Should I fill the coolant reservoir after coolant flush?

[dockdoc]

‘02 TJ 4.0.

I looked in my reservoir recently and was appalled at all the gunk. I think when I had the block plugs replaced recently they put in the wrong coolant.

I’m following this thread https://wranglertjforum.com/threads/how-to-flush-the-cooling-system-on-your-jeep-wrangler-tj.1737/

Although I’m not doing the tee in the heater core line, I don’t see the point of it.

So far I’ve drained the radiator, flushed it with distilled, could not get it looking clear so I added a bottle of Prestone coolant cleaner and will be driving the vehicle around for a couple hours to let that do its thing before I drain that, drain the block, and then refill with zerex G05.

Question is pretty basic: what do I do about the reservoir? I understand topping off the radiator, but should I add a 50/50 mix into the expansion tank directly until it reaches the fill line as well? Or do I leave it empty? And any suggestions on cleaning it? There’s an impressive amount of gunk on the walls, but not like I can get a brush in there or anything.

Thanks, appreciate any tips!

 

[Chris]

Add the coolant mix to the reservoir until it reaches the fill line, yes.

As far as cleaning it goes, you can remove the bottle and use some high pressure soap and water to clean the inside. That or some degreaser would work as well as long as you rinse it out with soap and water after.

 

[red02tj]

Add in a scoop of ice cubes and shake if it’s really dirty.

 

[Camdenst]

Add in a scoop of ice cubes and shake if it’s really dirty.

That’s also great for coffee pots

 

[cpwolf]

I wouldn’t just use the Prestone.

If you’re doing all of this, I’d put Thermocure in there and run around town, maybe leave it in over night.

Then I’d drain it from the radiator drain onky. Then pull the thermostat, leave it out, and put the housing back. Fill with distilled only, run it 4-5 minutes or less.

Drain it, and the block plug. Repeat until it comes out clear (mostly).

Then put a new Thermostat, and fill 50/50 and fill the overflow 50/50 Zerex as well.

I did all that and now it’s always wanting to run under 210, even last August in Texas with AC on.