Tech Tip: Piston Pin Spiro Lock Installation Procedures

When the locks are properly seated, only half of the lock will be visible above the groove. Most pistons that require spiral locks will need four locks per piston, two at each end of the pin (check with your piston supplier). When installing Spiro locks, grip each end of the lock and pull apart (approx. 3/8"-7/16"). The lock will resemble a small coil. The lock can then be spiraled into place almost as if you were screwing them into a groove.

Published: Oct 19, 2010

When the locks are properly seated, only half of the lock will be visible above the groove. Most pistons that require spiral locks will need four locks per piston, two at each end of the pin (check with your piston supplier).

When installing Spiro locks, grip each end of the lock and pull apart (approx. 3/8˝-7/16˝). The lock will resemble a small coil (Figure 1). The lock can then be spiraled into place almost as if you were screwing them into a groove (Figure 2).

WARNING: It is important that the correct numbers of locks are installed in each piston or severe engine damage may occur. Do not over stretch Spiro locks and do not reuse Spiro locks.

Tech Tip courtesy of JE Pistons.

Diagnosing Intercooler Boost Trouble Code P0299

The criteria for setting the code is very basic.

By Andrew Markel

Andrew Markel is the director of content for Underhood Service magazine. He has been with Babcox Media for 20 years. He is a technician and former service writer and holds several automotive certifications from ASE and aftermarket manufacturers.

Published: Apr 12, 2024

A code P0299 for lower- than-normal boost can be one of the most challenging DTCs to resolve. You might think it is a code for a leak, but it could be more than a leak. The criteria for setting the code is very basic. The engine management system is looking at the desired boost pressure and the actual boost pressure, if the actual and desired do not match for the conditions.