I want to Flush & Replace the Engine Coolant in my 3.9 liter engine.
Per the Haynes Manual I have, the Radiator Drain is at the Left Lower side of the Radiator. (See picture 33.3)
I found it, the external blade was Vertical, I disconnected the little hose and turned the Drain CCW 90°, so the blade is horizontal.
Nothing happened. I poked and twisted a stiff wire in the Drain Orifice, thinking it might be clogged, and still nothing.
The wire doesn't go beyond the Drain-****.
What am I not doing, or doing wrong?
Do I need to pull on the Drain?

Secondly, the Manual says that I need to remove two Bolts on either side of the Lower Front Block and drain those also.
The picture 33.4 shows the one on the Driver's Side, and I found both, but the one on the Pass. Side is BEHIND the Motor Mount. That''s Nuts!!!

Any help getting the Drain to work will be Greatly appreciated.

Thanks
Rich

 

They sell inexpensive flush kits that tap into the heater hose. It'll also flush water through the heater core as opposed to just the radiator and you don't need to remove the thermostat.

On my drain plug you turn it 1/4 turn and pull.

Have you ever pulled the block drains before? After 12 years they may be corroded in place.

 

Thanks Dan:
So I did right, turning the Drain 90° CCW and I just need to pull on it with a Pliers? I thought it was something simple like that but thought I should ask before going Gorilla and maybe breaking it and having to replace the Radiator.

The tag in the Engine Bay indicates that the Automatic Trans. and the Cooling System were flushed in July '08 @ 85K miles.
It has 130K miles on it now.
I bought the truck right at 2 years ago from a friend who had it for 5 years.
It was too big for him and he wanted an '02 Kia Reo. So I bought it for him and he gave me the truck.
Other than drive it around my farm property I haven't been able to drive it because of a DUI until this past August.

The Prestone Heater Hose Flush Kit is what I've always used in my vehicles until I quit wrenching in '91.
The Prestone Kit I'm used to, Back Flushed the system out through the Cap Hole on the Radiators.
But on this truck the Radiator Cap is in the Hose, over the Engine, close to the Throttle Body.
The configuration doesn't appear capable of Back Flushing unless I can figure a way to keep the solution from flooding all over the Intake Manifold.

Now that I think of it, I'm sure I have left over Kit Parts, including the Goose Neck that fits in the Cap Hole, and I can slip a Hose over it and keep the Engine dry.

I just replaced that Top Hose because it had burst and it was easier to get the Thermostat/Hose Coupler off than it was to remove the Hose from the Coupler.

Dan, thanks for the info. I'll post back the outcome of this little adventure.

 

Drain ***** should turn 1/4 turn and pull down to open.But with were they are located not uncommon for them to get junk in there.

 

I made up an extension from a piece of old washing machine drain hose, the diameter is perfect to fit on the goose neck. Makes for a much neater, and easier, flush.

 

Hit a Snag...
The Heater Hose Return Pipe, that fits into the Water Pump is rusted a bit and has an ever so slight Wet Spot on it.
I put my finger the spot and sure enough it's wet.
Any suggestions for getting that Return Pipe out without damaging the Water Pump?

The Serpentine Belt Ribs are full of small cracks too, so that replacement is in the cards also.

 

There's a o-ring on the tube. If you remove that bolt it should pull out, may need some persuasion. You can get a new tube at your parts store and an o-ring.

Lube up the o-ring before installing, use some antifreeze.

 

That pipe has 1 bolt holding it in. I used a pair of channellocks and twisted while pulling. It is a Beotch to get out. Also make sure you Get a new o ring for the new pipe


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I got the new Return Tube from NAPA which has an O-ring and a can of PB Blaster.
When I got home I sprayed the Tube with it and looking closely saw that there was a rotted O-ring on the old Tube where it meets the Water Pump. I picked it away with a small screwdriver and sprayed it again.

Gauging by the size of the Tube, I decided that I didn't have the proper sized "T" part, of the Flush Kit remnants I've accumulated, to do the Flush. So I bought a smaller NAPA Kit that included everything I need except the "Radiator Cap" Goose Neck.

My plan of attack is as follows:
1. Drain the system and replace the Return Tube.
2. Add Prestone Flush fluid and water, and follow the directions, excluding re-filling with Anti-freeze.
3. Remove the thermostat and Back-flush the system with water with-out the Engine running and drain.
4. Disconnect the the Heater Hoses and fill the Heater Core with Prestone Flush fluid, let it sit and Back-flush Compressed Air.
5. After rinsing the Heater Core with water, re-connect it to the system and fill with 50/50 Anti-freeze solution.

 

Ive never used the drain plug always just pulled off the lower rad hose much faster.