I have a 93 Civic DX 1.5L. I recently had a cracked radiator. Replaced it, belts, water pump, thermostat, seals and the hoses that enter and exit the radiator. My problem now is when the engine heats up, after about 15 minutes on the freeway I'm at work and when I shut off the engine and pop the hood, the resivoir is full of coolant. Before I drive it again, I refill the radiator using the resivoir and the cycle continues. Any thoughts as to what might cause the problem?

 

the resevior is where the coolant is suppose to go. When your motor heats up, the coolant heats up and overflows JUST A LITTLE into that resevior, and then sucks what ever overflowed back into the system. Thats suppose to be normal.

Now if you're talking like fills up the ENTIRE resevior that could be hinting something else. Try bleeding out your cooling system. Start your car with the rad cap off, and let it warm up. Air should bubble out.

 

I'll try that. The problem is the fluid fills the entire resevior. Then when the engine is cool, the resevior is still full and when I take off the radiator cap, there isn't any coolant that can be seen. I'll try running it with the cap off and see what happens.


Modified by kjkhemraj at 4:33 PM 6/13/2007

 

just wondering, did you replace the rad. cap when you put the new radiator in?

 

If you can get the system to burp, then cool. But, it's much easier and you're more likely not to get sprayed with hot coolant if you just use the bleeder on the upper water neck.

 

That was the cheapest, I've tried 4 different brands. I just took the cap off, ran the engine for about 15 minutes and every time it bubbled and the coolant dropped, I added a little more. We'll see if that worked. I put the cap on while the engine was still hot thinking that it should suck fluid out of the reservoir if needed.

 

I'm headed out to my car around 4pm CST and I'll check the radiator and see if I followed your directions in burping the system correctly. I'll post a response by 5pm tonight.

 

So Far So Good. I'll drive some more tonight and check to see if it's fixed.

 

Burping the system didn't do the trick. After I got home from work today, The upper and lower hoses felt hot and looked like they were bulged slightly. I just checked the system since it had time to cool thoroughly and when I opened the radiator, not coolant to be seen. The reservoir was full of coolant. It had evacuated but not returned to the radiator. Any suggestions?

 

replace the radiator cap. if the cap is doing its job in mantaining system pressure your overflow tank volume wouldnt increase at all, ITS NOT SUPPOSED TO. the only time the overflow is used is when your engine coolant overheats as it overheats coolant expands, if it had nowhere to go it would burst, as it cools it should be drawn back into the radiator by pure negative pressure, if not your cap is bad or you have a leak allowing the pressure in your cooling system to bleed off.

 

I'm on my 4th cap in about 6 months. I think they are all good and the problem is somewhere else. I think it's a bad gasket. I tried to bleed the system again and it slowly bubbled for about 20 minutes. Somewhere gas is leaking into the system. I think that's why the fluid isn't returning. There isn't a vacuum to draw it back into the radiator. Hopefully nothing is cracked or warped. My uneducated guess is a head gasket. I won't be able to research it any more for a couple of days. If anyone has any advice, please let me know.

 

if there is any type of other fumes or gas or oil in the coolant....you already know what it is....HEADGASKET! so get the head check and fix it. gl

 

any decent shop has a vacuum device which can be used to locate any cooling system leaks.it goes on in place of the radiator cap and is pumped up like a bike tire pump.leaks are seen as air bubbles at the leak point and also the guage(pressure) will go down if there is a leak.even if it costs a few bucks itll be cheaper than frying your motor.most shops would probably diagnose for free hoping to get your buisness for the repair.

 

sounds like it is time to have the coolant checked for exhaust gasses if there are any in it its time for a new headgasket and have the head checked and machined if needed

 

even though your on your 4th cap dsent mean that it's sealing right, try a new one again and if that dosent work and u have warrenty on that new tell them the it's fucked where the cap seals. anf if thats not the problem u probily have a cracked head or the head gasket is shot. how badly did u over heat it when the rad cracked?? i had a buddy who replaced his rad and the problem was just the cap so stop buying the cheap **** and spend the extra few bucks and buy one from honda

 

Sounds like a classic D-series headgasket to me . No air in the coolant, overflow filling up, coolant disappearing. Seems logical.

 

I have bought an OEM cap and it didn't solve the problem.
I'm going to try the combustion leak test, it's next cheapest. Does this look like a good one to get?
http://www.thetoolwarehouse.ne....html
I will then look into pressure testing the system. Does this look like a good one to get?
http://www.thetoolwarehouse.ne....html

 

Well, get the car to operating temp, (with the cap off) so the Thermostat is open and coolant is flowing in the tank.

Then rev the engine a bit, and watch the coolant. If it fizzes like a beer* then its the head, or headgasket.

Simple, and free.

Good luck.


*not foamy, it wont form a 'head' tho.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kjkhemraj &raquo;</TD></TR><TR><TD CLASS="quote">I have bought an OEM cap and it didn't solve the problem.
I'm going to try the combustion leak test, it's next cheapest. Does this look like a good one to get?
http://www.thetoolwarehouse.ne....html
I will then look into pressure testing the system. Does this look like a good one to get?
http://www.thetoolwarehouse.ne....html
</TD></TR></TABLE>
the first looks like an okay way to test but like already stated the cheapest way is to watch for fizzing of the coolant if you dont see any then you should test it with a tester like that on or take it to someone and have it tested. the Second one is a good pressure tester just make sure that you get the adaptors for the honda rad and rad cap.

 

I'm going to have the head gasket replaced. What should I expect to be a reasonable cost?

 

$250 or so?

 

Thanks. I'm calling a few places after work to get it done.