How Diesel Engine Turbochargers Work

How Diesel Engine Turbochargers Work

Mechanic Notes:  A diesel engine is 'dead in the water' without the turbocharger. High pressure atomized diesel injection needs maximum air intake boost to operate efficiently. You'll know when the turbo is not working up to speed, the smoke show out the tail pipe will be the obvious sign.

 Mechanic Checks for A Turbocharger Problem
If you suspect a turbocharger problem and the diesel engine you're working on is a mechanical model you can check the boost pressure which should be around 20 p.s.i.

Take the reading off of the intake manifold with the engine at full throttle and full load. Hook up a line and go for a road test and make sure you get a nice heavy pull on the engine. The next step is to remove the intake side of the turbo (easier than the exhaust side) and check the compressor wheel and shaft for any movement and wear or signs of engine oil in the piping.

The air induction system includes the air filter and piping which must not be overlooked. Simple steps include checking for a restriction in the air filter and visually checking out the piping for loose clamps and perforations. The first sign of a hole in the piping or a loose clamp will be a high pitched whistle, not to be confused with the characteristic whine that comes from a turbocharger under load.

 This is a common problem and can be checked by setting the park brake (set wheel chocks as an extra precaution), foot brake on, transmission in gear and throttling up the engine RPM enough to feel a load. You'll need assistance with this test so you can look and feel for leaks.

Electronically controlled diesel engines will most likely flash a trouble code on the dash which requires diagnosis with a laptop / software. The modern day Mechanic needs software and a laptop...if you don't have these tools you're going to go down fighting.

Here's an excellent video tutorial on how the turbocharger works. Check it out!

Air Brake Theory Revealed

Here is an excellent video on air brakes. This is the best presentation I've ever seen that will give you a detailed overview on exactly how air brakes work. The air brake mechanical and air systems work together. This video is referring to a school bus but is the same brake system found on most transport vehicles.



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The cutaways and detailed views of the air brake system explained here will help you understand the principles and terminology that you need to know. There are many things that happen in air brake systems like moisture that builds up from the heat that is generated from the compressor.

This is why draining air tanks daily is very important especially in cold weather conditions. This is a lot of information to absorb but the power of video allows you to watch it more than one time.

Deutz Engine Assembly - Animated Version

Deutz Engines are a quality engine and here is an amazing animated video showing the assembly of an automotive 4 cylinder model. I believe this one is a 2.0 Litre displacement. You'll notice the double overhead cam construction which is run off a timing chain run off the crankshaft. This looks easy with fancy graphics but don't be fooled!


I would love to have this type of software when assembling an engine especially a Deutz Engine Assembly.

Haldex Brakes-Self Adjusting Slack Adjusters

Haldex Brakes self adjusting slack adjusters are installed at the factory on all Thomas Buses equipped with air brake systems. This allows much better control over brake adjustment especially for a large school bus fleet operation. At the same time there are operating and maintenance procedures that must be followed to get the best performance out of Haldex Self Adjusting Slack Adjusters.

Here Are Some Important Maintenance Steps To Follow:

• Visual and operational checks must be made at every scheduled PM check
• Check adjusters and anchor brackets for visual damage
• Automatic Adjusters should not be operated as manual adjusters
• Standard chasis grease may be used to lubricate Haldex Slack adjusters
• Lubricate the Standard 409-10 model every 50,000 miles or 3 mths
• Lubricate Reduced Maintenance 409-10 once a year
• No-Lube 429-10 adjusters are sealed and do not require lubrication
• DO NOT use Moly-disulfide grease as this will effect the operation of the slack adjuster
• Replace the slack adjuster if the TORQUE is less than 13 ft lbs when backing off the adjuster. You will hear the ratcheting sound while doing this.
• Haldex Slack Adjusters should be checked for operation between 90-100 p.s.i. in the air brake system reservoir. Anything over 100 p.s.i. starts to measure deflection in the foundation brakes and does not give a true reading
• To self adjust Haldex Brakes the operator has to make several full brake applications [spring brakes released] preferably with brakes hot and over 90 p.s.i in the air brake reservoir.
  
  Here is a very good video explaining proper Brake Adjustment on an air brake system. The self adjusting slack adjuster in this video is not a Haldex but the exact same procedure applies. In my experience with a properly adjusted Haldex slack adjuster the push rod travel averages at 1.5 inches of travel. Well below the Department Of Transport maximum allowed brake adjustment specs.
  
  Self adjusting slack adjusters are now standard equipment on all Thomas Buses and are a real asset for large fleets who must keep up with Department Of Transport Standards especially with air brakes and proper adjustment. I hope this post has informed you on the proper maintenance of Haldex Brakes.

Cat 3116 Engine Synchronization Video Tutorial

Cat 3116 Diesel Engine Setting Synchronization is a multi-step operation and requires the Cat Tune up Kit. Some standard hand tools will work but most of the setting tools are specially designed for this purpose. NOTE: Remove fuel solenoid before starting synchronization, this allows free rack movement.

Below is Step One:

Calibrating #1 Injector




Step Two:

Setting Up For Injector Synchronization



Step Three:

How To Adjust Injector Synchronization



This is the hardest step to get around {especially for the first time} but comes much easier with repetition. The Cat 3116 Diesel Engine is a fussy engine to tune up but it pays you back with great performance.