I read the sticky about cooling issues etc.

We just got another Honda in the family. My son bought a 2002 Civic EX with the 1.7. It only has 84,000 miles on it and it is MINT. It is a 5 speed sedan.

After a couple days' driving the temp needle started creeping up high, then coming down etc. Then it creeped back up. Idling the car in the driveway the temp needle went higher than it should have without the fan coming on. However, revving the motor just a little caused the temp to come down AND the fan to come on. I replaced the thermostat, and we jacked the front end up and burped the cooling system and added some coolant. After that, the fan came on when it should have, and the temp never made it half way, even when driving.

On a 3 hour drive the next day, it was fine, but then just at the end of the drive it started getting hot again and the reservoir was almost to the top. (not overflowing and not bubbling in there)

I am aware that these motors have head gasket issues. However, the coolant is clean, the oil is clean, there is no sweet smelling exhaust, or white smoke. No bubbling in the overflow tank when revving the engine. The fan is operating as it needs to.

I have (almost) resigned myself to do the head gasket on it. (done many over the years). I will do the timing belt and water pump while I am in there if I get to that point. I will check the head out and deck it if I have to.

Some of the reasons for the head gasket blowing on these out there on the Internet are "Well because they overheat" well....duh. Any aluminum head 4 cylinder that overheats is going to blow a head gasket. Is the cooling system on this generation inherently flawed or is there a poorly engineered head/gasket materials issue going on? If I do the head gasket, what steps can I take to make it more robust? We are not going to "tune" this one, it is only going to be his commuter.

Can anyone think of any other reasons that might cause the symptoms we are seeing besides the head gasket? Again, clean oil, clean coolant, no white smoke, no bubbling in the overflow. I know he told me the overflow was high (just up to the fill hole) at the end of his trip but I had overfilled it a tad when burping/topping off the system the day before.

THanks in advance for any input!

 

An update, if for nothing else but posterity:

did one of those block tests that bubble air from the radiator through blue chemicals….if the color changes to yellow then there is combustion gases present, that showed no sign of a failing head gasket.

definitely a circulation issue so we’re going up to a water pump and timing belt and go from there.

 

dont forget the thermostat

they do stick at times

 

Yet another update. I would love some more input! This one is making me crazy.


I am going to recap short as I can:

If you fill it up with coolant, it will come up to temp fine, hold a good temp fine. You can drive it and its fine. After enough driving, like 200 miles, or let's say at the end of a long trip you hit some stop and go traffic. Then it will get hot and start pushing coolant out of the overflow bottle---as in the radiator cap releases enough to allow coolant into the bottle, which eventually overflows. This, of course, leads to a loss of fluid, so any other driving after it cools down requires topping it back off.
It seemed to be to be a flow problem. Highway speed, with lots of air coming in the grill its fine.
Even when its acting up in traffic after a good bit of driving, if you rev the engine the temp needle comes right down.

So far we have:

*Replaced the thermostat
*Replaced the Radiator Cap
*Replaced the Water Pump (and hey at least we got a timing belt on it-it was time )
*Tested the Fans. (both work when jumping the relays....they do come on now and then on their own as well)
*There is ZERO white smoke in exhaust, nor does it smell sweet.
*There is ZERO coffee-with-cream slime in the oil. It is CLEAN
*There is ZERO milky slime in the coolant. It is CLEAN
*The heater core seems to work....you get hot air the moment you turn on the heat. (Although when it is acting up and I guess its low on fluid, the heat will get hotter with higher RPMs.)
*We did a Head gasket/block leak test several times: This is where you have a blue liquid chemical in a test vial that seals to the radiator neck. When the engine is at temp, you are supposed to rev the engine while drawing the air from the radiator and it bubbles through the blue liquid. If there are any combustion gasses in that air, the liquid will turn yellow. That has come back negative all three times.
*Replaced the Radiator, NO change

It still looks to me to be a circulation issue. When filling it today after replacing the radiator, the engine was up to temp, but revving the engine, never has produced the appearance of coolant rushing by the top of the radiator when staring down into the neck.

I feel like this ISNT one of those cases where some unfortunate soul is trying everything they can do NOT to do a head gasket....I've do plenty of them before....I just have ZERO reason to believe its actually the head gasket causing these issues.

The car has 89,000 miles on it and is in excellent condition, its had an easy life so far.

Thanks in advance!



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I have an issue similiar, long drive the engine at idle will heat but short drives and such idling no overheating. I had a shop do a coolant flush they said the coolant was so bad that it didn't have really any cooling properties to it. idk I owned car since 112k had 130k on it so I had it done it really seemed to work for a while. Eventually though on a long trip and some spirited driving, on my way back and at a red light realized it was getting got again, but it's weird cuz the fans at that point are NOT on. Turn heater on and its cold and I got to get driving quick to get the temp down. when it isn't overheating the fans definitely turn on and you can hear them in the cabin, and it stays fine. I was also worried about heading gaskets but no coolant in oil, no oil coolant no smoke, nothing.

 

Jumping in here: Have you replaced the radiator hoses yet? I have had cars with similar symptoms turned out to have a soft radiator hose that, when things get cool and the condensing coolant pulls a slight vacuum, suck flat -- and block flow. As the system gets hot and pressure builds, the pressure opens the hose back up and restores flow. Hence, the temp goes up and down.

Sometimes it's not the radiator hose that collapses but rather the inner lining of the hose, making it look fine from the outside.

Some of us remember lower radiator hoses with "springs" inside. Those things were intended to prevent the hose from collapsing. Sometimes that spring corrodes away and disappears, resulting in the same collapsing hose problem. If such a spring is missing, you can make one out of some suitable springy wire.