$120 coolant flush.

Somebody give me one good reason why you should pay 120 rats for this service. Am I correct in assuming it just involves draining all the coolant and replacing it.

imacsae,
A good reason? You have too much cash in your wallet and need to dispense with it quickly?

You are correct, in most cases it's simply a drain and fill, which, unless there is a problem should be all that is necessary. With modern engines that don't have all cast iron parts, I wouldn't run one of the "cleaner", "conditioner" or whatever else they call it in there. If you really want to do make sure you get most of the old coolant out, drain, fill with distilled water, make sure your heater is set to hot to flush out the heater core, drain that after running up to temp and then fill with a 50/50 mix.

Some tout the use of a flush, putting a "T" in the coolant hoses. If you're changing the coolant out every two years, there should be no need for a flush.

Bogatyr

Flush is more recomended for a cooling system that has been neglected for a couple years and is pretty nasty.

And $120 is too much for a flush... had one done in an old truck for only $79 at the Express-lube.

doing it is quite simple.
Materials You Will Need
-water house
-1 gallon of collant
-2 empty 20oz bottles or something simlar
-bucket or oil drain pan
-collant cleaner
-possibly a set of pliers if petcock valve is tight

First you lossen and drain the coolant from the petcock valve. Next you wash your coolant system out. Close petcock pour cleaner in system and put water in till it reaches right level, run ur vechile for 5-10 minutes, drain the cleaner and water be carefull it will be hot. Next leave the pet cock valve open and wash out system some more. then take to 20oz bottle and put a bottle of coolant in and bottle of water and so on and you want to have a 50/50 mix. after you are done make ur collant bottle a 50/50 mix and throw it in the back of ur vechile incase you need to add more or you notice ur car is running at to high of temps.

The local Stealership only chagred $65.

If you do it yourself it can be a pain loosening the engine block drain plugs. They're hard to get a socket onto.

Blackjackbender's insturctions work but you have to drain the block in addition to the radiator, the air relief valve on top of the intake manifold needs to be opened when you fill the system back up (close it when it overflows then top off the system), and you might need more coolant.

You dont really need to do it. Easier way is to just drain whatever you can from radiator, then stick hoose and make water running through system, while engine is idling. That way incoming water will get out whatever left of old coolant in engine. Just need to figure approximate amount of how much of it will left in there, or use tester later on, to get proper mixture of antifreeze+water.

I could never find the engine block plugs... I just did a drain, fill with water, run, drain, fill with water, run, drain, fill with mostly-antifreeze...

Anyone putting water from their garden hose (or any other household source) into their radiator is doing it a big dis-service. ALWAYS use distilled water in the cooling system, otherwise you're going to have mineral deposits in there.

Brent

In a pretty thorough search for info on how to drain and fill the coolant system it seem's that there is no reasonable easy way to do it. The best solution's found were from:

XmtbX00 who was going to drain the radiator then add water (distilled of course) until it ran clear. Next he would fill the radiator with pure coolant and get about 40/60 ratio of coolant which is probably good enough for a temperate climate. If not he was going to drain the radiator again and add some undetermined ratio of (which I calculated to be 17/83 ratio or 1/6) if the capacity of the radiator is about 1/3 that of the total system.

I will probably do this tomorrow unless diassuaded but it seems to be a good way of doing it. Besides, a memeber max had stated you must remove the alternator to get at the left engine block bank, which I would rather not do. Today I tried getting at those damn plugs and it ain't fun.

is it okay to clean it with tap water?

No, it is not a good idea to flush with tap water... if you must, make sure you flush after with distilled water. The minerals in tap water will deposit on the walls of the radiator thus insulating the metal from the water reducing the cooling efficiency of the radiator.

I have reconsidered the dillution method above and figure it would take way too much distilled water to do a good job... i guess I will have to remove the alternator...

I don't like dillution either, I'm always afraid I won't get the mixture just right when I refill.

So am I correct to say the steps to flush your coolant system are as follows...I have never done this to a vehicle (kind of a "flushing your system for dummies"):

1.) loosen petcock (location unknown) and drain
2.) loosen engine block plugs (details unknown...remove alternator??)
3.) rinse using distilled water (should this be done w/ engine running?? closed or open petcock?? how long??)
4.) after rinse, fill w/ 50/50 mix

Sounds pretty easy? Did I miss anything?

Thanks for any assistance.

2001 Xterra SE,
You have the gist of it.

However, as Uzbad mentions, there isn't really a need to undo the block drain plugs.

What I do is as follows:
1.drain coolant, have heater set to hot to allow heater core to drain.
2.open cooling system bleed valve
3.fill system with distilled water only
4.close bleed valve
5.run up to temp and then allow to cool down
6.drain system again (this is your flush...but only with distilled water)
7.open bleed valve
8.fill with 50/50 mix of coolant
9.close bleed valve

Now, what kind of coolant to use?

There were some discussions in the past about people using the Nissan coolant...something like $18 a gallon . Others have used regular Prestone without incident. When I change out my coolant in the near future, I'm going to use Zerex Extreme 5/150. This is because of it's formulation, which is silicate, borate and phosphate free...all bad things to have in engines that aren't cast iron.

Bogatyr

Bogatyr--SWEET!! Thanks for your response...not to sound like an a$$, but where is the bleed valve?

2001 Silver Xterra SE,
If you have the 3.3 liter v6, it should be on a boss at the top of the intake manifold. On mine, there's a sticker that say "Never open when hot"...
If you have a 4 cylinder, I'm not sure where it is, but it should be somewhere near the top of the cooling system as well...
Bogatyr

Sorry Bogatyr but the flush you talk about is mearly a dillution as the engine block still holds a majority of the coolant.

Now if there was a way to get water into the engine block forcing the coolant there out and drain at the same time until it runs clear... doh I just realized after that you would have trouble getting the 50/50 you need...

There is no way around a good coolant change. You MUST remove the damn and most dispissed engine "plugs". If you don't have a lift get yourself a head-light so you can see the darn bolts.

EnderMyst,
Really? A "majority" of the coolant in the block? Isn't the lower radiator hose the lowest point in the system? If the air bleed bolt is opened and the lowest point in the system (the lower rad hose or the radiator drain plug) is opened, then most of the coolant should come out.
Bogatyr

Bogatyr, I am not possitive but since it sounds like you have done it, how much old coolant comes out with the first step you mentioned? Subtract that amount from the capacity, which is like 11 quarts and thats how much is left in the system.

EnderMyst,
I haven't changed the coolant yet on the Xterra, but every other system I've worked on was similar...having the lower radiator hose/radiator drain lower than the lowest cooling channel. Sure, there's a potential for some coolant to be left in the block, but I don't think it would be much...

You do have a good point on measuring things, heh, I'll see if I remember to do that when I get around to swapping this fluid out.

Bogatyr

The lower radiator hose leaves the radiator and rises halfway up before going into the engine so alot of coolant gets trapped in the engine block (like the reverse of the water trap on a toilet). Last time I changed the coolant I think it was only half the capacity that came out.

But as long as you change the coolant regularly and always use distilled water you shouldn't ever have to worry about deposits building up.

So...Does anyone have any specific details on step #2

The radiator drain is behind a rubber flap that you can see from below. It's held in place by 4 or 5 plastic pins on the rear of it, just push firmly up at the rear and they will pull out of the frame allowing the flap to drop down and expose the drain. Getting the pins back in place is a little tedious, but can be done. Start from the center and work to the outer ones.

As for the drain plugs and bleeder:



Brent

arent we forgetting the coolant system cleaner or does no one do that.

blackjackbender,
I wouldn't recommend the cleaner at all. Especially in an engine that has aluminum parts, it's not worth the risk. Just an interim fill with plain distilled water should do the trick. Remember, you should change out the coolant every two years anyway...the cleaner would be for cast iron blocks that have been neglected for years...
Bogatyr

Just did a drain and fill of the radiator.. what a mess.. and like they say coolant tastes sweet, YUK!

Anyway, just draining the radiator takes about 1.25 gallons and the total capacity is around 2.75 gallons so obviously ove half must be left in the engine block.

I did try to remove the engine block plugs but all I had was the 12-pt 14mm so I ended up stripping it before giving up. By the way, with a couple of ratchet extension (I used a 6" and a 2") along with one of those dual axis swivel extesions you can get at the left bank plug pretty easily... make sure you have a flashlight for your sanity.

Thise plugs are a pain to get out!!! I was able to get a socket on them, but I could not get them out (WUSS??!!) I think an air ratchet would've helped cuz they were on there pretty good...Anyways, since I was unable to remove plugs, I just drained radiator and replaced the coolant in the radiator...I assume I didn't get the proper mix (I went 50-50).