Newton06

My Z06 is back after a 2018 T6 hit at VIR.

Today at VIR, the car began stumbling and surging under full throttle. Water temp skyrocketed to 271 degrees and max boost was between 0 & +1 PSI during WOT & surging.

On track shop that did the repair said the IC tank was almost empty.

They filled it and bled it, and it ran well for about 3 laps then the same symptoms returned.

No DIC or CEL codes.

They think there are bubbles in the system and are going to bleed it again.

The used a funnel filled with coolant and kept opening the two bleeder screws on the flat tube.

I've read that once air gets into this system, it is almost impossible to get it out.

Am I screwed?

atljar

Screwed? No. Going to get all the air out with the bleeder screws? No chance.

lordofwar

dealer,still under warrantey

BrunoTheMellow

Dealer or tilt the car up 45° + too get the air out.

Newton06

So the dealers are the only ones that can remedy this? Does this sound like the issue?

I'm sure they are going to say it's not covered under warranty because it was in a collision and repaired elsewhere.

Thanks.

BrunoTheMellow

Google "how to bleed c7 Z06 intercooler"

LagunaSecaZ06

It is possible to get an acceptable bleed by putting the front wheels on ramps or jacking them up as high as possible AND vacuum bleeding with the typical radiator bleeding tool. The dealer may have the GM vacuum bleed tool, which could get a better bled intercooler system. Either way you go, the system needs to be emptied, car tilted and vacuum bled. Using the tube method is only for topping off a mostly well bled system.

Bill Dearborn

Tried to return your call this morning. Call me when you get a chance.
****** Your inbox is full so I couldn't leave a number. If you see this before you leave the track talk to Doc, he has my number.

Bill

Newton06

Quantum bled it a few more time using the bleeder screws an said no more air bubbles came out.

Seemed like it fixed the problem, no more surging and what seemed like full power.

Should I still have a dealer bleed it?

Also, wonder if that system would benefit from something like water wetter.

Bill, I'll call you today.

I did set my PB after being out of the car for 22 months playing wilth another instructor in a 2019 Z06. I got a 2:03.0. His PB during our playtime was a 1:59.9.

There were only 2 or maybe 3 other cars on track with us, which is why I love these late second day open track sessions.

BrunoTheMellow

You're not listening to us. Get a flash light, look down right infront of your air filter box. There should.be a pink container.. how far down is the fluid ? You want at most 1/2" down (or basically the beginning of the curved top)

SladeX

There's quite a few threads on how to bleed the intercooler. The parts to do it yourself are inexpensive and timewise probably takes longer to get car tilted up than to hook up the bleeder setup and start pulling vacuum.

Bill Dearborn

One of the things I noticed when bleeding mine with the new S/C (tilted bricks) is even with the front tires resting on race ramps the bricks still tilted downward with the rear higher than the front. Then I jacked the car higher and used jack stands to lift the front wheels off the race ramps. Even with the jack stands almost at their highest setting the bricks were still nose down when I put a level on them. The higher I got the car the more air I was able to get out.

Here is what the SC looks like when it is disassembled:
2015/2016 SC with low bricks. Notice rear of bricks is below the top edge of the SC.


2017 and newer SC view. Notice rear of bricks is higher than top of SC base.



This is what the front of the SC looks like when the snout is removed.

The top holes on each side of where the snout mounts are the exit points for coolant flow through the bricks. The lower holes are the inlets. Notice even the exit holes are at least an inch maybe an inch and a half below the top of the bricks which are under the cover but we do know they are higher than the surface the cover is mounted on.


This is the snout showing how it plugs into the base of the SC and connects to the bricks. The holes on top of the snout which can barely be seen are where the manifold attaches. Rear holes are for coolant exit and forward holes are for coolant entrance to the bricks and they connect directly to the holes you see on the side.

Another view before snout was removed:


Finally, a shot showing the manifold attached to the snout:



So the highest exit hole from the bricks is below the top of the bricks so air can be captured at the rear of the bricks. Since the spacing is close and the tubes thin it doesn't take a lot of air to disrupt charge air cooling to the rear two cylinders. That is why it takes so much effort to get the air out of the bricks. The pump doesn't have sufficient flow pressure and flow capacity to force the air out. Same goes for the reservoir down by the right front wheel. The only way to get the air out is lots of vacuum filling steps where a little bit of air is pulled out each time and then replaced with a little bit of coolant as the vacuum filling tool releases coolant back into the system. Pull 25 psi vacuum and hold for 5 minutes. cut vacuum by shutting off valve to tool and then let system suck in coolant from the tool's reservoir.

Bill

Newton06

Thanks for the detailed post Bill.

I have an appointment at the GM dealership on Wednesday for a bleed.

I hope they have the proper tools.

I sent them the TSB you provided.