What coolant should I use?

[SnowDrifter]

So you're saying that I don't need to remove the thermostat to do the flush? I tried to pull it out of the housing, but it seems pretty stuck in there.

Also, how do you know when to stop filling the upper rad hose? I forgot to remove the thermostat at this point, but I put about 1.5gal water in the hose and then I started up the car. After a little bit, I started to see the low coolant message so I freaked out and added a 1/2 gal at the reservoir. Saw light smoking from the front of the engine after letting it run 5 mins.

correct


The heater hose outlets are right next to the thermostat. Remove those, you'll drain whatever you'd get from the thermostat


For the radiator hose: take the cap off your reservoir, tilt the rad hose up, fill until it dribbles out somewhere. Reconnect, then fill from the reservoir as per normal

If you've never bled air out of a cooling system before, the methodology is this:

- Fill from the upper rad hose (specific to our vehicles this isn't universal)
- top up the reservoir
- Leave the cap off and start the car
- add coolant as needed to the reservoir
- As the engine warms up a bit, give the thing a couple sharp revs
- Verify you have interior heat. Newer vehicles like ours control heat by changing air flow, not coolant flow, so ya don't need to blast it. High heat just makes it take longer to warm up.
- check coolant level again. If air burped out of the heater cores, you'll
- toss the cap back on and either let it idle, or (preferrably) take it for a drive until the thermostat opens. I like to toss the gearbox in "3" to keep the revs up a touch and help ensure any small bubbles in strange spots are pushed out. tbh these rigs don't really depend on a thermostat opening to bleed air so this step isn't needed, but I like to do it as a final validation.
- check level again when you park
- when the vehicle cools down the following morning, you'll probably have to add a splash as everything cools and contracts



For the distilled water flushes, skip the driving / thermostat opening part. Work with a warm engine so you can feel when clean DiH2O has made it to the heater core. But you don't need to go further than that. Fill it, get some air out, blip the throttle till you have heat, drain, go again. Shouldn't take you more than 3 maybe 4 minutes per cycle.

 

[89Suburban]

Good stuff.

 

[JamesLond]

OK, what's happening here?

I'm now seeing smoke coming from the exhaust. Also, when I look closer at it, it looks like puddling water.

On my last flush I filled water from the top hose until water spilled out from the reservoir. I then ran the car 6 or 7 minutes with the the heat on high. That's when I started to see the light smoke.

I don't think I noticed any smoking on the other flushes I did. I did notice that when I tried to top off the coolant reservoir with water after filling up the top rad hose, it would never really stay full.

 

[SnowDrifter]

C8H18 + O2 -> CO2 + H2O

Water is a byproduct of combustion

Idle doesn't really dump enough heat in the exhaust to keep it hot enough to prevent the water from precipitating out in the form of steam.

You'll probably be topping it up for a couple minutes before the air works its way all out


Finish your tasks, add coolant, bleed it, then go drive it on the freeway for 9 or 10 miles. Won't be any moisture left

*and I will smack you for using tap water*

 

[JamesLond]

I'm still concerned about this.I got my water pump off and for some reason all my lower pump bolts were blackened. The two clean ones were highest up.




Here are pics of the driver and pass side head coolant openings also.

 

[SnowDrifter]

Looks about par for coolant that's been run longer than the service interval

Take a brillo pad and, by hand, clean it up.

I also feel that as we post more and more, there's quite a bit of info missing from this post.

From a removed water pump, to concerns about water out the exhaust

What's going on chief?

 

[89Suburban]

I'm still concerned about this.I got my water pump off and for some reason all my lower pump bolts were blackened. The two clean ones were highest up.

View attachment 366517


Here are pics of the driver and pass side head coolant openings also.

View attachment 366519View attachment 366520

I've seen worse.

 

[JamesLond]

Looks about par for coolant that's been run longer than the service interval

Take a brillo pad and, by hand, clean it up.

I also feel that as we post more and more, there's quite a bit of info missing from this post.

From a removed water pump, to concerns about water out the exhaust

What's going on chief?

As per your recommendation in my other thread, I opted to replace my pump gaskets. This is what I'm going through to do it.

Oh yes, I actually did use distilled water when I was flushing.

 

[MassHoe04]

Just curious... What do dealers use for coolant?

In all the garages I have been in, I haven't seen anything labeled as a distilled water supply.
Just a hose hooked to a spigot on the wall, which gets used for everything.

Do dealers use pre-mixed 50/50 from bulk supply tanks?
I would be surprised, if they were mixing on the fly for each vehicle.

I have never spotted anything in any service bay, labeled distilled water. No hoses, tanks or jugs. I haven't seen any delivery tankers trucking in new supplies of distilled water either.

Are they just using reverse osmosis filters in the shop to filter out impurities in the water?

Mom and pop shops are probably not likely to even have a filter. Probably just a garden hose to a tap.

Anybody have any "behind the scenes" insights?

 

[exp500]

^^^^^^^^^
You pays your money, you takes your chances!