Understanding how to properly disassemble your Stihl BG-86 blower is a valuable skill, whether you’re tackling routine maintenance, a stubborn repair, or simply performing a thorough cleaning. This guide will walk you through the process, component by component, ensuring you can confidently take apart your trusted machine. From essential safety precautions to carefully removing intricate parts, we’ll cover the necessary steps to gain access to the engine, carburetor, and other critical areas. Learning to safely and effectively take apart your blower can save you money on professional repairs and extend the life of your equipment. Always remember that careful documentation and organized storage of parts during disassembly will make the reassembly process significantly smoother. Let’s get started on bringing your BG-86 back to optimal performance.
Safety first and gathering your tools
Before you begin any work on your Stihl BG-86, safety must be your absolute priority. Power equipment can be dangerous if not handled correctly. Start by ensuring the engine is completely cool to prevent burns. Next, and most critically, disconnect the spark plug boot from the spark plug. This prevents any accidental engine starts while you’re working. It’s also wise to drain any fuel from the tank into an approved container, reducing the risk of spills and fire. Always work in a well-ventilated area.
Once safety precautions are in place, gather the necessary tools. Having everything at hand will make the process much more efficient. For the BG-86, you’ll primarily need:
- Torx drivers (T20, T25 are common for Stihl equipment)
- Flathead screwdriver
- Pliers (for fuel lines and clamps)
- Spark plug wrench (if removing the spark plug)
- Small socket set (for some nuts, if applicable)
- Shop rags or paper towels
- A container or magnetic tray to organize screws and small parts
- Safety glasses and work gloves
Removing external components
With your safety gear on and tools ready, you can begin the disassembly process by removing the more accessible external components. These parts often need to be moved to gain access to internal systems.
- Air filter cover and filter: Locate the clips or screws securing the air filter cover. Remove them, then carefully pull out the air filter. This provides initial access to the carburetor area.
- Blower tube: The main blower tube is usually secured by a clamp or a simple twist-lock mechanism. Disengage it and set the tube aside.
- Starter housing (recoil assembly): This is the component you pull to start the engine. It’s typically held in place by several Torx screws on the top of the engine. Remove these screws and carefully lift the starter housing away. Be mindful of any spring tension or linkages if it doesn’t lift easily. This exposes the flywheel.
- Fuel tank: The fuel tank might be attached to the main housing with a few screws. Before lifting it, you’ll need to carefully disconnect the fuel lines from both the carburetor and possibly the primer bulb, using pliers if necessary for hose clamps. Ensure any remaining fuel is drained.
- Spark plug boot and spark plug: If you haven’t already, ensure the spark plug boot is disconnected. Using a spark plug wrench, remove the spark plug itself. This step is crucial if you later need to use a piston stop tool to remove the flywheel or clutch.
Accessing the engine and carburetor
Now that the exterior components are removed, you can delve deeper into the core of your Stihl BG-86, focusing on the engine and its fuel system. This stage requires a bit more precision and attention to detail, especially when dealing with delicate linkages.
- Carburetor cover and linkage: After removing the air filter, you’ll typically see a plastic cover protecting the carburetor. Remove any screws holding this in place. Once the cover is off, you’ll gain full view of the carburetor. Carefully observe and disconnect the throttle linkage and any choke linkages from the carburetor. It’s often helpful to take a photo before disconnecting to aid reassembly.
- Fuel lines from carburetor: With the linkages free, gently pull the fuel lines off the carburetor’s inlet and return ports. Be prepared for a small amount of residual fuel.
- Removing the carburetor: The carburetor itself is usually secured by two nuts or screws that pass through an intake manifold or insulator block, attaching it to the engine. Remove these fasteners. You may need to gently pry the carburetor off its mounting studs, being careful not to damage any gaskets or O-rings underneath. Inspect the intake manifold gasket for damage.
- Muffler removal: The muffler is typically attached to the engine cylinder by two or three screws or nuts. Remove these fasteners. The muffler might be slightly stuck due to carbon buildup, so gentle wiggling may be required. This step often exposes the exhaust port and the piston for inspection.
- Engine shroud/blower housing: This larger plastic housing often encompasses the engine cylinder and directs cooling air. It is usually secured by several Torx screws around its perimeter. Remove these to fully expose the engine and its components.
Common BG-86 Issues and Related Disassembly Steps
| Issue | Relevant Disassembly Steps | Typical Tools Needed |
|---|---|---|
| Blower won’t start | Spark plug, Carburetor, Fuel lines, Air filter | Spark plug wrench, Torx drivers |
| Loss of power | Air filter, Carburetor, Muffler (for carbon buildup) | Torx drivers, Carburetor adjustment tool (if cleaning) |
| Fuel leaks | Fuel tank, Fuel lines, Carburetor gaskets | Torx drivers, Pliers |
| Recoil starter problems | Starter housing | Torx drivers |
| Excessive vibration | Fan/impeller, Engine mounting bolts | Torx drivers, Socket set, Impeller wrench |
Separating the engine and fan assembly
The final stage of deep disassembly involves separating the engine from the main chassis and, if necessary, disassembling the fan or impeller. This step is often undertaken for major engine repairs or to replace the impeller itself.
- Engine mounting bolts: The engine unit is typically secured to the main plastic chassis or frame of the blower by several bolts. These are usually Torx screws and can be found around the base or sides of the engine where it interfaces with the housing. Remove these bolts.
- Separating the engine: Once all mounting bolts are removed, the engine should be able to separate from the main housing. You might need to gently pry it apart, ensuring no hidden wires or hoses are still connected.
- Removing the fan/impeller: If you need to access the crankshaft or replace the fan (impeller), this is the next step. The fan is usually threaded onto the crankshaft. Important: The fan often has a reverse thread (left-hand thread), meaning you turn it clockwise to loosen. You will likely need to prevent the crankshaft from turning by using a piston stop tool (inserted into the spark plug hole) or by carefully wedging something against the flywheel. Once the crankshaft is secured, use an appropriate wrench or tool to unscrew the impeller.
- Removing the clutch (if applicable): Some BG-86 models might feature a centrifugal clutch. If present and requiring removal, it will be threaded onto the crankshaft, typically behind the fan. Like the fan, it might also have a reverse thread and will require a special clutch tool or an impact wrench for removal, while still preventing the crankshaft from rotating.
Successfully disassembling your Stihl BG-86 blower is a rewarding accomplishment, providing deep insight into its mechanics and enabling various repairs and maintenance tasks. We’ve navigated through the critical initial safety precautions, systematically removed external components, accessed the engine and carburetor, and finally separated the engine and fan assembly. Each step emphasized careful handling and proper tool usage. Remember that organization during this process—keeping screws and parts grouped and possibly labeled—is paramount for a smooth reassembly. Whether you were cleaning, replacing a worn part, or troubleshooting an issue, this guide should empower you with the knowledge to maintain your blower more effectively. Regular maintenance and understanding your equipment’s components are key to ensuring its longevity and reliable performance for many seasons to come. Always refer to your owner’s manual for specific torque settings and detailed diagrams during reassembly.