hondah

Hi everyone, I've been a lurker on the forums and have found a lot of great information.

I am in kind of a stump here, trying to figure out what is going on with the car. Some background info:

1996 Honda Civic D16y7 with only intake and exhaust

Symptoms:
Coolant boiling/smoking from radiator cap
Normal temperature reading on gauge
Very light white smoke/steam from exhaust (not enough to confirm HG)
Rusty water squirting out from exhaust
Fan is not turning on (jumped the wire and fan is actually working itself)(update 5/1 - fan is working)
Upper rad hose gets very hot, but lower one remains cold (update 5/1 - lower hose is hot)

Any help would be appreciated. I will try to provide more information if needed.

Thank you!

mk378

Engine cold, take radiator cap off, radiator should be full. Then start the engine (cold) with cap off and rev it. If you have steady bubbling or coolant surges out, there is a leak in the engine (most likely head gasket). A good engine will have little or no fluid motion in the radiator when cold.

If the "smoke" coming out the tailpipe smells like antifreeze, that is also a rather conclusive sign the head gasket is leaking.

hondah

Just tried what you said to do and there is no bubbles or surging. Should I do a compression test?

mk378

Compression test doesn't usually pick up a head gasket leak unless it's really bad, bad enough that other symptoms are obvious.

So you're actually not losing any coolant, or experiencing overheating?

hondah

Correct, no coolant loss or overheating. Any ideas on what that stuff is coming out of the exhaust?

Also, I just performed an oil change and the old oil was black and normal, no coolant in it.

Checked the spark plugs too and they don't have any trace of coolant, only smells like gas.

DumpdEJ6

If the top coolant hose gets hot but the lower one stays cold, you for sure have a bad thermostat. I suppose it could also be a plugged radiator.

I have no idea why rust-water is coming out of your exhaust. That is odd. Try replacing the thermostat first and see if you get coolant flow by warming the car up ad checking the upper and lower hoses again for heat.

SarahVTEC

Go rent a block tester at your local auto parts store. You only have to buy the test fluid.

hondah

Just checked thermostat and its working fine. I will be getting that block tester tomorrow.

Lilbee623

My Pontiac did the same **** and it turned out to be the water pump along with bad heads

hoopty hopper

youve got multiple issues going on
DumpedEJ6 is right your thermostat mightve opened when you tested it(more than likely boiled it) but did it function at the temp rating specified on it
if coolant is boiling from radiator cap pressure test the cap and radiator
flush the radiator check your overflow tank make sure its functioning properly
what are you using for coolant just water doesnt cut it
the rusty water out the exhaust looks like condensation turning cheap exhaust parts rusty
early stage signs for your headgasket going out white smoke from the exhaust, radiator coolant smells like your exhaust(should be able to smell it on the cap)
if your temp reading is at normal and you have all these issues check your temp sensor the radiator cap should not be blowing out if the temp is normal

hondah

Ok, just performed a block test and it came out good. Color remained blue, did not change to green or yellow. Also performed a compression test, which came out to 150psi across all cylinders. Lastly, my rad fan finally turned on multiple times, the lower radiator hose felt hot, however, there is still smoke coming from the radiator cap, which leads me to believe that it might be the cap.

JDMswagSerf

Rust in exhaust looks like its just condensation.
do you only get smoke when you first start the car up?

hoopty hopper

i do on mine but i have a cat delete on my car when i had the cat converter i didnt, my buddy has a bad cat converter and he blows a small amount until reaching operating temps if you get behind a truck that is driving around before reaching operating temp it has quite a bit of condensation coming out youll see it more often in the morning.Heres some info on it from NATEF.

Water is a natural by-product of complete combustion and is not harmful to the environment or our air quality. Water is formed by the engine when two hydrogen molecules from the fuel are drawn into the combustion chamber and are combined with one oxygen molecule FIGURE 51-2. Water is emitted as a result of complete combustion of hydrogen and oxygen. We could say that water is a by-product of completely burned hydrogen fuel. In fact, burning 1 gallon of gasoline in an engine creates about 1 gallon of water. Thus, water is formed in all internal combustion engines and is discharged along with all normal combustion gases through the exhaust system.

hondah

No, the smoke is continuous and now I do notice a sweet smell to it, like coolant burning.

JarvisW

You can try a leakdown test, but it sounds like you have a small leak in it.

Do timing belt, tensioner and water pump while you're at it.

Shouldn't take very long. A good long weekend. Take pics and bag n tag!