How to use a Block Tester to check for a blown head gasket (combustion leak detector).

How To Use Block Tester In 4 Quick Steps

An engine block tester is a quick way to check for a blown head gasket on gasoline and diesel engines. Here you can check out how it works and the best ones to buy.

What Is A Block Test On A Car?

Firstly, the engine block is a large metal casting of an engine’s cylinders and pistons and is usually made from cast iron, aluminium, or steel. It is often called the “heart” of the engine. This is why the tool is called a block tester and put simply it quickly detects leaking exhaust gases into the engine cooling system.

Secondly, another important component of a combustion engine is the head gasket which sits between the engine block and cylinder head. Sometimes a block test is referred to as a head gasket tester. This gasket can deteriorate over time or if the engine overheats can be damaged which prevents it from sealing and keeping exhaust gases and coolant passages separate.

Finally, they can be used on any water-cooled engine like petrol, diesel, and LPG. They do one job and that is to test for combustion gases in the cooling system by the blue liquid turning a yellow colour if it comes into contact with exhaust gasses.

What Are Some Advantages?

They can be used to test the engine block of a car, or they can also be used to test an engine block in a machine. They work on any liquid-cooled internal combustion engine or generator with a closed engine cooling system including gasoline, diesel, propane, natural gas, and other alternative fuels. A great tool to have in your tool kit when buying a used car privately or just to have in your garage to test other combustion engines or generators.

They also, provide a quick and accurate way to test the integrity of an engine. They are also easy for anyone to use and do not require any special skills or training.

Quick And Easy Way To Check For Blown Head Gasket

If your daily drive has a loss of coolant but you just can’t locate any external leaks then you may fear the worst, a blown head gasket, cracked head, or block. Other symptoms may be the car is hard to start especially in the morning on cold-start. If your car overheats and you start to lose power then, of course, you don’t want to continue driving your car and risk doing other damage so you need to diagnose and get to the bottom of it quickly before you do further damage. If you keep driving this will cause the engine oil viscosity to change further destroying your engine.

So, if you own a vehicle and suspect loss of coolant it’s best to stop trying to guess and diagnose for certain if the vehicle has a combustion leak. The first thing to do is to use the following test wherever your car is parked. The sniff test will reveal if it has a cracked block or bad head gasket. On the tester, a bulb is pushed onto the end of a pipe to suck out any possible engine exhaust gasses. This makes checking for leaks a quick & easy process as shown below.

How To Do A Block Test In 4 Simple Steps?

How to use a Block Tester to check for a blown head gasket (combustion leak detector).

The combustion leak tester kits are simple to use:

  1. Siphon some coolant from the radiator so you don’t contaminate the test fluid
  2. Position the block tester to fit into the radiator
  3. Pump the bulb to see if the test fluid changes color from blue to yellow
  4. If the fluid changes color from blue to yellow this indicates a combustion leak

If it’s bad news at least you can then move forward with repairing or try using a quick head gasket repair. Also, make sure you do the test when you do an engine cooling system check before buying a car at an auction, dealer, or private seller. You can avoid unnecessary and costly repairs.

How Much Is An Engine Block Tester Kit?

(eBay affiliate links)

You can buy a combustion leak tester tool from eBay* (eBay affiliate link). For under $20 and can be a handy tool to have with you when you’re shopping for used cars. It can save you from buying another person’s problem saving you thousands in repairs.

Also, If you want to purchase a BT 500 block tester just be sure the test fluid comes with the kit and comes with a hard case for protection because they do get knocked around.

A complete block kit will ensure that you don’t need any other tools. The test fluid is good for about 16 tests and you can purchase replacement combustion leak test fluid bottles too.

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