Hello - i have a 2003 honda civic that i have to add antifreeze to every week. Antifreeze seems to be sprayed all over the between the engine and the radiator. It seems like the radiator overflow tank is filling up with the antifreeze not being drawn back into the radiator.i had this checked out at the local repair shop and they replaced the radiator cap, a few clamps and pressure-tested the system (it held pressure just fine). Any ideas why this is happening? thanks for any help you can give me. shadester
'03 civic radiator overflow problem
- Thread starter shadester200
- Start date
Pressure tests don't always find the problem unfortunately. If its between the rad and block I would think that your rad is leaking and the fan is spraying it all over the engine. Check the part of the rad where the plastic tanks are clamped to the metal core part, it may have white/blue crusty dried coolant on it if its slowly leaking.
Also have you had the water pump replaced ever? If thats leaking it would be harder to notice since it sits behind the timing cover.
Also have you had the water pump replaced ever? If thats leaking it would be harder to notice since it sits behind the timing cover.
N/A
N/A WorkRacer
I have been having the same problem! I keep having low coolant in my radiator and an overflowing overflow tank. At first the hose coming off of the radiator neck going to the overflow tank came off on the radiator side. The hose did not look very worn so I put a zip tie on it and put some more coolant mixture in my radiator and thought I was fine. Then I noticed it was still trying to overheat in bumper to bumper traffic. I had to pull off the highway to put more coolant in it and I noticed the overflow tank was all the way full to the cap, which is very unusual, I have had my car for over four years now and never noticed the overflow container more than an inch or so above max while the car is at normal temp and running. I will do what siboy put down, but I am very skeptical on the assumption that it is a simple leak.
Check your radiator for leaks.
back to another shop
Thanks to all for the ideas and sugestions. The local repair shop couldn't find any leaks, ran a pressure test
and that came back ok. They said the antifreeze was just from an overfilling overflow. The engine doesn't overheat except when it runs out of antifreeze. I think i will take it to a more reputable repair place. I am starting to agree with you that the head gasket is leaking. I understand this is fairly common on these engines. it's really a shame - I love this car! shadester
Thanks to all for the ideas and sugestions. The local repair shop couldn't find any leaks, ran a pressure test
and that came back ok. They said the antifreeze was just from an overfilling overflow. The engine doesn't overheat except when it runs out of antifreeze. I think i will take it to a more reputable repair place. I am starting to agree with you that the head gasket is leaking. I understand this is fairly common on these engines. it's really a shame - I love this car! shadester
sr6000
still a D
no it is a pin hole between cylinder and coolant and when run hard it pressurizes the cooling system blowing it out into the overflow tank, what little makes it in the cylinder goes out the tail pipe.Also and this is just my opinion I think it is the type of antifreeze honda used eating the headgasket
bgmiller7
New Member
I am having the same problem (which I found only after my car has been overheating like crazy). The only thing I can find is a weird coupler-type part in the overflow line, about half way between the tank and radiator. Two hoses connected by this coupler. The coupler looks like it is very restrictive to the flow of the coolant. I'm not sure if this is stock, or if a previous owner put it in.
Thoughts?
Thoughts?
Try a block tester, these can be loaned from autozone. But the leak down pressure test is probly the best. It sounds like a HG leaking. Happened to me also. Look at the positive side of this thing. If it turns out to be a head gasket, it gives you a chance to freshen up the motor's critical issues. Water pump, timing belt, head gasket, v-tec screen, and valve job. Mine runs better than ever! But mind the cost, if you're having the work done. JDM motors are fairly cheap, also from what I understand, they're not too tough to swap. I probly would have spent about the same money to replace, but chose to repair instead. But it could be as simple as a thermostat or possibly the system has an air pocket, and needs to be bled. Either way, good luck!
J T
New Member
My 03 Civic EX is having same problem...Overflow tank keeps filling and not returning to radiator...It does take a long time for my bottom hose to heat up ....I am going to try a thermostat today...I already replaced the overflow tank due to a top crack from overflow filling up....The car does not overheat at all and runs great 157K/ 5 speed .I hope its not the head gasket.....Any suggestions the car in Not overheating and runs great
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I believe its your coolant boiling at about 230f. I believe the temperature gauges on these cars are faulty. I will paste something i wrote a while back here.
out of curiosity i read up a fair bit online about people having head gasket problems with their 01-05 Honda civics. i have one and the cooling system setup seemed odd to me and i wasn't sure why they had such cold thermostats. what i discovered is that almost everyone (not all, but almost) who has a head gasket go has it happen right around 110-140k with the most being at 120. that is right when the first scheduled coolant flush is and many people mention just that-that they just had their cooling system serviced by Honda or someone else. with these Honda's the heater core is the high point in the cooling system. if you drain the coolant the only reliable way to get all the air back out is to jack the front of the car up till the muffler almost hits the ground then bleed the air out. if you don't there is a good chance (not guaranteed) that you will trap air in the heater core, which will at some point move into the block or cause issues and cause a hot spot in the motor and cause the head gasket to go.
also where the thermostat housing meets the block there are passages where coolant, oil and exhaust all pass through into the thermostat housing very close together. there is possibility for leaks there.
also i have a mechanical water temperature gage on my civic in addition to the one on the dash. as the car warms up they match, but as soon as the thermostat opens at 170f the one on the dash stops! the mechanical one will continue to climb until it reaches 205f when the fans turn on but the one on the dash does not move! my previous civic (2005) had a rad fan that would sometimes quit. i had it twice where i was stopped at a stoplight and i could hear my coolant boiling. got out and opened the hood and my overflow cap had blown right off and boiling coolant was shooting all over my engine bay out of it and the temperature gage was still below half both times! it had perfect operation from cold to where it stops just below half but would never move higher. so i believe that people are overheating their motors without even knowing it.
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J T
New Member
J T
New Member
Wholly crap! I will replace the thermostat and replace coolant with the car either Jacked up or the wheels on a parking curb best I can do ....I have heard about the incline before...When I add coolant to the radiator it just doesnt seem to stop bubbling..It slows down but I see it intermittently bubble.
J T
New Member
when i open the cap when cold I add antifreeze rev the ilde a bit, ...Leave open and add til its full, it bubbles then coolant goes down the radiator ,,,,am I waisting $ replacing the thermostat? I don't overheat at all I keep an eye on the radiator level every couple of days.....Just seems a while before the lower hose heats up...Was thinking therm. not popping open....
If it didnt open your car would overheat, blow a head gasket and destroy stuff i you kept driving it. So test it. Jack the car up so the front is as high as possible with the thermostat side of the engine higher than the drivers side. Run it at 2-3000rpm with te cap off until the thermostat opens you will see coolant flowing fast through the rad once it opens and the coolant level will drop. If you fill it completely before the thermostat opens then some will gush and bubble out which is normal. Fill it completely up after the thermostat opens and you have it running for a minute open. Then put the rad cap on and keep revving it jacked in the air like that until you fans come on. Then you have checked both your thermostat and fans and know your system is bled. Then if you continue to have problems you can troubleshoot knowing those components are fine.
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