How to drain all the coolant?

Hey ... i want to flush out my coolant system, but my water is "hard" water ... well water with minerals in it. Good for your health, bad for your engine.

I want to do a complete flush of my system, but how can I do that with distilled water?

Make sense? If I use a hose to flush out the system, it will be full of hard water. I'd like to flush it out with the hose, then drain *all* of the fluid out of the block and refill with distilled water.

Any ideas?

There's probably an easier way, but after draining as much coolant as I could by removing the lower radiator hose, I thoroughly flushed out the block with a garden hose and then used a leaf blower to blow as much water out of the block as I could. Worked pretty well. I was replacing my radiator at the same time so I didn't have to worry about that, but I'd imagine the volume of the radiator is small enough that you could flush it with distilled water if you really wanted to...

Fill with distilled water and then drain it, repeat a few times and you will get out all the non-distilled water.

there's a drain plug on the driver side of the block, IIRC. It's slightly higher than the oil pan and takes some weird hex socket-- 5/16th, maybe....

Hook a water purifier to your garden hose?

If hard water is bad for your engine I feel sorry for every engine I've ever owned. Except for my 67 bug. I think its good.

Shorty said:

there's a drain plug on the driver side of the block, IIRC. It's slightly higher than the oil pan and takes some weird hex socket-- 5/16th, maybe....

Click to expand...

That's the easier way I was thinking of. I recall it being somewhat difficult to access though. Have you done it? Does it actually get all the fluid out of the block?

Shorty said:

there's a drain plug on the driver side of the block, IIRC. It's slightly higher than the oil pan and takes some weird hex socket-- 5/16th, maybe....

Click to expand...

Couldn't be that simple. It's a 5/16 SQUARE female. And it's tight!!!

On a Renix block, you can just remove the Coolant Temp Sensor. FWIW, those plugs and the sensor are mounted right at the lowest part of the water passages in the block. Therefore, I think the leaf blower or compressed air through the thermostat housing area would work well.

Good luck getting to that drain plug. Flush it then remove the water pump if you feel up to it. Jack the rear of the truck up a bit as the engine is leaned back to begin with.

lowrange2 said:

Hook a water purifier to your garden hose?

If hard water is bad for your engine I feel sorry for every engine I've ever owned. Except for my 67 bug. I think its good.

Click to expand...

LOL ... My first car ever was a red 67 bug. I learned to work on cars on that bug.

About the hard water ... it can't be good to build up a bunch of white mineral deposits in your cooling jackets. It's probably not a big deal, but this jeep is my special project ... I put a new motor in it a few years back, and want to treat it as good as possible.

A leaf blower or a shop vacuum might do the job. Be careful with compressed air, you don't want to rupture the heater core. 20 psi maximum.

I would just buy a number of 1 gallon jugs of filtered or distilled water.

Ok ... here's the plan:

• Add Prestone Radiator Flush and drive for a while.
• Park the jeep facing downhill
• Jack up rear if necessary
• Beer
• Flush entire system with hose
• Beer
• Shoot the breeze with neighbors who seem to materialize out of thin air every time your hood goes up:
  • Explain what you are doing
  • Listen carefully as they talk about how they would do it
  • Continue to do it your way, even if their way is better
• Flush heater core with hose:
  • Remove one end of both heater hoses, but keep them connected to firewall.
  • Press garden hose sprayer into top heater hose & flush (crap will come out of bottom hose)
  • Forget to hold the bottom hose away from you and spray crap all in your face, ears, nose, and t-shirt
  • After a few choice cuss words and time spent wondering why you don't just pay someone else to do the job wrong .... beer
  • Press garden hose sprayer into bottom heater hose & flush (crap will come out of top hose)
  • Repeat ad nauseum until heater hose water comes out clear
  • Use shop vac to get as much water out of heater core as possible
  • Put a funnel in top heater hose & pour in several gallons of distilled water.
  • Hard water will drain out of lower hose
• Beer
• Drain radiator
• Remove lower hose and drain block as best possible
• Use shop vac to get as much hard water out of block as possible
• Beer
• fill block with distilled water
• Drain block again
• Shop vac again
• Replace thermostat
• Put everything back together and fill with antifreeze and distilled water.

That should do a pretty good flush job.

The last time I did my '00, I used the following process:

1. Disconnect lower rad hose to drain old coolant.
2. Reconnect lower rad hose and fill system with garden hose.
3. Protect grill/bumper/etc. with plastric trash bags and then disconnect upper rad hose and route it over the grill (tied it in place w/ a string). Put a catch bin (old cat litter box) on the ground under the bumper.
4. Start the Jeep and let it come up to temp. As it starts pumping water out the top rad hose, keep the rad filled with the garden hose to provide a steady source of clean water. Once the discharge is clear, all the old collant has been removed. Turn off Jeep.
5. Disconnect lower rad hose to drain water.
6. Reconnect lower rad hose and fill with distilled water.
7. Start the Jeep again, but this time keep the rad topped off using distilled water. I think I ran 6 to 9 gallons through mine. Turn off Jeep.
8. Disconnect lower rad hose to drain water.
9. Reconnect lower rad hose and fill with a 50/50 mix of distilled water and antifreeze.

I also threw some radiator flush in there at some point and installed a new t-stat. Distilled water is cheap, don't be afraid to use a lot.

montanaman said:

Ok ... here's the plan:

• Add Prestone Radiator Flush and drive for a while.
• Park the jeep facing downhill
• Jack up rear if necessary
• Beer
• Flush entire system with hose
• Beer
• Shoot the breeze with neighbors who seem to materialize out of thin air every time your hood goes up:
  • Explain what you are doing
  • Listen carefully as they talk about how they would do it
  • Continue to do it your way, even if their way is better
• Flush heater core with hose:
  • Remove one end of both heater hoses, but keep them connected to firewall.
  • Press garden hose sprayer into top heater hose & flush (crap will come out of bottom hose)
  • Forget to hold the bottom hose away from you and spray crap all in your face, ears, nose, and t-shirt
  • After a few choice cuss words and time spent wondering why you don't just pay someone else to do the job wrong .... beer
  • Press garden hose sprayer into bottom heater hose & flush (crap will come out of top hose)
  • Repeat ad nauseum until heater hose water comes out clear
  • Use shop vac to get as much water out of heater core as possible
  • Put a funnel in top heater hose & pour in several gallons of distilled water.
  • Hard water will drain out of lower hose
• Beer
• Drain radiator
• Remove lower hose and drain block as best possible
• Use shop vac to get as much hard water out of block as possible
• Beer
• fill block with distilled water
• Drain block again
• Shop vac again
• Replace thermostat
• Put everything back together and fill with antifreeze and distilled water.

That should do a pretty good flush job.

Click to expand...

Somewhere in there you might want to have a beer or two. :laugh2:

Scorpion8 said:

Somewhere in there you might want to have a beer or two. :laugh2:

Click to expand...

Beer must have some internal lubricants, because it makes everything go so much smoother :thumbup:

And the knuckles don't hurt until the next day.

Be careful sometimes you can end up spraying water under your hood in the process of flushing, like if a hose disconnects. I did that and degreased the spring mechanism attached to the throttle cable with out noticing, a few months later I got a stuck gas pedal, it was a 1 minute fix, I just added more grease to the spring and mechanism and it was fine.

Just thought I throw that out there.

Good point.