Stuntdriver4.0

I have a 1997 honda civic lx and it is overheating. The motor was replaced with one from a junkyard because the previous one overheated and spun a bearing. The car will run fine on cool days but when it is hot outside and I have the a/c on it will start to overheat with 15 to 20 minutes. I took it to a mechanic and he replaced the thermostat and it didn't work. The radiator fan wasn't spinning so the motor was replaced and now it works. It still heated up so I took it back. He noticed hardly any air was coming out of the muffler and said it was possibly due to the catalytic converter being bad and exhaust was being thrown back into the engine and overheating it. I replaced the whole exhaust system with new parts (cat converter, resonator and assembly, and new muffler). I thought for sure this was the end of it but today it overheated again. I dont think its the head gasket because the radiator coolant has no oil in it nor does the oil in the engine look milky. I also flushed the radiator and bleed it for air and even got a new radiator cap and radiator overflow reservoir for it. I was told it could be the water pump but it is not leaking. I'm at a stand still and don't no what to do. Please help if possible, would GREATLY appreciate any info you have on the matter. I'm tired of throwing parts at the car. P.S. Spark plugs and the whole distributor were replaced new and timing was set, don't know if that will help.

Matt_75

The old 21 gun salute.



Have you checked compression lately? It could still be a head gasket. JMHO. Sounds like you've thrown a lot of money at it.

Let ezone reply to you to get a more accurate assessment.

mikey1

"not leaking" does not mean a water pump is good and doing its job, i would remove the pump and make sure the propeller inside is turning properly

pjb3

While you are technically correct I have never run into a water pump where the pulley or impeller was slipping on the shaft. Every water pump failure I have seem has been the bearing or the seal. Since removing and checking the water pump is the same as replacing the timing belt it is one of the last things I would check.

mikey1

yes, but he seems like he is down to "one of the last things to check" that is why i recommended it, broken propeller fins inside a water pump of great age are not uncommon, and will result in poor coolant circulation

anibis

Was an OEM thermostat used? Honda's can be picky with aftermarket t-stats.

How does the radiator look? Any missing rows? Clogged/missing fins?

Both fans running when the A/C is on? They should cycle frequently in a healthy system (although not 100% sure in 6th gens, they may run all the time).

If you are not going through coolant/overflow getting full or puking coolant out I wouldn't suspect its a HG problem; however the oil/coolant mixing symptom doesn't usually appear in these cars. The most common symptoms are air getting in the system and burning coolant.

I also wouldn't think its a water pump issue. I've never seen/heard of a fin breaking off in these cars. If it did break it would still be stuck around the water pump (nowhere for it to go) and would most likely be grinding/breaking the other fins as the water pump turns. I would think you would be able to hear it if this happened.