All those things are possible yes, definitely time for another pressure test.

 

I suppose with the extra heat some minor cracks might only be noticed when the car is at operating temp. It's kind of a pain to inspect the water pump. You need to jack it out with some bolts and take some slack off the timing chain. If you've never done it before you can skip the timing on accident. I replaced my water pump due to some bad bearings. I also ended up doing the timing chain, since I'm pretty sure it skipped a few teeth when I tried adjusting it.

It usually takes me about 2 hours to bleed air out of the system. I did buy an airlift recently, but haven't had a chance to use it yet.

I squeeze the hoses, turn heat, and fans on. Rev the engine a few times and then stop/start several times. The coolant will overflow the funnel when you rev it to 2-3K RPM since if you think about it...the pump is going off the chain. Even when I leave the cap off at idle the coolant will rise up, so I wouldn't worry about that too much. I get the final air out of the system after both hoses are hot and take it out for a drive. By the time I get home it's blowing real hot air in the cabin. I've done it this way at least 4-5 times without any issues.

My car starting overheating recently in the hot weather and I'm pretty sure it's my fans (they run slow). Have you checked your fans also to make sure they are working correctly?

 

Another update:

Drove the car about 10 minutes yesterday with no issues. Heat stayed hot at idle and my coolant reservoir wasn't raising much.

Checked coolant levels this morning and reservoir was just above max where I remember it being when cold. Pulled off the radiator cap and it was topped off as well. I then took the car for a spirited 20 minute drive and after about 15 minutes I lost heat at idle. When I got home I checked the reservoir and it was about 3/4 full. No overheating but I'm afraid it would have if I drove much further. Am I getting air introduced to the system through head gasket/cracked or warped head or am I still fighting bubbles?!

 

I woke up this morning and checked the reservoir after the car cooled overnight and it was still at 3/4 full. If it was simply coolant expanding then it should be pulled back in right? Am I having air displace coolant and then staying in the system therefore not allowing it to flow back in?

 

Attempting to bleed again and it's back to the same it was before. Overflowing the funnel when at 3k RPMs and cold lower radiator hose. I don't think there's any way this stuff could be happening again without air being reintroduced. I hate to do this but I'll be taking it to a shop next week to confirm my suspicions.

 

It sure sounds like bad news, at least it's easy to reproduce so a shop should have no issues with that part.

 

Well after countless tries with bleeding I'm still getting bubbles when I hold at 3k RPMs for 20 sec. nothing at idle. Although my car shows virtually no other signs of a blown head gasket I've concluded this is the only possibility. Really sucks to unknowingly purchase a car with such a major mechanical issue. I would have no problem had I known up front because I would have paid accordingly...

 

Definitely a very small breach in the headgasket becoming noticeable at higher rpm/load. I'll be pulling the heads tomorrow. Is there any reason to be concerned with rebuilding the bottom end while I'm at it? If so I may pull the whole engine.

 

I just wanted to follow up and let all future readers know that my car did in fact have a blown head gasket or warped head. I didn't see any signs of the head gasket being blown, but after replacing all is good. Machinist said he took off .004" on one head and .007" on the other. Engine runs great even though the FSM says you can only take off .004".

So in conclusion I definitely had a blown head gasket that only presented symptoms at higher RPMs. Only symptom was that the overflow reservoir smelled like gas and continually overflowed after driving 30+ minutes followed by overheating. My car even passed the block tester, showed decent compression, and had no signs of burning coolant out the exhaust.

 

Glad you got that all squared away!