97 accord SE, just replaced radiator cap and flushed and filled cooling system, my car can sit for 10 min and boil and steam from reservoir tank but the temp is normal. also my cooling fan don't turn on till i spin it by hand sometimes. When i drive it don't boil though

 

How about nicks & scratches in the radiator neck where the cap seals? That can cause it to leak even with a new cap.

 

Oh, yeah, do i need a new radiator or how could i fix that?

 

sounds like you need to burp the system more, defrost on full and press down and squeeze radiator hoses

 

There are a few simple items to try.

When the engine is cold, remove the radiator cap and make sure the radiator is filled to the top with coolant.

Put the cap on, and start the engine. Turn on the a/c. Do both fans on the radiator turn on?

You can also stop by your auto parts store and rent a radiator pressure tester. The radiator should hold about 15 psi. There is a youtube video by ericthecarguy on how to do this. It might be on a video for overheating.

 

yes both fans turn on, ill try to get a pressure tester this weekend.

 

Look down in the radiator neck, there's a "ledge" that's down a few mm from the top. THAT is the part that seals pressure against the cap. That ledge should have just a little bit of a ridge around it, and that's where you need to check for scratches & gouges. Also check the very top rim of the radiator neck. If it leaks THERE, it can suck air back in as the engine cools down.

If that part is messed up, then you need a new radiator. I've never heard of anyone being successful just getting an upper tank or something like that.

Like 5.56mm says, check whether there's any air pockets in the system. But if the cap doesn't seal properly, it can draw air back in every time the engine heats up & cools down.