Hello all. 98 civic ex 200k miles. Due to hose failures car has overheated twice over last 3 years though I caught them both early. Waiting in a drive through I noticed temp warming up and exhaust smell from underhood. Once home found reservoir with black coolant and sooty residue but no coolant in the oil. Did poor man head gasket replacement by disconnecting all hoses and wires from head. Lift head off block. Gave it the eyeball with straight edge, looked good replaced gasket and put it all back together with correct torques. Started right up and runs great. Coolant now disapearing and have to replace about 4 oz every two days. Did block test with blue liquid. With motor on I could not get much air to flow through blue liquid tool. I took the coolant reservoir tube out and was then able to get air to flow through blue fluid tool. Liquid stayed blue. tested liquid back at muffler exhause and liquid turned yellow. I've read maybe it's the radiator cap but the cap I have is only 2 years old and wouldn't I see leaked coolant on radiator top or get the familiar sweet coolant smell when stopped or driving? No cooland drips. Any help or ideas are welcome. Thank you.

 

Most likely you warped the head during one of those overheats so now you have a coolant jacket leaking into one of the cylinders somewhere. With a borescope tool could be very obvious looking through spark plug holes which cylinder is steam cleaned.

 

Thanks for the reply. I'm thinking that if I get the car up to operating temp which opens the thermostat turn off the car then I could quickly force air into the coolant system which would then maybe push coolant into whichever cylinder might have the leak. Your thoughts?

 

Why bother? Get a cheap borescope, they're like $20-30. Poke it into the spark plug hole. Trust me, it's very obvious, the piston that is cleaner on top is the one that has a water leak if there is one. My money is on a warped head, which ain't too big a deal for you since you already did a head gasket... just another gasket and a trip to a machine shop. Grinding the head flat is around $100 last i had to do that.

 

That actually sounds like a good idea. Just watched a vid of head removal and replacement. One question on that process. If I take the head completely off to take to a shop, do I have to remove the valves and related hardware or can the head be worked on by the shop with all that still in there?

 

Depends on the shop. Call them and they'll tell you. Do make sure they GRIND the head and not MILL. There is a difference.

 

Sounds like you've replaced a lot of parts. Did you happen to replace the rubber hose going to the overflow bottle? I chased the same problem for over 2 months. My son's car would need antifreeze about every 3 days. The coolant was going into the overflow but would not go back into the radiator as it cooled. Thought it was a headgasket problem. Turned out that the hose was just old and cracked. When the hot coolant left the radiator, it puked into the overflow tank like it's supposed to. But when the engine cooled and the antifreeze was supposed to be sucked back into the radiator by the vacuum that was caused by cooling, the radiator would suck air through the tiny holes and cracks in the hose. Consequently, the radiator would lose AF and the engine would then heat up, but the coolant was unable to go back into the radiator. Replace that $2.00 hose that's been in there for over 200k miles and see if your problem disappears. Good luck.
Duane

 

Thanks for the input though you were still a big help. After a better look at the hose as you suggested I saw that it was good but at the same time I looked down under the radiator and bingo! Turns out, The radiator plug washer had slightly blown out. I could see it protruding on one side. I think what was happening is that as the pressure built up when being driven it would push coolant out but it would not drip onto any of the plastic, instead straight to the roadway. Once car was turned off, pressure would lessen there by stopping the leak. Once I replaced the plug washer all is good for a month now, no more lost coolant. Again, thank you and others that chimed in, greatly appreciated.