Because of its many two-stroke similarities, many of the C4's service functions are the same as Shindaiwa two-strokes. And, wherever possible, Shindaiwa used the same components and/or construction methods found on Shindaiwa two-strokes. Thus, for many service functions, such as carburetor...
2 Unique Components Section A. Crankcase: Parts That Distinguish The T2500 has a horizontally-split crankcase with upper half also comprising cylinder. The T2500 Bottom half contains boost port, reed valve, Powerhead and boost chamber cover. B. Cylinder: In addition to incorporating the upper crankcase half, the cylinder also has compartments for cam/gear assembly and overhead valve components (rocker arms,...
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Unique Components Section C. Crankshaft/Connecting Rod, Piston: Parts That Distinguish Forged three-piece crankshaft and connecting rod resemble two-stroke assemblies, but with The T2500 these key differences: (1) A metal timing gear Powerhead is pressed onto the recoil side, between main bearing and shaft end, and (2) the piston rings are not pinned.
D. Special Tools Some of the repair procedures described in this manual involve special Shindaiwa tools. These tools are identified by name and part number in the step-by-step explanations. A complete listing of all the special tools required for this product can be found in the "Special Tools"...
Valve Clearance Adjustment Section A. When To Adjust Tools/Specs Valve clearance should be checked and adjusted after 135 hours of operation, or as a possible remedy for low compression. Normal compression range for this engine is 90-125 PSI. (See master repair manual for test procedure and other causes of low compression.) B.
4 Valve Clearance Adjustment Section Pushrod Inspection (cont.) Inspecting Pushrod & Check for straightness by rolling pushrods across a flat surface, such as glass plate. If Cam Lobe any wobble is detected, replace. Check overall length with caliper or micrometer. Length should be 2.453" (62.3 mm).
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Valve Clearance Adjustment Section I. Adjustment Procedure Adjustment Procedure STEP 1. Remove cylinder cover, rocker arm cover, and set piston at TDC-compression (see point "H" above). STEP 2. (Optional.) To lock crankshaft/cam position at TDC-compression stroke, activate timing screw (see pg. 12). STEP 3.
5 Servicing Pushrods/Followers/Cam Section A. Remove Pushrods Removing & Installing STEP 1. Remove rocker arm cover. Pushrods, STEP 2. Rotate crankshaft so that piston is at Rocker Arms top-dead-center (TDC) of compression stroke (cam lobe facing down). & Followers NOTE: To identify TDC-compression vs.
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Servicing Pushrods/Followers/Cam Servicing Pushrods/Followers/Cam Section Section F. Install Cam Followers Reverse steps above to in stall followers. IMPORTANT! Install left-hand (intake valve) follower first. G. Remove Cam Gear Removing & Installing STEP 1. Remove pushrods and followers. Cam Gear STEP 2. Remove cam axle pin. STEP 3.
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6 Reed Valve Inspection/Replacement Section A. Reed Valve Locations Inspecting & Replacing The T2500 engine relies on two steel reed valves as a key element of its C4 technology. Reed Valves The intake reed valve is mounted on the back (engine) side of the insulator block.
Crankcase & Intake Sealing Section A. C4 Crankcase Principles Crankcase Sealing Shindaiwa C4 engine technology relies on a sealed crankcase, just like a two-stroke. That Principles means air leaks can lead to serious operational problems, just like they do in two-strokes.
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7 Crankcase & Intake Sealing Section When pressure testing, always use a new Testing For plug, properly torqued. Air Leaks STEP 9. To check crankcase seals and gasket areas for leakage, maintain pressure in crankcase and spray soapy water on suspect surfaces.
Inspecting Impulse Passage Section A. Impulse Function Critical Checking Impulse Like a two-stroke, the T2500 C4 engine relies on crankcase impulses (positive/negative Passage pressure) to operate the carburetor's fuel pump diaphragm. Impulses are delivered to the carburetor through a passage in the insulator block/reed valve component.
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9 T2500/T2510 General Specifications Section COMPONENT: SPECIFICATION: ENGINE T2500/T2510 Displacement 24.5 cc / 1.48 cu. in. Bore/stroke 34 mm X 27 mm Horsepower 1.1 HP RPM @ maximum HP 8000 HP Maximum no-load RPM 10,500 RPM Weight (less accessories) 11.3 lb. / 5.1kg Specific output (cc per hp) 22.3 cc per HP...
T2500 General Specifications Section RECOIL Housing material Nylon Attachment points Cord diameter 3 mm Cord length 700 mm / 27.5 in. IGNITION Ignition t ype STCI (2510: PCI with rev limiter) Components Minimum output voltage 18 kV Coil wire Replaceable: 6 mm x 75 mm Coil/flywheel air gap 0.012"-0.014"...
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9 T3410 General Specifications Section COMPONENT: SPECIFICATION: ENGINE T3410 Displacement 34cc/ 2.1 cu. in. Bore/stroke 38 mm X 30 mm Horsepower 1.4 HP RPM @ maximum HP 8000 HP Maximum no-load RPM 10,500 RPM Weight (less accessories) 12.9 lb. / 5.8 kg Specific output (cc per hp) 24.3 cc per HP Idle RPM...
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T3410 General Specifications Section RECOIL Housing material Nylon Attachment points Cord diameter 3 mm Cord length 700 mm / 27.5 in. IGNITION Ignition t ype STCI (2510: PCI with rev limiter) Components Minimum output voltage 18 kV Coil wire Replaceable: 6 mm x 75 mm Coil/flywheel air gap 0.012"-0.014"...