Maintaining your Porsche 944, especially the early models from 1984, requires meticulous attention to detail, particularly when it comes to the cam belt. Unlike later models with mechanical spring tensioners, early 944s demand a more nuanced approach to ensure correct belt tension. Improper tension can lead to catastrophic engine failure, including bent valves – a nightmare for any Porsche enthusiast. While the Workshop Manual (WSM) provides instructions, relying solely on them, especially with just a spring tensioner, can often lead to over-tensioning the cam belt. This is where a “Car Cricket Tool”, specifically a belt tension gauge like the Krikit II, becomes an invaluable asset.
Why Cam Belt Tension is Critical in Your Porsche 944
The cam belt’s job is to synchronize the crankshaft and camshaft, ensuring precise timing of valve openings and closings. Too much tension can stress the water pump bearing, potentially leading to premature failure. Conversely, insufficient tension can cause the belt to slip or jump teeth on the gears, resulting in severe engine damage. It’s not just about tension, though. A comprehensive cam belt service involves inspecting all related components for wear and tear.
Before even thinking about tension, it’s crucial to perform a thorough inspection:
- Roller Inspection: Examine every roller for signs of wear. Any roughness or play indicates a need for replacement.
- Water Pump Check: Grab the water pump pulley and attempt to tug, pull, and spin it. There should be no play and the rotation should be smooth. Early bearing failure here is a common issue.
- Oil Leak Inspection: Carefully check for oil leaks, especially from the crankshaft oil pump seal. Oil contamination on the belts is a recipe for premature failure. Porsche and Clarks Garage have even recommended changing the oil pump roller bolt on early cars or checking for movement as a preventative measure.
Moving Beyond Guesswork: Utilizing a Car Cricket Tool
While methods like the “90-degree twist” might offer a rough estimate, they lack the precision needed for such a critical component. To achieve accurate cam belt tension, a dedicated tool is essential. This is where the “car cricket tool”, or belt tension gauge, comes into play. The Krikit II is a popular and effective tool that allows you to measure belt tension precisely, taking the guesswork out of the process.
By using a car cricket tool, you can ensure that the belt tension falls within the manufacturer’s specifications, minimizing the risk of both over-tensioning and under-tensioning. After using your chosen tensioning method and tool, it’s wise to perform the Water Pump Pulley Test, as described in the original Porsche documentation.
The Water Pump Pulley Test: A Crucial Verification
Even with a tension gauge, the Water Pump Pulley Test provides an additional layer of security. With the engine at Top Dead Center (TDC), check the water pump pulley. Excessive belt tension can lead to premature water pump bearing and seal failure.
Post-Installation and Long-Term Maintenance
Remember, new belts require a settling-in period. Porsche recommends retensioning the new belts after approximately 1000 miles. This is a critical step often overlooked but essential for long-term reliability. Furthermore, adhering to a regular cam belt replacement schedule is cheap insurance. Many experienced Porsche owners, like Slam and others in online communities, advocate for changing the cam belt every 2 to 3 years, regardless of mileage. For a relatively low cost, this preventative measure can save you from potentially thousands of dollars in engine repairs.
When installing new belts, meticulously follow resources like the Clarks Garage belt change installation guide. Pay close attention to the balance belt roller orientation to prevent unwanted vibrations.
Tensioning your Porsche 944 cam belt, especially on early models, might seem daunting initially. However, by understanding the importance of correct tension, utilizing a “car cricket tool” for accurate measurement, and performing thorough inspections and maintenance, you can ensure the longevity and reliability of your prized Porsche engine. Investing in the right tools and knowledge is paramount for any DIY Porsche owner.
