Yesterday while at a stop light, my engine temperature gauge was up near the red mark. After letting things cool down I added it least a half gallon of coolant to the system and empty overflow bottle. Now while driving the engine temperature is running normal when hot about the 50 percent mark.

However today I got out of the car with the engine off and I could hear coolant flowing through the hose to the overflow bottle, and never noticed this before. I turned the engine key to on (not start) and the temperature gauge is reading fine.

I thought coolant would only flow to the reservoir if the engine was really hot and the system pressure was high?

Any thoughts on this, and is it normal and ok?

Thanks,

And let us never forget 13 years ago today 9/11.

 

Hope it isn't a head gasket. My old Neon would gurgle in the overflow tank. It was combustion gasses leaking into the coolant passageways between the head and the block. Check the oil dip stick. Does it look normal? Is it over the full mark? Any light brown stuff on the dip stick or oil cap? Hope this isn't the case. When did you last notice the coolant level?

 

There could be air trapped in the system - this will cause sounds in the cooling system when the car is shut off.

Need to find the cooling system leak - you added that much, there is a leak some where. Once that is found and fixed, be sure to bleed the air out of the system.

 

The exhaust looks good, no funny or sweet smell and the oil level/color looks ok also.

I'll continue to monitor, as I have had to add coolant periodically over the last few months with nothing leaking on the ground. I also notice my gas mileage is down a little, but the engine is running ok?

A compression check might not be a bad idea I guess?

 

Suggest a cold, pressure test of the cooling system. This will disclose any external leaks visually, and if an internal leak is present you will notice pressure drop.

If pressure drop w/ no external leak, time to confirm HG w/ cylinder pressure test and inspection of cylinders for coolant. A leak of heater core would not be directly observable, but would allow coolant into pax area and usually notice a distinct coolant smell and steamy humidity.

I removed spark plugs and turned engine over to get a geyser out of 1 cylinder on my 94EX when I confirmed head gasket. I also had good running engine (most of time), but startup miss at times and slow loss of coolant.

good luck

 

@Corvair; leaking headgasket pumps combustion exhaust into the cooling system only when the engine is running. Otherwise that's a good thing for jerrym to check out (rule out?).

Sometimes heat will soak around immediately after turning off the engine, which raises the coolant temperature a little bit before it begins cooling off. That can push coolant over to the reservoir, only to be sucked back in when it cools down. That commonly happens without enough noise to notice.

Cold cooling-system pressure test won't hurt. Cylinder compression test won't hurt. If there IS a leak somewhere you can keep looking to find it.

 

Thanks for the input and suggestions guy's, going to do a little more testing before making a firm decision on what to do with a 97 Accord with 200k on it.

Been taking some short trips with the car, engine temperature seems fine, oil level ok, no white smoke from exhaust. When I shut the engine off coolant is still flowing into the reservoir, though squeezing the upper radiator hose pressure does not seem super high.

Do you think it is ok to drive under these conditions as long as there is coolant in the reservoir before start and temperatures remain ok?

Thanks!!

 

As long as you accept that an overheat may occur, requiring you to immediately abandon your trip and seek a stopping point. A tow may be necessary to get home. No one can predict how likely or unlikely this scenario might be.

good luck

 

before you spend a lot of $$$ replace your rad cap, When they fail, coolant will bubble out of the overflow tank like that. it's $10 and it works. I replace the one in my 94 accord when it was 11 years old and the one in my CL-S when it was also 11 years old. the accord was bubbling over and the CL-S I could see seepage around the cap.


also when the car is cold do this to properly bleed the system


1. start car
2. turn heater on max
3. open rad cap
4. open nipple on t-stat housing
5. add coolant to rad
6. as your added coolant, watch the nipple on the t-stat and once air quits bubbling out, close the nipple
7. top of rad and close
8. add coolant to the overflow bottle to the max line.
9. turn car off
10. when car is cold, check level and add enough to bring level to the MIN line. repeat this step until you no longer have to add coolant to get the level to min line when cold.

 

Yeu,

Took your advice, and filled and vented cooling system. Also purchased a new 16 psi radiator cap from the auto parts store. Took the car for a 20 minute drive yesterday, and now there is no coolant flowing to the bottle when I shut the engine off. Also the system pressure seems much higher when squeezing the upper radiator hose. I am going to go for a longer drive today, but so far so good!

Thanks to everyone for their help, and have a great weekend all.