DescriptionThis video provides step-by-step repair instructions for replacing the pump diaphragm on a Honda small engine. The most common reasons for replacing the pump diaphragm are when the engine won’t start or is leaking fuel.
All of the information for this pump diaphragm replacement video is applicable to the following brands:
Honda
Tools needed: 8mm socket or nut driver, small flat-head screwdriver
Step-By-Step Instructions1
Before you replace the pump diaphragm in your engine’s carburetor first make sure the engine has cooled.
2
Now depress the tabs to release the air filter cover and pull out the filter element.
3
Use an 8mm socket or nut driver to unthread the mounting nuts securing the filter housing.
4
Remove the support plate and detach the housing from the breather tube.
5
Note the orientation of the fuel lines attached to the carburetor then detach them – be prepared for some fuel to spill out.
6
With the lines detached, slide the carburetor off of the mounting posts. and set it on a sturdy surface.
7
Use a phillips-head screwdriver to remove the screws holding the carburetor components together.
8
Carefully lift off the needle housing, metering cover and mounting plate assembly.
9
If still intact, separate the old diaphragm from the pump gasket.
10
When installing a new pump diaphragm we recommend using a new gasket as well.
11
Confirm that the spring is in place then align the gasket on the tabs along with the new diaphragm.
12
Reposition the needle housing, metering cover and mounting plate assembly.
13
Thread and tighten the screws to secure.
14
Confirm that the mounting posts are fully extended and slide the carburetor onto them.
15
Attach the fuel lines to the appropriate ports on the carburetor.
16
Confirm that the O-ring is in place in the air filter housing then reposition the housing by inserting the port into the breather tube as you align the housing on the posts.
17
Replace the support plate then thread and tighten the mounting nuts to secure the assembly.
18
Replace the air filter element.
19
Realign the air filter cover and snap it into place.