My 2003 350Z is overheating lately. The coolant gets pushed into the reservoir tank and will not refill the radiator. As you can see in the photos, the hose is getting sucked, so there is a vacuum there.

Does anyone have any idea how I can fix this issue? All the mechanics I have been talking to all say to me they need to research the problem themselves and get back to me and never do.

So the antifreeze boils and gets pushed into the reservoir but not recycle back into the radiator. Any thoughts are appreciated.

 

Start by replacing your radiator cap. How many miles/kilometers does the car have on it?

 

I have changed the radiator cap and it still does the same thing.
There is over 200,000kms on the motor.

 

Also, make sure that the overflow tube is not blocked and coolant is able to flow BOTH ways. But, if you replaced the cap with one with the same psi. rating and the overflow tube is in good shape and it's still creating vacuum, I'd start thinking clogged radiator. Time for a flush or a replacement.

 

...btw, those ''mechanics'' you've been talking to sound like idiots.

 

If the overflow line is clear and the cap is working then replace the hose.
I don't know of anything else that would cause this

 

Then why didn't you mention that in the first place?

 

Ditto.

 

 

Ok guys, thank you all for your help.
I did go and buy another radiator cap as the cap that I bought last year I thought wouldnt be a problem but as you can see by the picture it was jammed.

Another issue was the heater valve had blown so I put a new cap on it also.
Then I burped the system using the old water bottle upside down trick on the radiator to remove the air and it seemed to have fixed the issues for now fingers crossed it stays under half way on the temperature gauge. So far so good

 

Wow, just wow.
Don't say you replaced the cap then admit you didn't. GTFO. Your issue would have been resolved after the FIRST RESPONSE TO THIS THREAD