My 91 hatch started over heating one day and it bogged a little bit. So I parked it and didn't drive it until I changed the head gasket, timing belt, timing belt tensioner, water pump, intake mani gasket, exhaust mani gasket, new coolant, bled the cooling system and tested my oem thermostat to make sure it worked. I was driving for about 15 minutes and the car started getting hot again. I have no idea what it could be. I don't think my fans turning on either. I have a little leak out of a hose but I'm replacing it and I haven't let it get low on coolant. Can anyone chime in and help? It's my daily and not driving is really getting to me. Been working on it and doing research for the past week with no luck. Thanks guys.

 

Forgot to mention my heat also isn't working.

 

Sounds like it could be air trapped in the system and also in the heater core. Also check the radiator for cracks that will start to seep when the system gets hot and pressurized.

 

I had this same issue with my first CRX and i when nuts trying to figure it out. For me, i ended up having air trapped in the system. I had to bleed it out, and it took quite a while.

 

Thanks for the help guys. So I bled the cooling system again, it seemed to be fine, was at normal operating temperature and the heat was working, took it for a little drive and the heat stopped working again and it was starting to get hot. Didn't let it over heat but I really don't know what this could be. One of my hoses has a little leak so I'm replacing it but that wouldn't be the cause of all this would it? From what I know the rad fan didn't turn on either.

 

Are you 100% sure that your thermostat is functioning properly? You said you tested it, but do you know that it's opening at the correct temperature? You can't just throw it in boiling water to test it. A bad thermostat will also cause a no-heat condition. Thermostats are cheap, I find it odd that you didn't replace this while you had the entire top end apart.

You should really ensure that the entire system is bled properly. You should also double check that the hot/cold valve on the heater core coolant line is properly connected and functioning, if this valve is broken or plugged it would help explain the no-heat issue. Another possibility of your no-heat is a clogged heater core, often times you can disconnect the hoses from the firewall and flush out the core with a garden hose.

I realize you replaced the head gasket already... Do you see any bubbles rising to the top of the rad when the engine is running? This is a sign of a blown head gasket. Does the coolant smell like exhaust? Any white smoke coming from the muffler? These are other signs.

You should really solve the rad fan issue as well, that isn't helping your situation at all.

 

Sounds like air
That small leak can bring air in
When you bleed it, have the heater **** set to hot

 

Bleed it for like 30 min, reving it can help get trapped air out.
If that doesn't work. I would look into the fuel system. The same problem still exists as before it sounds like. Bleed it really good I leave the radiator cap off and the bleeder valve open if there is one, rev it some until the bubbles completely stop.

I would test the fuel pressure and injectors if all else fails. And timing.