstood Q45tech..... THe midpipe what your talking about is the sacrifical annode and you will see some scaling in ther emost like.y... Mine looked like it had barnacles but I didnt know to replace it when i was in there, but its not like it was hurting anyhting so I didnt do anything with it...

[3Q Jay]

got it Wes, thanks.

[Q45tech]

By design this pipe location/gravity/cooling allows the dissolved minerals to settle out and attach to the pipe. Where they are then removed by replacing the pipe at frequent intervals, just like the hoses!

Using a chemical flush will just dissolve them [maybe] allowing them to settle somewhere else..........causing problems.

Where did all these cruddy clumps come from? the water, the radiator aluminum, the engine aluminum AND broken down additives in AF which did their job.Why OAT AF and distilled water and no other additives are better in many ways as long as you keep the PH correct.

[3Q Jay]

Why OAT AF and distilled water and no other additives are better in many ways as long as you keep the PH correct.

thanks for the reply. ok, AF=>antifreeze. OAT =>????

btw, no chemical flush here!

[maxnix]

OAT = Organic Acid Technology

See also:http://www.penray.com/bulletins/esi_coo ... es...d.htm

[3Q Jay]

thanks, Brian--very educational.

Jay

[Q45tech]

The problem with chemical coolant flushes is they are mostly one formula fits all: all iron, part iron block, and all aluminum engines.

They have unnecessary chemicals in them to deal with iron [ferric/ferrous] compounds that are not present.

[Victor]

Is this Dex Cool I saw mentioned a gold colored long life antifreeze they use in some new cars? If it is a mechanic told me if you mix it with regular ethylene glycol based antifreeze the two won't mix properly and will even change to a gel that will ruin your engine.But anyway, from reading this thread it looks like its not a good idea to remove the drain plugs in the engine. So if I drain the coolant using the plug on the bottom of the radiator is there anything else I need to do like open up any air vent plugs like on a G20? And if so where is it? I saw some complicated procedure to open up the heater core, which I don't really want to mess with. Any recommended antifreeze (ethylene glycol based) brand. Guess I should also used distilled water.

[maxnix]

Fill and drain a couple of times with distilled water then perform final fill.

35% will give protection to pretty serious winter conditions yet allow better heat transfer at higher levels.