21 Pitch Prop vs. 19 Pitch Prop: Which Do You Need?
Owning a boat is similar to owning a car. Maintenance plays a crucial role in prolonging the lifespan of the vessel or vehicle. Without proper maintenance and the correct parts, there is a risk of things going wrong, sometimes with no prior warning. The propeller is the driving force of the boat. For this reason, it’s important to familiarize yourself with terms like propeller pitch and diameter. Choosing the right parts can help to lower the risk of issues, save you money and improve the performance of your boat.
In this informative guide, we’ll discuss 21 pitch prop vs. 19 pitch prop to help you decide which to buy for your boat.
What is propeller diameter and why is it important for boaters?
Propeller diameter is one of the most important specifications when replacing or repairing your boat propeller. The propeller diameter is a measurement, which covers the distance across the circle formed by the tips of the blades. In most cases, the larger the propeller, the slower the boat. The diameter of the propeller is influenced by the rpm (revolutions per minute).
Propeller diameter is important because it impacts speed and power. The diameter usually increases on slower boats and decreases on faster boats. A larger diameter has a bigger blade surface area, which provides more power for heavier vessels.
What is prop pitch?
If you’re a boating enthusiast, you have probably come across the term prop pitch. If you’re new to boating, this phrase may be less familiar. Prop pitch is short for propeller pitch. It is used to describe the distance the propeller would travel in a single revolution if it were moving through a soft solid material. The analogy of a screw moving through wood is often used to describe propeller pitch.
In the case of 21 pitch prop vs 19 pitch prop, the 21 pitch prop moves 21 inches through the soft solid material in one revolution. The 19 pitch prop moves 19 inches forward through the soft solid in a single revolution.
How will prop pitch affect my boat?
It is beneficial to understand the impact of prop pitch when choosing parts for your boat. To highlight the effect of the prop pitch, it’s helpful to imagine your propeller as the axle on a car. If the axle is lower, the car will have greater pulling power from a standing start. If the axle is higher, the car will reach higher speeds, but it will take longer to accelerate. A boat with a low pitch propeller will accelerate quicker than a high pitch propeller, but it will reach its top rpm at lower speeds. With a higher pitch prop, the boat will take longer to reach maximum rpm. This means that the top speed may be higher, but acceleration will be slower.
For every inch of pitch, you can expect to lose around 200 rpm.
21 pitch prop vs. 19 pitch prop: Which is best for my boat?
There is no universal answer to this question, and the best option will often vary according to the requirements of the individual. Here are some essential factors to consider when deciding between a 21 pitch prop and a 19 pitch prop:
Issues that affect your boat
Many people look to replace a propeller because they are having problems with their boat. Depending on the type of issue, one pitch prop may be more suitable than another. Examples of problems you may face include:
Sluggish to start
High fuel consumption
Excessive ventilation
Struggling to hit top speeds
If you want to increase acceleration, a lower pitch prop is best. If you’re eager to boost top speeds, a higher pitch prop may be best for your boat.
Under-revving vs over-revving
If you are under-revving or over-revving, this could increase the risk of damage to your boat engine. Your guide will include details of optimum revolutions for your boat. If you find that you are under-revving, it may be wise to choose a lower pitch propeller (19 pitch prop). If you are over-revving, buying a higher pitch prop (21 pitch prop) may be beneficial.
Why is it important to choose the right pitch prop?
Owning a boat requires ongoing maintenance. If you don’t take steps to preserve and protect your boat, you may end up spending a lot of money on repairs and your vessel might not last as long as it should. Choosing the right pitch prop for your boat is important for several reasons. Firstly, it can help to reduce the risk of engine wear, saving you money in the long term. Secondly, it’s critical to optimize performance and provide solutions for problems that you might encounter when taking your boat out. Thirdly, changing the pitch prop can help you customize your boat so that it caters to your preferences and requirements. If you use your boat for different activities or purposes, it is possible to buy two pitch props and switch between 21 and 19 pitch props.
Conclusion
Many boaters will reach a point where they are thinking about buying a new propeller. When looking for new propellers, it is hugely beneficial to be aware of the terms prop diameter and pitch prop. Choosing the right parts for your boat can help you lower the risk of engine wear and damage, enhance performance and tackle issues that are impacting the way your boat is running. If you are choosing between a 21 pitch prop and a 19 pitch prop, consider how you use your boat, the weather conditions, the speeds you want to reach and how fast you want to be able to accelerate. If you use your boat for a range of activities, or you enjoy traveling and you encounter different conditions, you could consider switching between 21 and 19 pitch props.