Shindaiwa T2510 Service Manual page 14

7 Crankcase & Intake Sealing
Section
Testing For
Air Leaks
Inspecting
Intake Sealing
Points
15
When pressure testing, always use a new
plug, properly torqued.
STEP 9. To check crankcase seals and gasket
areas for leakage, maintain pressure in
crankcase and spray soapy water on
suspect surfaces. Observe. Formation of
bubbles indicates leakage.
STEP 10. If soapy water test does not reveal
leaking component, submerge pressurized
crankcase in water and observe. Air bubbles
will identify leaking seals or gaskets.
C. Confirm Intake Sealing
Air-tight Integrity of intake components is
critical for all aspects of engine performance.
Inspection points include:
Insulator block/reed valve
Carburetor casting (throttle side)
Cylinder casting at intake port
Mating surfaces should be smooth, perfectly
flat and free of cracks.
Check insulator block/reed valve to make sure
there is:
no warping or distortion
no cracking
no rough sealing surfaces
no pulled inserts/cast-in nuts
Always remove insulator block/reed valve
and inspect venturi/impulse side for cracking.
Cracks in this area are rare, but do occur!
Check venturi/impulse surface with a
straight-edge to assure that it is not warped.
Insulator blocks that are warped, but not
cracked, can often be salvaged by resurfacing.
Use emery cloth held to a flat surface, or a
wide, smooth, flat file. Clean mounting surface
carefully after resurfacing. Recheck with
straight-edge to make sure surface is true.
Intake sealing surfaces must be clean, smooth,
and perfectly flat to prevent air leaks.
Use a straight edge to assure that insulator
block mounting surfaces are true.
Reed valve assembly is permanently installed
on insulator reed block; must be replaced as an
assembly.
Integrity of carburetor mounting surface is
critical to engine performance.
Edition 2 • 09/2007