Tech Notes

GM Belt Tensioner May Cause Supercharger Failure

Problem: Premature failure of supercharger bearings. Cause: When the belt tensioner starts to fail, belt tension...

General Guidelines for Adjusting Brass and Nitrophyl Floats

The two methods of adjustment are internal (dry) setting and the external (wet) setting. The internal float adjustment is accomplished with the fuel bowl...

What You Need To Know About SBC Port Volumes

A 4-cycle engine is far from being a simple air pump. The principle reason turning apparent simplicity into real world complexity is the dynamic...

Connecting Rod Installation Basics

Here is some good, basic information about how to properly install connecting rods. Step 1:     Apply the...

Chrysler 2.4L Cylinder Block Casting Identification

Chrysler replaced its old SOHC four cylinders with an all-new family of SOHC and DOHC engines in 1995. There were 2.0L SOHC and DOHC...

Oil Seepage From Back of Cylinder Head on Mercedes M272/273 Engines

If you receive customer reports of oil seeping from Mercedes vehicles equipped with M272/273 engines, the cause could be the round plastic expansion plugs...

Valve Failure Analysis: Impact and Fatigue

Since the least common result of valve failure is the valve itself, it is always necessary to determine the cause of failure prior to...

Use Simple 10-second Check to Avoid Three Common Valve-Lock Problems

By Fergus OgilvyAssemble the valve locks on a valve and using your thumb and forefinger raise the retainer to its full height....

Tips For Selecting a Carbureted Intake Manifold

Performance intake manifold manufacturers offer several different options to get air and fuel from carb to heads. The secret is choosing the right intake...

Multiple Cylinder Misfire or Rough Idle on 2004-’06 Chrysler 3.5L Engines

This bulletin involves rotating all ­engine exhaust valves, replacingthe valve spring retainer locks with a new design to increase valverotation at lower rpm, inspecting/replacing...

Oil Leak Repair for 1990-1993 4.0L Ford V6 Engines

The most common oil leak on ’90-’93 4.0L engines is often diagnosed as a rear seal leak, but in most cases, the problem is...

Motor Oil Fact or Fiction

1. Synthetic motor oil is too slippery. It causes roller bearings to slide instead of roll, and that causes the bearings to fail.

Engine Whine Sounds at Idle Reported on Some Chrysler 6.1L Engines

This bulletin applies to Chyrsler models equipped with a 6.1L engine with an engine serial number of TNXE6026620001 or less. Theengine serial number can...

Chrysler 3.7L Throttle Body ‘Whistle-Like Sounds’

This repair procedure involves applying a thin bead of RTV to theintake manifold-to-throttle body joint.This information applies tovehicles equipped with a 3.7L engine built...

Destroking or Decompressing Pistons

The clearance inside the combustion chamber is reduced when the engine block surface or cylinder head surface has been resurfaced. The reduced combustion chamber...

Oil Leak From Front Timing Cover Reported on Some 2005-2006 Toyota 2GR-FE Engines

Use the repair procedure below to diagnose and correct this condition. Repair Procedure1. Inspect the location where the Bank 1 cylinder...

Why Replace Oil Pump Intermediate Shafts?

The material worn off all goes to the oil pan where some is washed out during the oil changing process, but a portion goes...

Audi/Volkswagen 1.8L DOHC Gasoline Engine Valve Failure Caution

Reviews of these problems, which are leading to breakage of the valves, and in some cases catastrophic failures, are related to problems not with...

Advantages of Using an Aluminum Flywheel

By Sam Logan Using aluminum sheds 10-15 lbs. from the rotating assembly of a conventional steel flywheel, but it is the effect...

Phaser-Style Variable Valve Timing System Controls and Operation

By Matt Dixon, assistant professor, Southern Illinois University Vehicles with variable valve timing (VVT) have become commonplace over the last decade. Even more commonplace are...