Mazda Miata Crank Wobble/Mazda B Series Engine
A common issue with the early Mazda Miata is a failure of the crank pulley, which causes a loss of power, loss of throttle response, and other poor running conditions.
This issue, in the Miata owner's world, is often thought as being a problem specific to the early Miatas. Specially the '90-Dec. '91 Miata with the 1.6l motor. It was thought to be due to improper design of the timing gear pulley and how it interfaces with the crankshaft. However, as the video below will explain, there is another issue that seems to be the real cause of the problem. That issue is improper timing belt installation.
Since the Mazda B series motor was widely used across Mazda, Ford, and Kia, this issue has the potential to show up in several cars. Listed below are a few examples of possible cars that may see this issue, but it is not a complete list. This list covers long year spans, because even though the engines and sizes may change with new model years of certain cars, the basic crank design remained similar.
This issue, in the Miata owner's world, is often thought as being a problem specific to the early Miatas. Specially the '90-Dec. '91 Miata with the 1.6l motor. It was thought to be due to improper design of the timing gear pulley and how it interfaces with the crankshaft. However, as the video below will explain, there is another issue that seems to be the real cause of the problem. That issue is improper timing belt installation.
Since the Mazda B series motor was widely used across Mazda, Ford, and Kia, this issue has the potential to show up in several cars. Listed below are a few examples of possible cars that may see this issue, but it is not a complete list. This list covers long year spans, because even though the engines and sizes may change with new model years of certain cars, the basic crank design remained similar.
- 1985-1994 Mazda 323
- 1987-1996 Mercury Tracer
- 1991-1993 Mazda MX-3
- 1989-2005 Mazda Miata
- 1995-2004 Kia Sephia RS, LS, GS
- 2000-2005 Kia Rio
- 1990-2004 Mazda Protege LX, EX, PR-5
- 1995-1998 Mazda Protege ES
- 1991-1996 Ford Escort GT and LX-E
It's also important to remember that since this issue shows up due to improper maintenance techniques, it is not isolated to this engine design, or the certain manufacturers. While HPMotors sees this issue the most on Miatas, that's simply because we work on lots and lots of Miatas. This type of problem is something we've seen on completely different makes and models, but the issue is still often due to the same improper maintenance methods causing the failure.