Need some advice on coolant bleed using the lisle spill free funnel

ZPWR

Yo fellow Z owners. I just did a recent coolant flush and bled it with fresh new coolant using a spill free funnel kit - brand called lisle. And boy does it take ages! Like I took nearly 2hrs with a friend just revving the car, letting it idle, burping the upper rad hose - rinse and repeat like 50+ times.

My issue is I'm not quite sure if I have bled all the air out 100%. First I'll go over the current symptoms:

- Car's heater would only kick in at MAX temp with/without AC. Anything lower it's cold air. Before I would get hot air even with AC on on high temps.
- Little but minor rough idle. Hard to notice unless you sit real still. It was def alot smoother before I did this coolant job.
- A slight hissing noise in the AC vents at high temps (28 deg C)

What I noticed during the bleeding using this funnel kit, alot of my air bubbles escaped during idling right after revving abit. And for some reason it only worked with the AC off but with MAX temp. During this time we squeezed the upper rad hose a few times to help with the process. Also the front end was raised by jack stands.

Also when I revved the car for 10-15 seconds the coolant level on the funnel would rise and drop back down when I let it idle. Is this normal?

I got to the point where very tiny little bubbles escaped out of the funnel to barely any at all. But I felt this wasn't good enough and I have suspicions that there's still abit of air trapped in the system. Do you have to keep going until literally ZERO air bubbles escape the funnel? I feel like that would take all day.

Also I read that there isn't a bleeder port for the 370z and only the 350z has one. Is there another way to get all the air out?

I'm also considering just vacuum filling the whole system just to be safe. Don't want no cracked heads or white smoke problems in my fairly new Z. Some scary threads in here that I've already read. Gonna give me nightmares

I'm on the process of buying the whole kit plus a compressor to make it all work.

Any thoughts and advice always appreciated. I always received great input from these forums. Thanks!

(sorry for the long post)

Spooler

There is a bleed port on to drivers side of the car at the top of the radiator. You can get to it from the inside. If you don't have heat then you have an air pocket more than likely. You have a 2012 that has the pressurized coolant tank. They are really easy to bleed. Not sure why you are having so much trouble.

ZPWR

Is that the bleeder screw that's hidden behind the airbox on the left side? I attached a pic of it. not sure if it can be seen well.

Also I'm not sure if my overflow tank is pressurised. I know there's another coolant system with 2 pressurised caps. But mine seems to only come with one. The other is just a black plastic cap. Attached pic also.

Any more helpful info would be appreciated. Thanks!

Attached Images

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Dreadnaught

You will have to remove your drivers side air filter housing to access the bleed plug. You will need a Phillips screwdriver to turn it.

Drain your coolant. Then remove your drivers side air box and remove the bleed plug. Close the petcock once the coolant is done draining then slowly fill the radiator. Have the bleed plug and your screwdriver ready to go so once coolant starts coming out of the bleed plug hole, you can put the bleed plug back in. Once you put the bleed plug in, continue to fill the radiator slowly.

Once the coolant is above the radiator fill neck, put the radiator cap back on. Fill your plastic coolant reservoir between the minimum and maximum lines. Then, start your car and let it get to operating temperature and feel your lower hose to ensure the T - stat has opened. Now, check and correct the fluid in the plastic reservoir once more then put the cap back on.

Finally road test your Z and monitor your coolant temperature.
Turn your heater on to help check if there is air in the system. Check your coolant in the plastic reservoir once more and correct as necessary.

Then

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SonicVQ

^^^ Excellent summary.
This is exactly what I did on my G37 last year, using the same funnel. It was quick an easy.

fryzia23

You never mentioned if the car overheats during idle. If it doesn't then I think you bled it properly. I would say just let it idle with the funnel attached until radiator fan kicks in. Put the cap on and drive it. If heater wouldn't kick at all then there would be an air pocket but if it kicks in on high then its ok. The heater works based on outside temp sensor so if its pretty hot outside plus heat soaked from being stationary, it won't blow hot until set to max. It almost sounds like you're over thinking it little bit. Over the years wrenching on cars I have been there myself. Some times finishing jobs like that your brain thinks that there might be something wrong because all of the sudden you pay close attention to detail.

ZPWR

This is great stuff. I'll save this for future coolant jobs. Thanks mate!

Yea sorry forgot to add that part. Oil and coolant temps were steady the whole bleeding process. No spikes. Radiator fan only kicked in with AC on at the start but once the car warmed up it turned on later with AC off. That's all with MAX heat settings. Interesting about the outside temp. Didn't know that's how heaters worked in our cars. Always thought it would blow hot hair dependant on your heat settings. And yes I do have a habit of overthinking things. Just scared about breaking something along the way or even after.



Any ideas on the rough idle part? I had smooth idle before I did the coolant job. Could air pockets cause rough idle?

Thanks again guys. This is helping alot.