Why Engine Valves Break
The following are some of the most common reasons why engine valves break. This information is courtesy of Basso S.A., a manufacturer of engine valves for original equipment and aftermarket customers.
Break between valve head and stem:
Cause: Repeated stress to valve stem
Contributing Factors:
- Weak springs
- Valve float
- Overreved engine
- Excessive lash
- Guide-to-seat misalignment
Break in keeper groove area:
Cause: Fatigue in the contact area between valve grooves and keepers
Contributing Factors:
- Damaged keeper groove
- Defective keeper assembly
- Valve float
- Excessive valve train clearance
- Overreved engine, especially on valves with rectangular keeper grooves
Break in middle of under head radius resulting in total valve head detachment:
Cause: Excessive engine load and accumulated heat
Contributing Factors:
- Overreved engine
- Valve float due to weak springs
- Too high seating speed due to excessive lash
Since the least common reason for valve failure is the valve itself, it is vital to determine and correct the cause of failure before replacing the valve, so the failure will not re-occur.
Bob Mitchell
Engine Pro
Technical Department
Economical Small Parts Cleaner, Degreaser
A good method to clean small parts (especially non-ferrous) is to mix equal parts of toilet bowl cleaner and water in a five gallon plastic pail. Make a strainer from another slightly smaller pail with holes drilled in it. Place parts in the strainer, immerse in liquid for 5 – 10 minutes depending upon the amount of dirt, then remove and rinse with water.
This will make brass and copper parts look like new!
Jim Kovach
Kovach & Assoc.
Performance Engine Building
Parma, OH
Oldsmobile V8 Crankshaft Turner
If you are on a budget or in a pinch when building an Olds V8 engine and need a quick and cheap crankshaft turning tool, use an “oil filter spin on” from a small block Mopar. They are the same thread and pitch, and usually have a 3/8? square in the center that a socket extension will fit into. This will work only clockwise.
Jeff “Beezer” Beseth
BeezerBuilt, Inc.
Newtown Square, PA
A Guaranteed Way To Grow Your Business
We’ve got a traditional machine shop customer in Kansas who has steadily grown his business without changing his business model. While many shops are lowering prices and spreading themselves thin by selling at low margins on the Internet or at swap meets, this guy keeps performing valve jobs and building stock replacement engines. His sales and profits grow at a modest, controllable rate year after year.
What’s his secret? There are actually two secrets to this owner’s success:
1. Customer Contact – He makes three sales calls per week. Every Tuesday, Wednesday and Thursday morning he leaves the shop at 9 a.m. to make one sales call. He arms himself with a brochure and a sticker. The brochure is a simple one page list of services and a bio on himself and his company. The 2? x 4? sticker gets stuck near the phone. It says, “Machine Shop – Auto, AG, HD” followed by the phone number and a space for the customer’s account number. He makes over 100 sales calls on garages, fleets, marinas and municipalities in 9 months!
2. Fair Prices – He prices his work based on his investment and expenses with enough left over to build a college fund for two kids and a retirement fund for he and his wife. He says most customers will pay a little extra to deal with his shop because of the personal visit and also his dedication to quality workmanship and use of quality parts.
Knowing your customers and your bottom line is a guaranteed way to grow your business.
Steve Rich
Sterling Bearing, Inc.
Kansas City, MO
Cleaning Piston Ring Grooves Before Re-Using
If you are doing a budget overhaul using the old pistons, here is a way to remove carbon from the ring grooves before re-ringing. Simply break one of the old compression rings in half and carefully use it as a scraper in the upper two grooves.
For the oil ring, hold it against one side of the ring groove walls and go around the piston, then do the same thing on the other side. Now you are ready to go ahead with your preferred method of degreasing the piston.
Brad Clarke
The Engine Shop
Morton, PA
Installation Tip For Oil Control Ring Expanders
When installing oil control ring expanders it is important to orient the expander with the “tips” pointing towards the crown of the piston. The reason for this is to eliminate the possibility for one of the expander 
tips wedging into the lower rail gap and hooking into a piston drainback slot. If this occurs, the oil ring assembly will not be able to rotate. The bottom rail and expander may bend and pull into the slot causing loss of oil ring function and potentially a catastrophic failure if the ring material is forced between the piston and cylinder wall.
Of course, the oil ring rail gaps should be offset from each other as well as the expander gap during installation and the assembly will then rotate in the groove as a three piece unit and without relative motion of the individual components.
Ira S. Rosenberg
Director of Engineering
Hastings Manufacturing Company
Hastings, MI
Engine Builder Shop Solutions is sponsored by Engine Pro,
a group of 9 engine parts specialist WDs in the U.S., and one in Australia, operating 35 branch
locations serving engine builders/rebuilders across the U.S and Australia. Shop
Solutions published in each issue of Engine Builder Magazine are a free one year membership to the Engine Rebuilders Council and a prepaid $100 Visa gift card. Winners will be chosen by
the staff of Engine Builder Magazine and the Engine Pro Technical
Committee.
To submit a Shop Solution simply mail your entry
to Engine Builder Magazine, Shop Solutions, 3550 Embassy Parkway,
Akron, OH 44333; or email to Shop [email protected]. Shop
Solutions may also be emailed to [email protected].
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your name, shop name, shop address and shop telephone number. Submitted
Shop Solutions not published will be kept on file and reevaluated for
publication with each month’s new entries. If you include your email
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