byzelo

I don't know a lot about cars, so please be patient with me.

My 1997 Civic started overheating a couple weeks ago. Never too hot, but the needle would jump 3/4 of the way up, and then back down to regular temperature (even while driving on the freeway). I had the thermostat replaced on Monday and it drove fine Tuesday, but Wednesday when I went to get in my car there was a huge puddle of what I'm assuming was coolant under my car (it was clear in color and i originally thought it was water but my boyfriend says coolant). My car never has leaked before then. My reservoir is full...

I drove it home and it seemed okay until I was down the street from my house and it started getting hot again.

I'm not really sure where to go from here?


Update: I just read one of the other threads (I'm new to the forum, so again please be patient lol), and one of the causes is the head going bad. One of the symptoms listed for that is your heater only blowing cold air, and mine does that. As far as the other two, I'm not positive. I had my heater core replaced a couple months ago. I hope you guys have other reasoning besides just the head... that sounds like a nightmare to replace.

ezone

If it's leaked a big puddle of coolant coolant on the ground, that's bad --STOP DRIVING IT!

Refill the cooling system (the radiator, not just the reservoir) and figure out where the leak source is.

MANY things can leak coolant other than a head gasket or head problem, but overheating can and will cause damage to-- or ruin the head gasket and/or head.

Wankenstein

Who replaced the thermostat?

As Ezone stated there are several potential sources for leaks because the coolant sytem is pressurized. A lot of people address an overheating issue by changing out the thermostat first since it's usually an inexpensive part. A failed thermostat is typically either stuck open: will take longer for the engine to reach operating temp OR stuck closed: overheats quickly since coolant cannot circulate. A thermostat can get partially stuck closed/open but that's not as common.

From the symptom you described: "the needle would jump 3/4 of the way up, and then back down to regular temperature (even while driving on the freeway)" it's possibly a failing water-pump and has now started to leak. Is the coolant puddle closer to the driver's side front tire or the passenger side front tire? Run (idle) the engine while in park, interior heater on max heat, blower fan on high and look under the car for coolant leaks and report back.

Some simple inexpensive things to try is:
1) check the radiator cap (youtube or google how-to)
2) inpsect. test (for blockage) and clean out the reservoir tank and overflow tubes.
3) bleed air out of coolant

If, it is the waterpump you'll want to have it replaced immediately or you will most likely end up with a head hasket issue from too much overheating if you keep driving it.

Please enjoy this educational and fun-filled video about overheating diagnosis by ETCG:

byzelo

UPDATE: We figured out the issue. The hose clamp on the hose connecting to the thermostat was stripped.... So all the coolant was leaking out of there.

I'm so thankful for a quick, easy, and extremely affordable fix.

Thank you for the replies!!

Wankenstein

Good to hear. You should watch the video for educational purposes as you never know when you might need that info. Also, inspect all the coolant and heater hoses (and especially the hose under the distributor) for wear and buldging as it's much cheaper to replace a hose than a head gasket (due to overheating).

ezone

This!
The distributor O ring on those engines is usually leaking by the time it hits 100k (and valve cover gasket) and that oil leak lands right on a heater hose and the oil will soak in and ruin the rubber hose....The rubber gets soft and swollen and can easily split open.