more t-stat stuff
06-07-2018, 07:04 PM
#31
Senior Member
Join Date: 04-03-2018
Location: Florida
Posts: 247
TSB continued
Prestone used to make a cleaner for GM P/N 12346500.
It was also sold under Prestone P/N AS100 Heavy Duty Cooling System Cleaner
GM TSB and Instructions #99-06-02-012D (Online or at a GM dealer)
It is not made anymore but these are the components.
9 dry oz of Oxalic Acid (DAP Wood Bleach)
2 dry oz of Sodium Carbonate (Arm & Hammer Super Washing Soda)[/QUOTE]
Apparently Permatex Heavy Duty Aluminum Radiator Flush if you don't like wood bleach.
Personally, I do a serious flush whenever I get a used car and then every 2 years drop, rinse with water and fill with new coolant, no matter what the label says. Twenty bucks and an hour is time and money well spent.
Good luck with whatever route you choose.
Under no circumstances should the neutralizer be left in the cooling system for any longer than ten minutes once the vehicle has reached operating temperature (thermostat open). The neutralizer is corrosive to aluminum and will damage system components if it is left in the cooling system for longer than ten minutes.
Pour the mixture from the step above into the radiator.
Completely refill the cooling system with warm to hot water through the "T". When the radiator is full, install the radiator cap to the safety catch. Continue to fill until the overflow reservoir is filled to the hot line on the reservoir.
Remove the fill hose and install the cap on the "T" and the radiator fully.
Important: It is imperative that all air pockets have been removed in order for the procedure to be effective.
Start the engine. After engine speed stabilizes, reinstall the dime between the closed throttle stop and the screw. With the A/C on, bring the cooling system back to normal operating temperature and follow the directions on the can.
Turn off the engine.
Remove the dime from the closed throttle stop and the screw.
Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the radiator cap while the engine is hot and pressure is high will cause the solution to boil instantaneously - possibly with explosive force - spewing the solution over the engine, fenders and the person removing the cap.
Drain the cooling system, following the procedure listed in Step 24 above.
Do not close the radiator drain. Leave it open.
Disconnect the upper radiator hose from the radiator. Properly position the hose, so the accessory drive belt or any pulley/belt cannot touch the hose.
Attach a garden hose to the "T" of the flush and fill kit. Turn on the water and back flush the cooling system for at least two minutes after the water runs clear.
Start the engine and continue back flushing the cooling system for five additional minutes.
Turn the engine "OFF".
Turn the water "OFF".
Close the radiator drain.
Important: If the repair is a Procedure A, go to Step 40.
If the repair is a Procedure B, remove the radiator and have it recorded and steam clean the end tanks. After reinstalling the radiator, continue to Step 40.
Remove the air cleaner housing and tube assembly from the throttle body.
Remove the two nuts holding the throttle cable bracket to the throttle body and position the bracket and the cables out of the way.
Remove the thermostat.
Remove the previously installed flush kit "T" and hose. Save for future use on other vehicles.
Install the heater inlet hose to the intake manifold and secure with the original spring clamp.
Inspect the thermostat opening and cover for foreign material. Clean if necessary.
Remove the left lower water pump crossover bolt to drain the left side of the block and the left cylinder head.
Install sealant to the bolt threads, using GM P/N 12346004 (Canada GM P/N 10953480), or equivalent and reinstall the water pump crossover bolt.
Tighten
Tighten the bolt to 41 Nˇm (30 lb ft).
If available, use coolant exchanger Pro-Fill, Power Flush, or equivalent to fill the system with 50/50 DEX-COOLŽ coolant. If a coolant exchanger is not available, proceed to the next step now. Follow the manufacturer's instructions for system fill/coolant exchange. If you are using coolant exchange equipment, you will need to install a new thermostat, GM P/N 12563335 and top off the system with clean drinkable water prior to exchanging. After exchanging, install the upper radiator hose and clean out the coolant recovery bottle. Proceed to Step 56.
Pour 5.6784 L (6 qts) of 100% (not pre-mixed) DEX-COOLŽ coolant into a clean container.
Using a clean funnel, pour as much of the 100% DEX-COOLŽ coolant that you can into the engine through the thermostat opening.
Install a new thermostat, GM P/N 12563335.
Tighten
Tighten the bolt to the specified torque of 19 Nˇm (14 lb ft).
Hold the upper radiator hose in the straight up position and pour 0.473 L (1 pint) of the 100% DEX-COOLŽ coolant into the hose.
Install the upper radiator hose to the radiator and properly position the clamp.
Flush the coolant recovery bottle thoroughly.
Complete the fill of the cooling system with the balance of the 5.7 L (6 qt) of 100% DEX-COOLŽ coolant and top off with plain water. If the water is not drinkable, do not use. Water must be clean and fresh.
Important: The second new radiator cap must be installed at this point of the procedure. It is possible that small contaminants may have become lodged in portions of the first cap during the cleaning procedure.
Clean the radiator cap sealing surfaces on the radiator. Install the radiator cap, GM P/N 15075565.
Important: It is imperative that all air pockets have been removed in order for the cooling system to function properly.
Run the engine to operating temperature with the air conditioning in the maximum cool position for ten minutes.
Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the radiator cap while the engine is hot and pressure is high will cause the solution to boil instantaneously - possibly with explosive force - spewing the solution over the engine, fenders and the person removing the cap. Under some conditions, the engine coolant is combustible.
Turn the engine "OFF" and let it cool.
Check the coolant concentration for a 50/50 mix, using refractometer J 26568 (Centigrade scale) or J 23688 (Fahrenheit scale). Follow the manufacturer's directions for using the coolant tester. Unless your coolant tester has a provision for temperature correction, it is imperative that the correct coolant temperature is achieved when testing the coolant. If the coolant is warmer or cooler, the reading may be incorrect.
Top off the radiator and fill the coolant recovery bottle to 2.54 cm (1 in) above the full hot mark on the coolant reservoir. Add the appropriate coolant mixture to come to a 50/50 mix of the DEX-COOLŽ coolant.
Important: To assure intended system performance, inform the customer that the cooling system MUST be maintained in a completely full condition.
Parts Information
Part Number
Description
12346500
PrestoneŽ Heavy Duty Cooling System Cleaner
12563335
Thermostat
15075565
Radiator Cap
Parts are currently available from GMSPO. AFAIK, GM 12346500 (aka Prestone AS100) no longer available ... exchange woodbleach & washing soda
Pour the mixture from the step above into the radiator.
Completely refill the cooling system with warm to hot water through the "T". When the radiator is full, install the radiator cap to the safety catch. Continue to fill until the overflow reservoir is filled to the hot line on the reservoir.
Remove the fill hose and install the cap on the "T" and the radiator fully.
Important: It is imperative that all air pockets have been removed in order for the procedure to be effective.
Start the engine. After engine speed stabilizes, reinstall the dime between the closed throttle stop and the screw. With the A/C on, bring the cooling system back to normal operating temperature and follow the directions on the can.
Turn off the engine.
Remove the dime from the closed throttle stop and the screw.
Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the radiator cap while the engine is hot and pressure is high will cause the solution to boil instantaneously - possibly with explosive force - spewing the solution over the engine, fenders and the person removing the cap.
Drain the cooling system, following the procedure listed in Step 24 above.
Do not close the radiator drain. Leave it open.
Disconnect the upper radiator hose from the radiator. Properly position the hose, so the accessory drive belt or any pulley/belt cannot touch the hose.
Attach a garden hose to the "T" of the flush and fill kit. Turn on the water and back flush the cooling system for at least two minutes after the water runs clear.
Start the engine and continue back flushing the cooling system for five additional minutes.
Turn the engine "OFF".
Turn the water "OFF".
Close the radiator drain.
Important: If the repair is a Procedure A, go to Step 40.
If the repair is a Procedure B, remove the radiator and have it recorded and steam clean the end tanks. After reinstalling the radiator, continue to Step 40.
Remove the air cleaner housing and tube assembly from the throttle body.
Remove the two nuts holding the throttle cable bracket to the throttle body and position the bracket and the cables out of the way.
Remove the thermostat.
Remove the previously installed flush kit "T" and hose. Save for future use on other vehicles.
Install the heater inlet hose to the intake manifold and secure with the original spring clamp.
Inspect the thermostat opening and cover for foreign material. Clean if necessary.
Remove the left lower water pump crossover bolt to drain the left side of the block and the left cylinder head.
Install sealant to the bolt threads, using GM P/N 12346004 (Canada GM P/N 10953480), or equivalent and reinstall the water pump crossover bolt.
Tighten
Tighten the bolt to 41 Nˇm (30 lb ft).
If available, use coolant exchanger Pro-Fill, Power Flush, or equivalent to fill the system with 50/50 DEX-COOLŽ coolant. If a coolant exchanger is not available, proceed to the next step now. Follow the manufacturer's instructions for system fill/coolant exchange. If you are using coolant exchange equipment, you will need to install a new thermostat, GM P/N 12563335 and top off the system with clean drinkable water prior to exchanging. After exchanging, install the upper radiator hose and clean out the coolant recovery bottle. Proceed to Step 56.
Pour 5.6784 L (6 qts) of 100% (not pre-mixed) DEX-COOLŽ coolant into a clean container.
Using a clean funnel, pour as much of the 100% DEX-COOLŽ coolant that you can into the engine through the thermostat opening.
Install a new thermostat, GM P/N 12563335.
Tighten
Tighten the bolt to the specified torque of 19 Nˇm (14 lb ft).
Hold the upper radiator hose in the straight up position and pour 0.473 L (1 pint) of the 100% DEX-COOLŽ coolant into the hose.
Install the upper radiator hose to the radiator and properly position the clamp.
Flush the coolant recovery bottle thoroughly.
Complete the fill of the cooling system with the balance of the 5.7 L (6 qt) of 100% DEX-COOLŽ coolant and top off with plain water. If the water is not drinkable, do not use. Water must be clean and fresh.
Important: The second new radiator cap must be installed at this point of the procedure. It is possible that small contaminants may have become lodged in portions of the first cap during the cleaning procedure.
Clean the radiator cap sealing surfaces on the radiator. Install the radiator cap, GM P/N 15075565.
Important: It is imperative that all air pockets have been removed in order for the cooling system to function properly.
Run the engine to operating temperature with the air conditioning in the maximum cool position for ten minutes.
Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the radiator cap while the engine is hot and pressure is high will cause the solution to boil instantaneously - possibly with explosive force - spewing the solution over the engine, fenders and the person removing the cap. Under some conditions, the engine coolant is combustible.
Turn the engine "OFF" and let it cool.
Check the coolant concentration for a 50/50 mix, using refractometer J 26568 (Centigrade scale) or J 23688 (Fahrenheit scale). Follow the manufacturer's directions for using the coolant tester. Unless your coolant tester has a provision for temperature correction, it is imperative that the correct coolant temperature is achieved when testing the coolant. If the coolant is warmer or cooler, the reading may be incorrect.
Top off the radiator and fill the coolant recovery bottle to 2.54 cm (1 in) above the full hot mark on the coolant reservoir. Add the appropriate coolant mixture to come to a 50/50 mix of the DEX-COOLŽ coolant.
Important: To assure intended system performance, inform the customer that the cooling system MUST be maintained in a completely full condition.
Parts Information
Part Number
Description
12346500
PrestoneŽ Heavy Duty Cooling System Cleaner
12563335
Thermostat
15075565
Radiator Cap
Parts are currently available from GMSPO. AFAIK, GM 12346500 (aka Prestone AS100) no longer available ... exchange woodbleach & washing soda
It was also sold under Prestone P/N AS100 Heavy Duty Cooling System Cleaner
GM TSB and Instructions #99-06-02-012D (Online or at a GM dealer)
It is not made anymore but these are the components.
9 dry oz of Oxalic Acid (DAP Wood Bleach)
2 dry oz of Sodium Carbonate (Arm & Hammer Super Washing Soda)[/QUOTE]
Apparently Permatex Heavy Duty Aluminum Radiator Flush if you don't like wood bleach.
Personally, I do a serious flush whenever I get a used car and then every 2 years drop, rinse with water and fill with new coolant, no matter what the label says. Twenty bucks and an hour is time and money well spent.
Good luck with whatever route you choose.
06-10-2018, 05:47 PM
#33
New Member
Thread Starter
Join Date: 05-25-2018
Location: North Central Kansas
Posts: 12
Well, the radiator didn't get here yet. Gives me time to get the correct tool to remove the oil cooler lines. Also, someone mentioned checking the trans oil level is not like checking a dipstick. So what do I need to do and where does a person add fluid if low? I looked under the hood and didn't see a fill location. I guess my next stop is the How To section.
06-24-2018, 07:58 AM
#35
New Member
Thread Starter
Join Date: 05-25-2018
Location: North Central Kansas
Posts: 12
Well, I'm back. To recap, on the hwy the car runs warm (212-218) and in town (228-240). One interesting note my wife reported that on the hwy on a cool day, outside air temp in mid 80's, the car would run hot (220-228) and on a hot day 95-98 outside air temp, the car would run cooler (204 208). This is at 65 mph on the hwy and no ac running. And in town driving temps would spike to 238 and sometimes 242 briefly.
So, yesterday I replaced the thermostat with a GM ACDelco unit, replaced the radiator, pressure cap and new DexCool coolant. Burped the system once and went for a test drive. NO change. I just went around a long block in our neighborhood and temps got into the 240 range. Really disappointed. Took car home and drove up on the run up ramps I had made. Opened hood and checked for leaks, none found. Restarted car temp was 224, so I turned on the AC to get fan running. That brought the temp down to 220 after about 1 1/2 minutes. So then I ran the engine speed up to about 2500 rpm and that started lowering the temp. Finally got the temp down to 204. Not sure what to make of all this. Your thoughts/ideas???
So, yesterday I replaced the thermostat with a GM ACDelco unit, replaced the radiator, pressure cap and new DexCool coolant. Burped the system once and went for a test drive. NO change. I just went around a long block in our neighborhood and temps got into the 240 range. Really disappointed. Took car home and drove up on the run up ramps I had made. Opened hood and checked for leaks, none found. Restarted car temp was 224, so I turned on the AC to get fan running. That brought the temp down to 220 after about 1 1/2 minutes. So then I ran the engine speed up to about 2500 rpm and that started lowering the temp. Finally got the temp down to 204. Not sure what to make of all this. Your thoughts/ideas???
06-24-2018, 08:57 AM
#38
Administrator
Join Date: 10-13-2011
Location: Welland,Ont Canada
Posts: 37,698
I suggest removing the valve cover to check timing chain tension, and the front engine cover the inspect the water pump / balance shaft chain guides.
You might as well change them while you’re in there and the water pump.
If you choose to just change the water pump, there’s nifty tools to hold the water pump sprocket.
You might as well change them while you’re in there and the water pump.
If you choose to just change the water pump, there’s nifty tools to hold the water pump sprocket.
07-20-2018, 08:27 AM
#39
New Member
Thread Starter
Join Date: 05-25-2018
Location: North Central Kansas
Posts: 12
It's been awhile since I last commented here. After monitoring the car for awhile now, we are seeing the following, on hot days with outside air temps above 95 degrees the car runs relative cool with dashboard readings of 195-200 degrees. On cool days with outside temps in the 85-90 degree range, the car temps are 204 to 210 and a few 214 readings. I do believe all the work, radiator, t-stat, radiator pressure cap and coolant replacement have helped. I am really confused with the car running hotter on cooler days and running cooler on hotter days. Anyone have ideas on that one? I am thinking I would like to try a water pump replacement. Does anyone have a link on where to get that special tool needed to hold the gears/chain or what in alignment?