Coolant flush questions

[elwesso]

I am going to do a combined Tstat and coolant flush, and I need to know

1. What do i do with the used coolant2. What is the best coolant to use3. Should I use any of those products that remove deposits4. Should I get one of those prestone radiator flish kits (the one where I have to cut a hose into one of the coolant lines)

I know i need to use 1 bottle RLWW, 70% de mineralized water, 30% AF....

Am i forgetting anything else?

[nuQ]

maybe i'm a rebel/badass, but i dumped my used fluid in a secluded field,,,,any signs of wildlife were absent!!!LOL I used the orange coolent(prestone), i believe a gm upgrade, recommended by fred, just make sure that all the old "green stuff" is flushed out. can't mix!!! after dumping all the coolent from the radiator, i kept re-filling with distilled water until it was running clear when i dumped(putting the cap back on, letting Q run for 5-10 minutes to let distilled go throughout, about 5 or 6 times). i then put it a little less than the gallon of coolent and the redline water wetter, then topped off with distilled water. should give you the correct mixture, or close to it. any questions, ask.

[nuQ]

i forgot,,,,, i did use the prestone flush at the start of the procedure, just to make sure all was clean. i didn't cut any hoses, just poured the flush in and let it flow throughout. some on the sight may frown on this "shock treatment", but it worked out OK for me. use your discretion.

[elwesso]

I personally dont like the idea of cutting a hose...... Its just a leak and a PITA waiting to happen...... I think what im going to do is to flush with regular water to begin with, and then the final fill will be distilled water.....

Did you use the prestone radiator clean stuff or the prestone radiator flush???

[forecast]

flush the coolant down your toilet or ask the local autozone if they'll take it.

if you're daring you can try pulling the drain plugs on the block and not cut any hoses. This will dump 99% the fluid out of the block - but is a HUGE mess.

[elwesso]

where are the block plugs..... Im not concerned about a mess.....

Is this something that would be easier to take it somewhere to have it done, or is this a reasonable DIY.......

[forecast]

both block plugs are on the outsides on the block below (and inside) the exhust manifolds. The RH is located in the middle, the driver's near the rear.

They are fairly high up on the block but need to accessed from below.

see the photos of my engine at http://www.q4sale.com/rebuild.htm In the seventh picture you can clearly see the driver's side plug. It's in the bottom left of the photo. It's the small plug with the white collar (selant).

[elwesso]

Is it completely necessary to use those plugs to drain the coolant (i know it says so in the manual, but does it HAVE to be done to get the job done right)

[paintwgn]

Prestone reverse-flush kits work well. They allow the water to bypass the thermostat and clean out the system. I've been using them for 40 years - they don't leak. Just be sure you use good all stainless hose clamps and cut the correct hose-the one going from the heater core to the block.

[AZhitman]

Do NOT remove any plugs.

There is a procedure in the manual for opening the heater core.

[elwesso]

So how should I go about doing the final fill with distilled water and coolant?

[Q451990]

This takes a little (ok, a lot) more time but I just buy about 6 or 8 gallons of distilled water. Run the flush first - then drain the radiator. Refill with distilled water only, start car, let it warm up so that the t-stat opens, turn off car, drain radiator, refill with distilled water. Repeat 6-8 times. After four or five gallons, I suspect that everything is diluted down to whatever everything would be with just draining with the block plugs.

After all of this, I top everything off with the correct amount of coolant and Redline Water Wetter.

Heath

[elwesso]

To save myself the trouble, how much coolant do you need to add to a full system.......

[elwesso]

Oh yeah, and I looked at the heater core hoses, and I dont think i would be able to get one of those flush kits on there!!!!!

[forecast]

Do NOT remove any plugs.

I believe Azhitman had a problem with a plug stripping the threads out of the block as it was removed, but I'm fuzzy on the details, but I think I left a perment mark in his psyche. Both of mine came out and went back in without much fuss or leak.

[elwesso]

Prestone reverse-flush kits work well. They allow the water to bypass the thermostst and clean out the system. I've been using them for 40 years - they don't leak. Just be sure you use good all stainless hose clamps and cut the correct hose-the one going from the heater core to the block.

Did you put one on a Q??? I dont think there is enough room in there..... What a surprise :rolleyes

[AZhitman]

I believe Azhitman had a problem with a plug stripping the threads out of the block as it was removed, but I'm fuzzy on the details, but I think I left a perment mark in his psyche. Both of mine came out and went back in without much fuss or leak.

No, these were the UNTHREADED (welch) plugs you refer to (detailed in another thread).

I have no experience with the threaded ones, but I can't see much reason to remove those either, especially given the aluminum block.

[paintwgn]

Did not put a flush kit on my 91 Q -you're right-there is not enough room. I haven't flushed my system in 2 years,so I don't remember exactly how I did it. I think I disconnected the heater hose at the temperature control valve and put the end of the hose up to the valve. This forced the water back thru the heater core-thru the engine block-thru the lower radiator hose-up thru the radiator-and out.

[natsoundup]

I did it a couple of years ago...and I remember draining the radiator over and over...after filling it up. I also used a series of codes that were provided in the mini-manual to open up the thermostat or heater core....

I think I filled and drained the radiator 5 or 6 times before adding water, anti-freeze and wetter water.

I think Infiniti recommend un-doing plugs on the engine...but others strongly advised against it....

I guess it's probably time to change it again.... two years comes and goes pretty quickly.

[Jberger]

Regarding the prestone flush treatment.

I know that T3 has me pour in a bottle 1/2 in my roadtrip to have the flush performed, so I think we can say that's the "approved" manner of service. I run the car for about 120 Miles after the treatment so you'll need to leave it in long enough to work.

I believe Dennis is against using the block drains as they can be easily stripped, then you are in for a major headache. While they make the job easier you have to wiegh the risks of stipping the block against, the additional time of multiple flushes.

Make sure to use distilled water during the change and you can use the orange coolant or the nissan green, but the orange is less expensive. Note, the Nissan green I believe is chemically compatable with the orange, but standard green antifreeze is not. So if you don't know what's in there, you need to perform a complete flush, making sure to open the heater core, before you switch to orange.

[nuQ]

i did the same system that heath described. like he said, time consuming, give yourself the afternoon, but not all that difficult. after each re-fill with distilled i let the car run with the heater set to high then waited until i got hot air blowing, was then sure that the thermostat was open and the coolent was free-flowing throughout the system. when i drained the radiator at the pet**** and got clean water for two consecutive times, was sure that 99% of the old was flushed. most on this site recommend around 30% coolent, maybe a little less in the summer and more in the winter(assuming that you're doing regular, seasonal changes---i'm sure most of us do one a year so a 30-40% coolent level should be around ideal). at this range, with a little over 10 quarts capacity for the Q, around a gallon of coolent should be used, along with the redline. after the last radiator drain, i just poured the redline water wetter along with the orange coolent and topped off with the distilled. doing it this way, you are sure exactly how much coolent is in the system and the correct ratio.

[elwesso]

Ok let me do a quick recap....

Leave the radiator flush/cleaning stuff in the engine for 100 or so miles, keep refilling with distilled water until you have clear water coming out, then put in the coolant and wetter....

And since I am doing my Tstat also, should I do it before or after?? Is there anyway I can just take out the Tstat to make flushing easier (incase it doesnt fully open)

[Q451990]

It's an RTV Gasket, so you'd have to re-seal it and let it dry with no t-stat before hand. I've thought it it, but it would be a pain... maybe you could use a make-shift rubber gasket during the flush time?

Heath

[elwesso]

Ok, so doing it before I do everything else would be better?

Also, is the Tstat right next to the radiator cap hose??? (the one that is readily accesible......)