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ASE A5: Brake Fluid and Bleeding Sequence

The ASE A5 Test includes a portion on brake fluid, bleeding, flushing and leak testing. You must know how to: • Diagnose poor stopping, pulling, dragging, or incorrect pedal travel caused by problems in the brake fluid; determine needed repairs. •...

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North Dakota Woman Goes From Daycare To Auto Repair

Everyone reading this, raise your hand if you ran a daycare before working in or owning an auto repair shop. Anyone? Well, that’s the story for Elyzabeth Goerger, who was recently profiled in North Dakota’s Prairie Business. Georger is the...

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South Dakota Tech Program Graduates In High Demand

The automotive repair industry, in certain pockets of the country, has a labor force problem. There either isn’t enough technicians to go around, or not enough properly trained technicians to go around. This isn’t the case in Sioux Falls, SD. What...

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Honda: Easy Fix for Engine Noise

We often encounter engines that have a cold-start knock or ticking noise. In this case, the 3.5-L V6 engines installed in various Honda models can make a knocking or ticking noise at idle and only when warm. The cause of the problem is that the rocker...

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Toyota: Rough idle, surging between 500 to 800 RPM

Model: 2005 Toyota Avalon and some models with similar system configurations, such as 2006 Camry models. Condition: The customer ­complains that the check engine light is on, rough idle and engine idle surging between 500 and 800 rpm. The technician...

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Volkswagen: Engine Does Not Start

Vehicle: 2001 Volkswagen Passat GLX, 2.8L Complaint: The customer says the vehicle will not start. Cause: Confirmed the customer’s complaint and found the vehicle did not start. Connected a scan tool and found the following codes: • 17978...

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Are You Chasing Weights?

It has happened to all tire techs, probably more than once. You balance a tire, put the weights on, drop the hood again for a check spin — and the balancer comes up asking for more weight. Fine. You add more weight, drop the hood and...it asks for...

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Cadillac CTS Alignment Spec

The first-generation Cadillac CTS was introduced in 2003 and ended production in the 2007 model year. The Cadillac CTS was built on GM’s rear-wheel drive Sigma platform. The CTS for years 2003-’07 came with two suspension packages­ — standard...

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Nissan Maxima Brake Job Tips

Called the four-door sports car by Nissan, the 2004-2008 Maxima brake system is easy to service with very few complaints of brake noise or pulsation. The system used the same brake pads, rotors and calipers on all models. There were some changes in...

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Midtronics Launches Informational Microsite

  Midtronics, Inc. has launched an informational microsite — or mini website — to provide customers with detailed information about the company’s newest diagnostic platform — the DSS-7000 Battery Service Diagnostic System. The microsite...

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German Tool Specialist KC Tool Announces Addition of Gedore Tools

As of August 1 KC Tool became the first certified reseller of Gedore Tools in the United States already adding more than 2,500 Gedore tools to its selection of German made tools. KC Tool plans to add an additional 6,000 Gedore Tools over the next few...

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United Stationers Expands Into Auto Aftermarket

United Stationers announced Sept. 11 that its wholly owned subsidiary, United Stationers Supply Co., signed an agreement to acquire MEDCO, a U.S. wholesaler of automotive aftermarket tools and supplies, and its affiliates including G2S Equipment de Fabrication...

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Home Cooling Oil Pumps & the Engine’s Lubrication System

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p can restore gear-to-gear clearances but not gear-to-housing clearances. The end plate that covers the pump often develops a heavy wear pattern that is most noticeable on the outlet gear side. Regrinding the face of the plate smooth can restore end play tolerances between the plate and gears but it can’t compensate for wear inside the housing. Deep scratches or grooves worn into the sides of the housing will leak oil and reduce the pump’s ability to move oil. In the case of front cover oil pumps on overhead cam engines, the pump turns at engine rpm and generates more flow at idle than crankcase-mounted pumps.

Consequently, when the pump becomes worn it isn’t always necessary to replace the entire cover assembly ‹ provided the pump housing inside the cover isn’t worn or damaged. A new drive gear can be mounted on the crankshaft and a new rotor installed in the cover to restore normal oil pressure. This approach eliminates the need to replace the entire cover assembly.

In cases where an engine has experienced a bearing failure or any other kind of internal failure that puts debris into the crankcase, the oil pump should always be replaced.

You should also replace the pump’s pickup tube and screen. Pickups are difficult to clean and can hide debris that may damage a new pump or the engine.

Pump Modifications
If you want to rework a stock oil pump to maximize flow, use a die grinder to smooth and blend the sharp edges of the pump inlet and outlet ports. This will reduce turbulence and enhance flow through the pump. The clearance between the end of the gears and the pump housing cover also should be minimized to reduce pumping losses around the ends of the gears. If you’re working on a small block Chevy V8, another trick that can boost oil flow is to install a big block Chevy oil pump instead of a small block oil pump. A stock big block Chevy oil pump has 12 teeth per gear versus seven for the small block version, and flows about 10% more oil at the same rpm.

Something else to watch out for when installing a high-volume oil pump in a small block Chevy V8 is the nylon retainer on the pump shaft. A better choice is a pinned steel retainer to provide extra support between the intermediate shaft and pump shaft.

Care must also be used when tightening down the pump mounting bolts on small block and big block Chevy V8s because the pumps do not use a mounting gasket. The bolts should be torqued to 60 to 70 ft.-lbs. so there are no leaks or sloppiness that would eventually cause the shaft to break.

Preventing Oiling Problems
The greatest oil pump in the world won’t keep an engine properly lubed if it is dry when the engine is first started, or if it sucks air because the oil level in the crankcase is low or the pickup screen is mounted too far above the floor of the oil pan.

The pickup tube should be installed so it is located no less than 3/8″ above the floor of the oil pan (to allow good intake flow), and no more than 1/2″ above the floor so it doesn’t run out of oil in a sharp turn. The pump should also be filled with oil when it is mounted on the block to prime it and reduce the risk of a dry start. Do not use grease or assembly lube here. In the case of front-mounted oil pumps inside the timing cover, the pump rotors can be coated with heavy oil such as 50W or even gear oil to keep the pump primed.

Before starting the engine, prime the oil system with a pressurized oiler.

Oil tends to drain off bearing surfaces when an engine sits for more than a week or so without running.

On older engines with distributor-driven oil pumps, the engine can be primed by using a drill to spin the oil pump shaft through the distributor hole.

But on engines with no distributor or those with oil pumps inside the front cover, this isn’t possible. Feeding pressurized oil into the main oil gallery through the oil pressure sending unit fitting will route oil to all the critical areas inside the engine and eliminate the risk of scuffing the bearings when it is first started.

Another option to consider is installing “coated” main and rod bearings if you’re replacing crankshaft bearings. Several major bearing suppliers have recently introduced performance engine bearings coated with a low-friction, moly-based anti-scuff surface treatment. The special coating increases the price of the bearings but provides added protection in the event of oil starvation.

Causes of Low Oil Pressure

Possible causes include:

  • Excessive main and rod bearing clearances (someone may have installed the wrong-sized bearings or standard-sized bearings on a reground crankshaft). Only 0.001″ of extra clearance in the main bearings can reduce oil pressure by up to 20%!

  • Excessive camshaft bearing clearances (a bearing may have slipped out of place when the cam was installed).

  • Excessive clearances inside the oil pump.

  • Leaks between the oil pump and engine.

  • Oil pump relief valve stuck open or installed backward.

  • A loose or mispositioned oil pickup tube (too high in the oil pan).

  • A defective oil pressure sending unit or oil pressure gauge.

  • Low oil level in the oil pan.

  • Cracks or leaks in the oil galleries or gallery plugs.

  • Cracked oil pump housing (improper installation).

  • Oil viscosity too thin for hot weather.

  • Oil viscosity too thick for cold weather.

Presentation Available on Engine Lubricant Quality

As vehicle maintenance professionals, you all are well aware of the importance of basic auto maintenance, especially the need to change lube oil and filters regularly. Over the past few years, we have seen not only major changes in automotive technology, but some say there also have been changes in the quality of engine lubricants. The net effect of these changes is that some engine oils that remain available in the marketplace are obsolete for modern engines, according to the Association of International Automobile Manufacturers (AIAM).

To receive a PDF version of a Powerpoint presentation developed by the AIAM that describes some of the excessive engine wear and sludge buildup problems that can occur when improper motor oils are used in modern engines, email us at [email protected] Please include your name, shop, location and e-mail address.

Oil Change Association Holds Convention

The Automotive Oil Change Association (AOCA) will be holding its “AOCA & All That Jazz Annual Convention & Fast Lube Expo” April 23-26 at the Ernest N.

Morial Convention Center in New Orleans.

The sixth-annual AOCA Boot Camp will be held on Saturday, April 23rd. This full-day program is designed to help new lube owners improve their operations and their bottom line.

Seminars include Getting and Keeping Customers; Add-On Services: Tire Rotation, Power Steering and A/C Service; Dude, Where’s My Car?; Warranty Claims ­ Self Defense and Customer Satisfaction; Working With the Media; and To Go of Grow.

On the exhibit floor, AOCA will host a new “demo theater” during which featured exhibitors will share their insights and techniques on cabin air filter service, water and deposit removal, training, car wash management, on-board diagnostics and the effects of thermal expansion on lube equipment.

For more information on AOCA and the convention, visit www.aoca.org or call 800-331-0329.

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Larry Carley

Larry Carley has more than 30 years of experience in the automotive aftermarket, including experience as an ASE-certified technician, and has won numerous awards for his articles. He has written 12 automotive-related books and developed automotive training software, available at www.carleysoftware.com.
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