pgawanab69

I bought this car at an auction, so i know nothing about its maintenance history. I drive about 80 miles each way to work, which takes about 90 minutes. After about a week of driving it to work, one morning - about 60 miles in to my commute, the temp guage started heading towards the red. I turned the heat on (blowing warm air) and pulled over. Opened the hood, wasn't steaming and didn't hear any coolant boiling. I sat about 5 minutes, started the car and it went back to normal. It happened again on the way home, I got about the same distance and same thing. Stopping for 5 minutes seemed to cool it down enough and the temp returned to normal. I noticed both hoses coming off the radiator were hot and the radiator fan was working during both these episodes. That evening I replaced the thermostat. Coolant level was normal at that time.

I drove to work the next day and didn't overheat, but the air coming out the defrost was cool, as it was about 40 degrees outside. The car overheated again on the way home that evening. I took it to a shop and of course everything checked out fine - radiator hose temps were about 200 degrees taken with a IR thermometer. The defrost was blowing about 110 degree air. Had the same problems the next morning when it was about 40 out again. I took it back to him that evening and of course it was working fine again - this time the air coming out the defrost was only about 100 degrees but the hoses stayed around 200 degrees.

I thought maybe I have a bad headgasket - I've taken the rad cap off to check for bubbles, but it doesn't bubble any. From what I've read, this would suggest my headgasket is good.?. At this point I'm thinking I should try another thermostat, maybe I got a bad one. I can say that my coolant level has remained full this entire time. Also, when I changed the thermostat, I drained the radiator and when I refilled I bled the system per the Haynes manual. I had a steady stream coming out the bleed valve, no bubbles. To rehash - the heat never gets hot and after about 45-60 minutes of driving, the temp goes from normal to hot rather quickly. I appreciate any input you guys can give me. I apologize for the long post, just wanted to be thorough.

motegicivic

2 things come to mind, a bad radiator or a bad water pump, esp since it is happening when driving. Check the radiator, it is wet on the top seal?

Water pump most times you will see it drip, but if it old and aftermarket the blades can deteriorate and not spin.

Go_Race_Your_Self

Well since you know the fan is working, you can cross that one out. It could be a bad water pump like stated above. Check for any leaks under the car when you go out to start it next time.

Kev

pgawanab69

I have been looking for leaks/drips - haven't seen any. I'll go check again here in a bit. I appreciate the feedback. As for waterpump - would it run for an hour at high speeds if it weren't working properly and then suddenly start to overheat? I'm not sure when it was replaced, if ever - need to probably do it and the timing belt soon anyway. I was going to try to push it another 10K due to lack of fundage...

Go_Race_Your_Self

Well here is the thing. When your running at high speeds, the cool air is going through your radiator. So you're basically cooling the motor that way. Now if the pump isnt working, then over time it will start to heat up. You see what Im getting at here?

Kev

pgawanab69

Yeah, makes sense. What about the heat throwing cool air the whole time, same thing?

1bad-eg

Not seeing bubbles in the coolant with the cap off doesnt mean you dont have a bad headgasket. Headgasket can still be blown...how's the reservoir looking when the car overheats? And be carefull...driving it to and from with the overheating issue can do more damage.

pgawanab69

The res gets some coolant in it but doesn't fill up. I'm really hoping against the headgasket. I only keep driving it because when I drove it home yesterday it was fine (except for the heat not working) but then this morning it did it again. I'm going to try replacing the thermostat again and then if that fails maybe flush the system and perhaps replace the radiator. I just don't have the money to throw at this right now. Would prefer to fix the one thing that's bad instead of troubleshooting by replacing everything. I know that sometimes that's all you can do but trying to save some money if possible.

angrysmileyface

If you're doing the pump, might as well do a timing belt job since you would be in that area anyhow. Preventive maintanence cab be key to an engine leading a longer healthy life.

1bad-eg

Yea i understand completely...well keep us posted on what you find.

axpAJ345

my engine is doing the same thing but it only happens at long distances. i drove to dc from pittsburgh and when i slowed down, boom started to over heat. res was completely filled. makes me think thermostat since in winter it wasnted blowing warm air or warming up to normal temps ever, except when stopped for very long periods of time.

does anybody have any links to a walk through for the Thermostat replacement? i know this is a stupid little job but havent done one yet. would prefer to see one done before i pull things off my only vehicle that i use for work. ive used the walk thoughs on here before to fix a idle rev problem and it worked perfect. kinda spoiled since then. anyway. a link or post name with a thermostat replacement would be awesome. please let me know.

motegicivic

This was in the sticky section:

http://www.hondacivicforum.com/forum...acement-81130/

furious94ls

Make sure you didn't put the thermostat in backwards. Also, I'd do the waterpump/timing belt anyway.

axpAJ345

thanks for the link to the thermostat walk through. exactly what i needed. i'm gonna do this tomorrow. ill let everyone know if this takes care of the problem.