TEST 4: Using A Chemical Block Tester (Combustion Leak Tester)

Block Tester To Check For A Blown Head Gasket (1.6L Suzuki Sidekick -1.6L Geo Tracker)

If the 3 prior tests cannot confirm (or disconfirm) a blown head gasket on your 1.6L Sidekick (Tracker), then you need to perform a combustion leak test with a block tester.

This test is accurate and the only reason I don't include it at the beginning of the tutorial is that the first 3 tests correctly identify a blown head gasket 95% of the time (not to mention you don't have to buy a block tester). In that other hard to diagnose 5% of the cases a combustion leak test is THE test.

This is how it works:

  1. A blue liquid chemical, which is blue in color, is placed in the tester (see photo above).
  2. The tester assembly is then placed on the open radiator neck (you may have to drain some of the coolant in the radiator since this tool needs to ‘gulp’ some of the air inside the radiator).
  3. The rubber bellow is then squeezed to suck in the air up through the two fluid-filled chambers. As the air bubbles up through the fluid, it will cause a chemical reaction.
  4. If the blue chemical turns yellow (for gasoline engines), then combustion gases are entering the radiator thus confirming a head gasket, a cracked blocked, or cracked cylinder head issue.
  5. If the blue chemical doesn't change color, then you can conclude that you don't a head gasket, a cracked blocked, or cracked cylinder head issue.

You can shop for one here:

Frequently Asked Questions

1.)  How can I tell if the cylinder head is cracked?

The cylinder head has to be removed and visually inspected. If the crack is wide enough, you'll be able to easily see it.

Sometimes, a visual inspection proves inconclusive, this is why it's important to let a machine shop pressure test it for you.

2.)  Do I need to resurface the cylinder head?

YES, you need to resurface the cylinder head! You should never reinstall the cylinder head or cylinder heads without first having a Machine Shop resurface the cylinders heads (particularly over an overheating condition).

Now, of course, if you (or the machine) have checked it with a straight-edge and there's no warpage, then and only then is the cylinder head not resurfaced.

More 1.6L Suzuki Tutorials

You can find a complete list of tutorials in this index: Suzuki 1.6L Index Of Articles.

Here's a small sample of the 1.6L Suzuki tutorials you'll find in the index:

  1. How To Test The MAF Sensor (1992-1998 1.6L Sidekick).
  2. How To Test The Throttle Position Sensor (1996-1998 1.6L Sidekick).
  3. How To Test The Engine Compression (1.6L Suzuki Sidekick, Geo Tracker).
  4. 1996-1997 MAF Sensor Wiring Diagram (1.6L Sidekick / Tracker).
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Chevrolet Vehicles:

  • Tracker 1.6L
    • 1998, 1999, 2000

Geo Vehicles:

  • Tracker 1.6L
    • 1994, 1995, 1996, 1997

Suzuki Vehicles:

  • Sidekick 1.6L
    • 1993, 1994, 1995, 1996, 1997, 1998