0351jt

Hi Everybody,First time poster, let me just say how much I appreciate all the information on this website it’s a big help to guys like me trying to keep their cars on the road, mine is a 2001 Civic EX D17A2.
I’ll post my question and then a further explanation, basically my car was losing coolant and I’m sorting out why.

If you perform this test listed here…hose from overflow to bucket of water
https://www.civicforums.com/forums/3...ml#post4537165 And bubbles/coolant comes out at first but both stop after enough running time and the bubbles stop completely even held at idle, 2k, or 3k, is it is possible to have a bad head gasket (exhaust to coolant leak) or was I just failing to completely bleed air out of the system?

I didn’t have the car jacked up but it was on a driveway in 90f ran about 30 minutes till radiator fans came on twice, then when the bubbles stopped, gave it gas and turned heater on/off, during this test.

I was thinking the bubbles should get worse after runtime/heating up coolant/gas.




….Don’t need to read but here is the longer context.

2 weeks ago I noticed my coolant was boiling out the overflow, the temperature gauge didn’t move at all. Upon inspection I found the radiator cap internals had failed, the spring and little gaskets were just sitting in the neck of the radiator. I replaced the cap and bled the system of air as best I could, jacked the car up ran for 30 giving it gas, fans came on more than twice put the cap back on and drove the car.

A week goes by about 500 miles in 100f (in phoenix) and I notice the temperature gauge start to move just towards the middle at a drive thru (idle), I immediately turn the heater on and it drops down to normal. I find the overflow filled up with coolant that doesn’t go back into the radiator even when the car cools down. I’m assuming at this point my head gasket is bad but I want to test to confirm.

I change the thermostat just to do it and perform the bleeding process as listed here *below, leaving the cap off overnight and topping off in the morning, I had to put in about ½ cup in the morning (again I’m sure bad head gasket). Then I performed the test this afternoon.https://www.civicforums.com/forums/3...ml#post4537185

I’m thinking now that I might have fixed whatever the problem was (radiator cap or thermostat) and I just did a poor job bleeding the system causing the initial bubbles during the test.

Here is a video of when I first started the test and the initial bubbles at idle, I had the hose in block tester fluid, it very slowly started to discolor in a pattern which is how I noticed small amounts of coolant were flowing out along with the air bubbles. I’m thinking the coolant and not the air were changing the tester color.
Here is a video of after the bubbling/coolant flow stopped, wife had the car at 3k for 1 min, with and without the heater on.

sdaidoji

iTrader: (1)

good question - only one member actually did it and made the video.

one suggestion is - since it bubbled, and you are actually losing coolant from the coolant reservoir, then it~s already highly suspicious that you have a breached gasket.
therefore, if you still wants further confirmation, step one more and do the other test video using shop air pressure 100-150PSI. That would definitely tell you it is breached.

if it did not bubble with the easier hose/bucket test, it would be less likely.

Note that losing coolant from reservoir is almost a dead giveaway, anyway.

Wankenstein

For a possible cheap confirmation you can try a "Block Test" on it. It's a (free) rental tool from parts stores and $10 for (blue ) test fluid. It can detect exhaust gases entering coolant system. However, a block test can't rule out every type (location) of a head gasket breach. A leak-down test is the most comprehensive way to confirm a head gasket leak as well as check for compression loss.

Are you 100% sure there's not an external leak? Did you do a coolant system pressure test?

Slumpertcivic

sdaidoji

iTrader: (1)

Erm...

That test failed too many to be reliable for the D17 engines....

Wankenstein

Yes. However, it is a definitive test if it's positive and the test fluid turns from blue to yellow or green. Otherwise, even if the test fluid doesn't change color then a head gasket breach still cannot be ruled out and that's where a leak-down is the gold standard....along with the symptom (not test) of coolant loss in radiator without an external leak.

IMO a block test is a cheap place to start as long as the user knows it's not 100% conclusive unless blue test fluid turns green or yellow.

0351jt

Thanks for the help all.

So I ended up getting the spill free funnel which worked out great, well not great but it did show me the problem.

After an hour of idle, along with taking the engine to 3k a few times, she still bubbles alot when the thermostat opened up. So as I look at things its time to pull the head. Not something that I've been looking forward too as I'm no mechanic. I replaced the engine in this car but that was just a bunch of bolts, not really technical. I'll be going over the forum for tips.

Thanks again.

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