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Looks like my 15 Z has a lot of air in the tank. I’ve read through dozens of threads with many options and just looking for verification that the process in the thread below is the best current way to bleed this.
to be honest I tried every thread there was to get my system bled. even have a high end schwaben coolant bleeder kit I used on my porsche to pull a -35 in/hg and still had air in the system. finally found a used cooler bleeder for 400$ and bought it. once I figured the procedure out 30 minutes and theres 2 quarter size bubbles in the oem expansion tank.
its the best option on the market to get the air out and know its done properly
Here we go again! LOL. Expansion tank won't do **** for bleeding. I don't care what anybody says. You still need to get the air out of the bricks. Find somebody with a cooler bleeder or buy one yourself from Jarad. Let me know if you have questions.
Yeah definitely bleeding it first. The expansion tank is only the next step if that doesn’t work. Sounds like it will though if done correctly with the cooler bleeder.
Yeah definitely bleeding it first. The expansion tank is only the next step if that doesn’t work. Sounds like it will though if done correctly with the cooler bleeder.
the expansion tank will ad more fluid capacity to allow more time before heat soak. wont do anything to help bleed the system. if you have the oem bleed port I can bleed it . you need a gallon of coolant and either a bottle of blantons or mcallen 12yr. takes about 30 minutes. if you dont have the port you can get a universal port from jared with the male nipple about 50$
The bricks inside the SC are tilted with the rear of the bricks being higher than the front. If you have a 2017+ SC the bricks are tilted even more with the rear of the bricks being at least an inch higher than the rear of the bricks in the 2015/16 SCs. Having an expansion tank does nothing to cool the air going to the two rear cylinders if the bricks have air in them. Per GM Engineering the two rear cylinders have higher combustion temps than the other 6 cylinders and their intake charge doesn't get cooled properly if there is air in the bricks. That causes misfires and loss of power (not limp home mode because 137 mph can't be called limp home). Get the air out and the car noticeably stops losing power in the high rpm range at wide open throttle. The top speed in 4th gear, which was dropping by 10 to 12 mph comes back and it becomes easier to hit 5th gear speeds in the 155 to 160 range before the braking zone for the next turn. It may not recover all of its power but the SOP feel says it does.
After the air problem is resolved an expansion tank that adds another gallon of coolant capacity to the intercooler may help keep the intake charge cooler for a few minutes but more than likely won't help past 5 minutes (2 to 3 laps) of WOT or near WOT run time. By that time the intercooler coolant will have reached its peak temperature. Maybe if the expansion tank wasn't located in the hot engine compartment it would last longer.
The magnason 2650 kit comes with a small tank that sits toward the brake master cylinder and appears to be the highest point in the system. There is no mention of bleeding the system under vacuum just fill and start and watch the level.
Also the gspeed tank still higher than the bricks at the rear of the tank and has a bleeder valve there. The system is filled at stick location. There is also no mention of vacuum bleeding just install there fill cup and filler up lol.
I have a cooler bleeder and love it but kinda wonder if all the vacuum bleeding isnt necessary if the right tank is installed.
The magnason 2650 kit comes with a small tank that sits toward the brake master cylinder and appears to be the highest point in the system. There is no mention of bleeding the system under vacuum just fill and start and watch the level.
Also the gspeed tank still higher than the bricks at the rear of the tank and has a bleeder valve there. The system is filled at stick location. There is also no mention of vacuum bleeding just install there fill cup and filler up lol.
I have a cooler bleeder and love it but kinda wonder if all the vacuum bleeding isnt necessary if the right tank is installed.
This crude diagram I drew demonstrates the physical issues of getting the air out of the intercooler.
Adding a column of coolant above the fill port does nothing to push the air out of the bricks. The 2015/16 bricks aren't tilted as much as I have shown in the diagram which more accurately reflects the 2017-2019 Superchargers. The column of coolant will reduce the size of the air bubble because it weighs more than air and will compress the air in the brick. The intercooler pump doesn't have sufficient flow capacity to drive the air down to the brick connections to the snout so it can flow up through the snout and the intercooler manifold to bubble out the fill port.
Using a vacuum bleeder does two things that help remove the air. First, it expands the size of the air bubble so it lowers to the point some of the air can exit through the snout and the fill port. Second, under a 25 or greater in.mg vacuum air dissolved in the coolant is released and forms thousands of little bubbles throughout the intercooler circuit. The pump has the ability to force these bubbles into the snout from the bricks, hoses, heat exchanger and the reservoir down by the right front wheel. Once this air is removed from the system the vacuum pump is stopped and a valve is thrown that connects the intercooler under vacuum with another reservoir that has coolant at atmospheric pressure. The coolant quickly fills the intercooler replacing and absorbing some of the air. If the vacuum is pulled and released several times the air bubble at the top of the brick becomes smaller and smaller as more coolant is pulled into the circuit. The intercooler only holds about a gallon of coolant but it can still take several hours to vacuum bleed it if you don't use the cooler bleeder.
The GM ZR1 supercharge bleeding tool is better than the regular cooling system tools at getting the air out. It has a plug that fits in the fill port and lets the coolant flow through the vacuum/coolant reservoir hanging above the fill port. There are two hoses that connect that reservoir with the fill port plug which has two connections on it. The bottom of the fill port plug sits inside the intercooler manifold and intercepts all coolant flowing from the pump causing it to flow through the vacuum/coolant reservoir and then returns the coolant to the manifold so it continues to flow through the intercooler. That makes it easier to watch the air flowing through the system and determine if you are getting most of it out of the circuit. The big problem I saw with the GM tool is the two reinforced clear PVC hoses that went from the reservoir to the plug collapsed under a heavy vacuum and greatly restricted coolant flow to the vacuum reservoir.
This shows the GM tool attached to my car back in the summer of 2018 when we finally resolved the intermittent power reduction that happened at wide open throttle at 5200 rpm and above in 4th gear that would knock 10 to 15 mph off top speed even on cool days. This issue is only common on cars that were tracked and I only realized how bad it was when I took the car to Watkins Glen where I had run a 97 C5 with 345 HP and a C5Z with 405 HP and found the power drop on the C7Z was to the point it was about 9 mph slower than the C5Z on the back straight and matched the top speed of the 97 C5. From that point in the summer of 2016 it took two years working with the dealership and GM Engineering to find out there was too much air in the intercooler resulting in improper cooling of the charge air going to cylinders 7 and 8 thus causing misfires in cylinder 8.
Notice the coolant in the vacuum/coolant reservoir is opaque. This is because the vacuum bleed system is pulling a vacuum and air dissolved in the coolant is being released. If you leave the vacuum on long enough the coolant will eventually turn translucent again after all of the released air bubbles are sucked out of the intercooler. The hose running off to the left goes to another vacuum/coolant reservoir sitting on the ground and the vacuum applied to it comes from a shop air-driven vacuum source. This is why the Cooler Bleeder does a better job, it uses a vacuum pump that can generate a greater vacuum, it automates the running of the coolant pump, the vacuum pump and the periodic refilling of the intercooler.
Bill
Some good info. So it seems the "Cooler Bleeder" is the way to go?
It seems so. I have heard nothing but great reviews of the product and I can tell you the vacuum bleeder that I have (OEMTools 24444 Airvac and Refill Kit) can't get as much air out of the system as the cooler bleeder even after I spend several hours pulling and releasing a vacuum multiple times to pull more air out and to put more coolant into the system.
I used a hand held vacuum pump just to test with the car jacked up from the front, from the side, on a hill, etc. and was able to add over a quart, but it still has a small amount of air in the tank. The car runs well now that daytime temps are lower.
Those who have used to Cooler Bleeder seem to not have any air leftover and no longer have issues even in the summer.
I used a hand held vacuum pump just to test with the car jacked up from the front, from the side, on a hill, etc. and was able to add over a quart, but it still has a small amount of air in the tank. The car runs well now that daytime temps are lower.
Those who have used to Cooler Bleeder seem to not have any air leftover and no longer have issues even in the summer.
With the cooler bleeder the best I was able to get was 2 small air bubbles the size of nickels at the top of the tank. I have bled around 12 cars with and without expansion tanks. The cooler bleeder works better than the GM tool. I have a friend that has a shop here in Florida and he uses the GM tool and I am still able to pull more air out with the cooler bleeder.
Looking at that tank you are at least a half a quart low.
Let's hope that's the extent of it. I had a couple of inches of air in my expansion tank, and when I took it apart to install the LG kit, the intercooler and the lines were dry. Empty.
Hopefully that's not the case here. I just like repeating it to motivate other owners to check theirs. Also, the cooler bleeder works great. It's worth the money.
With the cooler bleeder the best I was able to get was 2 small air bubbles the size of nickels at the top of the tank. I have bled around 12 cars with and without expansion tanks. The cooler bleeder works better than the GM tool. I have a friend that has a shop here in Florida and he uses the GM tool and I am still able to pull more air out with the cooler bleeder.
I suspect part of the problem with the GM tool is it takes longer to pull the air out and they give up too soon. When GM had the dealership use the new ZR1 tool on my car 5 plus years ago it took the dealer mechanic 2 hours to get the amount of air at the top of the reservoir down to what GM engineering said was too much but still an acceptable amount. He had to be there working the bleeding process (applying vacuum, running the pump at times, releasing the vacuum and repeating over and over) the whole time. With the cooler bleeder, you set it up and let it do its thing which means you can do something else while it is working.
I suspect part of the problem with the GM tool is it takes longer to pull the air out and they give up too soon. When GM had the dealership use the new ZR1 tool on my car 5 plus years ago it took the dealer mechanic 2 hours to get the amount of air at the top of the reservoir down to what GM engineering said was too much but still an acceptable amount. He had to be there working the bleeding process (applying vacuum, running the pump at times, releasing the vacuum and repeating over and over) the whole time. With the cooler bleeder, you set it up and let it do its thing which means you can do something else while it is working.
11-01-2023, 12:28 PM
Bleeding Supercharger Coolant
