OldManKamps
New member
Hey there, I just did my first coolant flush and I found that the information available was actually quite vague for these trucks!
So I decided to do my own writeup. This is my first writeup for anything so if anyone has any other tips that are helpful, feel free to add them!
A coolant flush is a drain/dilution of the coolant in the system and a replacement of that coolant. A traditional radiator flush only drains what's in the radiator and not whats in the engine (I think).
I wanted to do a full coolant flush because my bozo PO used green coolant instead of the Toyota Red which these trucks need.
The first step is to drain. I found that the rad and engine drain much better if the engine is hot. Now BE CAREFUL, the coolant coming out of the rad is 90 degrees Celsius. The good thing is that the drain is engineered in such a way that you can easily not get burned.
1. Get down on your side/back under the truck and from the "facing the truck" perspective, there is a little white plastic "petcock" or drain plug on the left or passenger side facing the rear. The plug unthreads counterclockwise. There is a small hole in the bottom of the plastic plug that allows coolant to drain without pulling the plug entirely out. I think this is because if you pull the plug entirely, it wants to shootout horizontally and make a mess. It's really up to you but I thought it drained faster if you pull the plug completely. The plug has a little o-ring on it when you remove it so don't lose that!! Once the plug is removed, open the radiator cap to let the air run through it. It takes quite a long time to drain so leave it draining for 10-15 minutes, even when it gets to a slow dribble.
2. As the radiator and coolant system is draining, remove the coolant overflow reservoir(right/drivers side of the rad in the engine bay). The black cap and hose pops out, remove it and rest it on the battery or something. The actual reservoir slides onto a little plastic track and sits in a plastic plug hole on the bottom. Removal will require unbolting the battery mount which covers to top of the battery. Grab the reservoir firmly with both hands, and pull directly straight up to remove it. It may take a little elbow grease but it comes out quite easy. Empty this coolant into a bucket or however you plan on disposing it. I took some wipes and cleaned off the outside, and I put the reservoir under my tap and ran water into it to clean out the buildup of some gunk in the bottom. Once clean and mostly dry, put back into the plastic hole and plastic track in the engine back, reattach the battery mount, and insert the hose and cap for the reservoir.
3. Once 10-15 minutes has passed and you feel confident that the coolant is drained. Insert the petcock til it stops turning and take distilled water and fill the rad through the radiator cap hole. I was able to get about 6.5-7L in. Once the rad is full, squeeze the main hose, that goes from the top of the radiator and into the engine, several times to get some bubbles out. Top up with the distilled water, reattach the radiator cap.
4. The radiator and engine is now full of mostly distilled water with some diluted old coolant. Ensure the petcock and rad cap are securely attached and closed. Turn your temperature in your truck to full heat. (Don't forget the rear heat control too). Now don't turn on your blowers, merely set the dials to full heat. This cycles the coolant through your heaters and therefore through the whole system. Turn the truck on and idle it for 15 minutes. I made sure my truck was up to temperature and let it run at that temperature for 5 minutes. This makes sure the water circulates the whole system and it gets hot enough. Turn off the truck when you are done.
5. This is your first full flush. Make sure to be very careful, the coolant/water is 90 degrees celsius at this point. Get back on the ground and slowly open the petcock with your hand positioned above to avoid the hot liquid. The steam coming out of it will probably get you and I actually managed to drop the petcock into my drain bucket because it was so hot! Again, let it drain out for 10-15 minutes. Don't be alarmed if it looks like your engine bay is smoking [emoji14] , it's the steam. Since the system is now pressurized, it's gonna PISS out of the drain hole really fast so watch out!
6. In order to truly flush the system, a couple drains are required so repeat steps 3 and 4. I went a little over kill and I did 3 full distilled water fills and drains. Even at the end, the fluid coming out was tinted green (imagine watered down gatorade).
7. Once you are satisfied with the colour of the liquid and the amount of time it's been taking [emoji14] , reinsert the petcock and make sure it is tight (stops spinning, don't overdo it). Many people/Toyota recommend a 50/50 mixture of distilled water and coolant. On the back of the coolant jugs from Toyota, they state the specs for different mixtures levels. I likened this to mean that a true 50/50 doesn't really matter as long as you have more coolant than distilled water (in colder climates). The coolant jugs from Toyota come in 3.7L jugs. The system takes 8L without a rear heater and it takes 9L with a rear heater. Now the rear heater lines won't drain because of gravity and this is why I did so many distilled water flushes and drains. The PO didn't use the right coolant so I wanted to make sure it was at least mostly distilled water in there. I added a full 3.7L jug into the rad, then I added a full jug of distilled water (4L), and I topped the rest off with coolant from the second jug I purchased until the rad was full.
8. The radiator and engine are now full of a somewhat accurate 45/55 coolant to distilled water mixture. Take the coolant from the second jug and fill the reservoir to about 1/3 of the way to the full line from the low line. Hard to explain but there should be room for 1.5-2" of empty space for liquid below the full line. Use distilled water to bring the level up to full. This is roughly a 50/50 mixture. Ensuring the heater lines in both the front and the back are turned to full heat, turn on the truck with the radiator cap OFF or REMOVED. This will allow bubbles to escape from the system. Leave the truck running for 10-15 minutes. During this time, squeeze the top rad hose gently every few seconds to "burp" the truck and push bubbles out. As the coolant is running through the system, bubbles will occasionally pop up. As the bubbles come up, the coolant levels drop obviously, so I used the coolant to top it up. It dropped more than I thought so I used some estimation skills between distilled water and coolant to figure out a 50/50. Once the coolant is getting warmer and bubbles aren't popping up anymore, you can reattach the radiator cap and turn off the truck.
Ta-da! You're done! Again, I am pretty amateur at this stuff so this is all I've learned from doing it myself. I found information online was spotty at best so this was everything I could think of to try to help more guys like me! If anyone has any tips or tricks they'd like to add, feel free!
Thanks for reading
So I decided to do my own writeup. This is my first writeup for anything so if anyone has any other tips that are helpful, feel free to add them!
A coolant flush is a drain/dilution of the coolant in the system and a replacement of that coolant. A traditional radiator flush only drains what's in the radiator and not whats in the engine (I think).
I wanted to do a full coolant flush because my bozo PO used green coolant instead of the Toyota Red which these trucks need.
The first step is to drain. I found that the rad and engine drain much better if the engine is hot. Now BE CAREFUL, the coolant coming out of the rad is 90 degrees Celsius. The good thing is that the drain is engineered in such a way that you can easily not get burned.
1. Get down on your side/back under the truck and from the "facing the truck" perspective, there is a little white plastic "petcock" or drain plug on the left or passenger side facing the rear. The plug unthreads counterclockwise. There is a small hole in the bottom of the plastic plug that allows coolant to drain without pulling the plug entirely out. I think this is because if you pull the plug entirely, it wants to shootout horizontally and make a mess. It's really up to you but I thought it drained faster if you pull the plug completely. The plug has a little o-ring on it when you remove it so don't lose that!! Once the plug is removed, open the radiator cap to let the air run through it. It takes quite a long time to drain so leave it draining for 10-15 minutes, even when it gets to a slow dribble.
2. As the radiator and coolant system is draining, remove the coolant overflow reservoir(right/drivers side of the rad in the engine bay). The black cap and hose pops out, remove it and rest it on the battery or something. The actual reservoir slides onto a little plastic track and sits in a plastic plug hole on the bottom. Removal will require unbolting the battery mount which covers to top of the battery. Grab the reservoir firmly with both hands, and pull directly straight up to remove it. It may take a little elbow grease but it comes out quite easy. Empty this coolant into a bucket or however you plan on disposing it. I took some wipes and cleaned off the outside, and I put the reservoir under my tap and ran water into it to clean out the buildup of some gunk in the bottom. Once clean and mostly dry, put back into the plastic hole and plastic track in the engine back, reattach the battery mount, and insert the hose and cap for the reservoir.
3. Once 10-15 minutes has passed and you feel confident that the coolant is drained. Insert the petcock til it stops turning and take distilled water and fill the rad through the radiator cap hole. I was able to get about 6.5-7L in. Once the rad is full, squeeze the main hose, that goes from the top of the radiator and into the engine, several times to get some bubbles out. Top up with the distilled water, reattach the radiator cap.
4. The radiator and engine is now full of mostly distilled water with some diluted old coolant. Ensure the petcock and rad cap are securely attached and closed. Turn your temperature in your truck to full heat. (Don't forget the rear heat control too). Now don't turn on your blowers, merely set the dials to full heat. This cycles the coolant through your heaters and therefore through the whole system. Turn the truck on and idle it for 15 minutes. I made sure my truck was up to temperature and let it run at that temperature for 5 minutes. This makes sure the water circulates the whole system and it gets hot enough. Turn off the truck when you are done.
5. This is your first full flush. Make sure to be very careful, the coolant/water is 90 degrees celsius at this point. Get back on the ground and slowly open the petcock with your hand positioned above to avoid the hot liquid. The steam coming out of it will probably get you and I actually managed to drop the petcock into my drain bucket because it was so hot! Again, let it drain out for 10-15 minutes. Don't be alarmed if it looks like your engine bay is smoking [emoji14] , it's the steam. Since the system is now pressurized, it's gonna PISS out of the drain hole really fast so watch out!
6. In order to truly flush the system, a couple drains are required so repeat steps 3 and 4. I went a little over kill and I did 3 full distilled water fills and drains. Even at the end, the fluid coming out was tinted green (imagine watered down gatorade).
7. Once you are satisfied with the colour of the liquid and the amount of time it's been taking [emoji14] , reinsert the petcock and make sure it is tight (stops spinning, don't overdo it). Many people/Toyota recommend a 50/50 mixture of distilled water and coolant. On the back of the coolant jugs from Toyota, they state the specs for different mixtures levels. I likened this to mean that a true 50/50 doesn't really matter as long as you have more coolant than distilled water (in colder climates). The coolant jugs from Toyota come in 3.7L jugs. The system takes 8L without a rear heater and it takes 9L with a rear heater. Now the rear heater lines won't drain because of gravity and this is why I did so many distilled water flushes and drains. The PO didn't use the right coolant so I wanted to make sure it was at least mostly distilled water in there. I added a full 3.7L jug into the rad, then I added a full jug of distilled water (4L), and I topped the rest off with coolant from the second jug I purchased until the rad was full.
8. The radiator and engine are now full of a somewhat accurate 45/55 coolant to distilled water mixture. Take the coolant from the second jug and fill the reservoir to about 1/3 of the way to the full line from the low line. Hard to explain but there should be room for 1.5-2" of empty space for liquid below the full line. Use distilled water to bring the level up to full. This is roughly a 50/50 mixture. Ensuring the heater lines in both the front and the back are turned to full heat, turn on the truck with the radiator cap OFF or REMOVED. This will allow bubbles to escape from the system. Leave the truck running for 10-15 minutes. During this time, squeeze the top rad hose gently every few seconds to "burp" the truck and push bubbles out. As the coolant is running through the system, bubbles will occasionally pop up. As the bubbles come up, the coolant levels drop obviously, so I used the coolant to top it up. It dropped more than I thought so I used some estimation skills between distilled water and coolant to figure out a 50/50. Once the coolant is getting warmer and bubbles aren't popping up anymore, you can reattach the radiator cap and turn off the truck.
Ta-da! You're done! Again, I am pretty amateur at this stuff so this is all I've learned from doing it myself. I found information online was spotty at best so this was everything I could think of to try to help more guys like me! If anyone has any tips or tricks they'd like to add, feel free!
Thanks for reading
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