If your Honda Civic has a blown head gasket, it'll do one of two things: over-heat or not start. Now, if you have already verified that the cooling system is full of coolant, that the water pump is working, and that both the thermostat and radiator fan motor(s) are working too, then your Honda Civic probably has a blown head gasket. This article will show you how to verify this with four different tests.
Two of the Honda Civic blown head gasket tests don't require any tools to do and can be done under 5 minutes. The third blown head gasket test requires a compression tester and fourth a block tester. All four are very easy to do and will effectively let you know the condition of the head gasket on your Civic.
Contents of this tutorial:
- Symptoms Of A Blown Head Gasket.
- HEAD GASKET TEST 1: Engine Oil The Color Of ‘Coffee With Too Much Creamer’.
- HEAD GASKET TEST 2: Coolant Shooting Out From Open Radiator.
- HEAD GASKET TEST 3: Engine Compression Test.
- HEAD GASKET TEST 4: Using A Chemical Block Tester (Combustion Leak Tester).
- More 1.6L Honda Civic Tutorials.
You can find this tutorial in Spanish here: Cómo Probar El Empaque De La Cabeza (1.6L Honda Civic) (at: autotecnico-online.com).
Engine Overheating Diagnostics: The following tutorials will help you troubleshoot the source of an engine overheating problem:
- Common Causes Of Engine Overheating (1995-2000 1.6L Honda Civic).
- How To Test The Radiator Fan Motor (1995-2000 1.6L Honda Civic).
- Radiator Fan Motor Switch Diagnostic Tests (1995-2000 1.6L Honda Civic).
- How To Bench-Test The Radiator Fan Relay (1996-2000 1.6L Honda Civic).
- How To Test The Thermostat (1995-2000 1.6L Honda Civic).
Symptoms Of A Blown Head Gasket
The most common cause of a blown head gasket is engine overheating, which usually happens because of one of these issues:
- The radiator fan isn't working.
- There's no coolant in the system due to a leak somewhere.
- The thermostat is stuck closed and won't let coolant circulate.
When the head gasket gets blown on your Honda Civic, you'll notice one or more of the following symptoms:
- The engine is overheating, but you've already ruled out issues with the radiator fan or thermostat.
- White smoke is coming from the tailpipe, and it smells like antifreeze burning. This is a strong sign coolant is leaking into the combustion chambers.
- Your Civic's engine won't start, even though:
- You've confirmed it's not an ignition system issue because there's spark at all the spark plug wires.
- You've verified the fuel pump is delivering fuel to the injectors, so it's not a fuel issue.
- The engine oil looks thick and has a tan or off-white color. This can happen when coolant mixes with the oil, another sign of a blown head gasket.
HEAD GASKET TEST 1: Engine Oil The Color Of ‘Coffee With Too Much Creamer’
This first test is a simple test and checks for one of the most common results of a blown head gasket on a Honda Civic which is coolant mixing with the engine oil.
In most cases, this is probably the only test you may have to do, to verify a blown head gasket, and not have to do the other two tests. But if this test doesn't conclusively verify a blown head gasket, then by all means proceed to the other two head gasket tests.
OK, I'll stop talking and we'll get this show on the road, this is what you need to do:
- 1
Open your Honda's hood.
- 2
Pull out the engine oil dipstick.
- 3
Check the condition of the engine oil sticking to the dipstick.
- 4
You're gonna' see one of two things:
1.) The engine oil will be a creamy tan/off-white color.
2.) The engine oil will be its usual normal color.
Alright, let's interpret the color of the engine oil:
CASE 1: The color of the oil is a light tan, like coffee with too much creamer. This result confirms that your Honda Civic's head gasket is blown.
If you're wondering why the oil looks like this? Well this is what happened:
1.) Your Honda Civic overheated to the point that the cylinder head warped (since it's made out of aluminum). This led to the head gasket to burn.
2.) Once the head gasket burns and the head warps, the head gasket is unable to keep engine oil, coolant, and compression/exhaust gases from mixing.
3.) This leads to the coolant entering the engine oil pan. As both of these mix, the result is an engine oil that is an off-white/tan color.
CASE 2: The color of the engine oil is normal. So far so good, but more testing is necessary to make sure the head gasket is not blown (especially if your Honda Civic is overheating or not starting), go to: HEAD GASKET TEST 2: Coolant Shooting Out From Open Radiator.
Here's the reason why: In about 90% of the times, a blown head gasket will cause the engine's coolant to mix with the oil, but not always. And so another test or tests are needed to either confirm a blown head gasket or exonerate the head gasket as blown. The next test is to see if the engine's compression/combustion gases are escaping thru' the radiator.
