Difficulty
Moderate
Steps
10
Time Required
1 hour
Sections
1
- thermostat
- 10 steps
Flags
2
In Progress
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BackChevrolet Duramax 6.6 LB7
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What you need
Step 1
Drain Some Coolant
- Start by making sure the engine is cool. If the engine is hot let it sit till it has cooled off. Insert a clean bucket under the drain on the passenger side of the radiator. Turning the petcock will allow coolant to flow out. Drain about 2-2.5 gallons of coolant. This process can be sped up by removing the pressure cap
Start by making sure the engine is cool. If the engine is hot let it sit till it has cooled off. Insert a clean bucket under the drain on the passenger side of the radiator. Turning the petcock will allow coolant to flow out. Drain about 2-2.5 gallons of coolant. This process can be sped up by removing the pressure cap
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Step 2
Removing the serpentine belt
- Use a ratchet with a 1/2in anvil to pull the tensioner back allowing the belt to be slipped off the alternator.
Use a ratchet with a 1/2in anvil to pull the tensioner back allowing the belt to be slipped off the alternator.
Step 3
Removing the alternator
- Remove the negative cables from both batteries. Remove the electrical connections off the alternator. A small flathead screwdriver can aid in this. Use caution to not break the connectors. Use a socket to remove the positive cable off the back of the alternator. Finally remove the mounting bolts and pull off the alternator.
Remove the negative cables from both batteries. Remove the electrical connections off the alternator. A small flathead screwdriver can aid in this. Use caution to not break the connectors. Use a socket to remove the positive cable off the back of the alternator. Finally remove the mounting bolts and pull off the alternator.
Step 4
Removing the A/C condensor
- Start by removing the electrical connection from the condensor. Use a socket to remove the mounting bolts from the condensor. Now that the condensor is loose. Flip it back into the engine bay. Doing this will allow for the A/C lines to not be disconnected simplifing the repair.
Start by removing the electrical connection from the condensor. Use a socket to remove the mounting bolts from the condensor. Now that the condensor is loose. Flip it back into the engine bay. Doing this will allow for the A/C lines to not be disconnected simplifing the repair.
Step 5
Removing the upper coolant pipe
- Remove the bolts from the pipe using a socket. Pull the pipe rearwards to remove the pipe from the thermostat housing. This may require some force. When reassembling a very light amount of grease or other lubricant can be used to lubricate the o-ring on the pipe for easier installation
Remove the bolts from the pipe using a socket. Pull the pipe rearwards to remove the pipe from the thermostat housing. This may require some force. When reassembling a very light amount of grease or other lubricant can be used to lubricate the o-ring on the pipe for easier installation
Step 6
Removing the thermostat housing
- Use your sockets to remove the bolts from the thermostat housing. Remove the housing and inspect for any cracks or damage.
Use your sockets to remove the bolts from the thermostat housing. Remove the housing and inspect for any cracks or damage.
Step 7
Removing the thermostats
- Remove the thermostats. They maybe stuck if this is the case use the screwdriver to pop them out. make sure the seals are not stuck in the lower part of the housing.
Remove the thermostats. They maybe stuck if this is the case use the screwdriver to pop them out. make sure the seals are not stuck in the lower part of the housing.
Step 8
Preparing for reassembly
- Check to ensure no debris has entered into the bottom of the housing.The new thermostats should have the new seals installed on the bottom. If not simply install the seals into the bottom of the housing and place the thermostats on top. The thermostat with 2 small holes in it goes into the rear spot.
Check to ensure no debris has entered into the bottom of the housing.The new thermostats should have the new seals installed on the bottom. If not simply install the seals into the bottom of the housing and place the thermostats on top. The thermostat with 2 small holes in it goes into the rear spot.
Step 9
Reassembly
- Congratulations you have successfully removed the thermostats. For reassembly simply follow these steps in reverse order.
Congratulations you have successfully removed the thermostats. For reassembly simply follow these steps in reverse order.
Step 10
Refilling the coolant
- Once fully reassembled Remove the bleeder screw on top of the housing. Slowly refill the resevoir with coolant until it starts coming out of the bleeder. Reinstall bleeder and run the engine for a short time. Check for proper coolant level and add coolant if necessary. Inspect to ensure there are no leaks.
Once fully reassembled Remove the bleeder screw on top of the housing. Slowly refill the resevoir with coolant until it starts coming out of the bleeder. Reinstall bleeder and run the engine for a short time. Check for proper coolant level and add coolant if necessary. Inspect to ensure there are no leaks.
To reassemble your device, follow these instructions in reverse order.
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Chase Malone
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