Till I get my Shop Manual.Anyone have the Radiator Flush procedure for a 96'?

 

Can't believe you didn't get a single response

Here's a ride to the top

seeya

 

Must be too elementary. I asked because I think the Reverse Flow of my LT4 is flushed a little differently.I'll take off the bottom Radiator hose to drain..Take off the knock sensors to drain the block maybe stick a hose in the Rad. hose to flush?

Thanx

 

Remove the radiator cap on the expansion tank. Drain the radiator using the petcock (plastic so be careful with tools!!) and remove both knock sensors. The knock sensors are sort of a PITA to remove as they have a shield and they take a 21 or 22mm socket to remove. While removing the lower hose is not really necessary, it may be a good time to replace both the upper and lower radiator hoses if they are original. I re-used the factory spring clamps on my 92 two years ago and they are holding fine.

You can run a garden hose thru the upper tank to help remove any junk but if the old coolant comes out clean looking, you should be OK with just a coolant refill. Remove the overflow tank (in right side wheelwell) from the car and drain and clean it. Re-install when you are ready to do the refill.

Your 96 uses Dexcool so refill with that. It will take 2 gallons of coolant and about two gallons of water for a 50-50 mix which is good for -37 degrees or so. Use distilled water from a grocery store; it will cost under a buck a gallon so get 3 gallons.

With everything buttoned up, open the bleed valve on the thermostat housing and throttle body (the 96 may only have a single bleed valve but it needs to be open in any event) and pour in the 2 gallons of coolant. Then begin adding the water. When a steady stream of liquid comes out of the bleed valve, (use a towel or aluminum foil to keep water off the Opti!!) close it and continue filling to the lip of the expansion tank. Start the motor and let the temp come up to where the thermostat opens. Run the engine about 1000-1200RPM for this.

Once the 'stat opens, continue filling so that the coolant level is just below the rim of the tank where the cap sits. Watch the water temp closely; if it gets above 230-240 stop the motor and let it cool and then start again.

Once the coolant temp is at a constant level, install the pressure cap. Install the overflow tank and fill with a 50-50 mix of coolant to the "Cold" line. Do not do any full throttle appliacations until the engine has gone thru 3 cycles where the coolant goes to operating temp and then cools off to cold. (this is from my 92 service manual).

 

Thanx George.

I'm gonna do this tomorrow.

Appreciate your help.

Dennis

 

Actually, if you have a Shop Vac with reverse thrust/blower capability you don't have to remove the knock sensors.

Remove the radiator cap on the expansion tank. Drain the radiator using the petcock (plastic so be careful with tools!!) and then place the hose over the coolant expansion tank.

The forced air does an excellent job of pushing the coolant out of the block AND heater core without having to remove those often troublesome sensors.

 

Excellent Idea.

Should I take out the Thermostat??

 

Also, How do I get the Heater Valve to stay open so it will drain??

 

What you think?

 

Here's my opinion on the radiator flush based on my experience.

My '96 ran "normal" temperatures (205 max with fan reprogramming, 220 before that... A/C on at 90 degrees ambient temp... idle traffic.) at 106K with the original radiator (Dex-Cool replaced at 93K). That radiator developed some cracks on the plastic end-tanks that allowed some minor coolant weep.

I replaced the radiator with a new OEM unit and guess what.... no difference in temps.

So as for flushing, I'd say don't worry about it and just replace the coolant.

I would recommend the use of distilled water and the recommended mix ratio provided by the coolant manufacturer.

 

Just switch your climate control to HEAT and turn up the temp control to max. Let engine reach operating temp and that will do it. You do not need to remove your thermostat to flush-n-fill.