Troubleshooting; Engine Overspeeding; Engine Surging; Service - Tecumseh TC 200 Technician's Handbook

TROUBLESHOOTING

ENGINE OVERSPEEDING

1. If the engine runs wide open (faster than normal), shut the engine off or slow it down immediately.
2. Visually inspect the air vane, linkage, carburetor throttle shaft, and speed control for debris blockage, binding,
breakage, or incorrect hook-up. Check the governor spring for a stretched or distorted condition. Remove the recoil
assembly and / or fuel tank if necessary. See "Disassembly Procedure" in Chapter 7.
3. Clean, correct or replace binding or damaged parts. Set the speed control to the recommended engine R.P .M.

ENGINE SURGING

1. Try to stabilize the engine R.P .M. by holding in one position the carburetor throttle shaft on the exterior of the
carburetor.
2. If the engine R.P.M. stabilizes, the governor or governor adjustment should be checked. Follow the procedure under
"Governor Adjustment" in this chapter. If the engine R.P .M. does not stabilize, the engine will require additional
checks see Chapter 3 under ''Troubleshooting".
3. If the problem persists after the governor adjustment, check the engine R.P .M. found on microfiche card # 30 or in
the computer parts lookup. If the setting for high and low speed are within the listed specification and a slight surge
is
experienced, increasing the engine idle speed slightly may eliminate this condition.
4. Visually inspect the air vane, linkage, carburetor throttle shaft, and speed control for debris blockage, binding,
breakage, or incorrect hook-up. Check the governor spring for a stretched or distorted condition. Remove the recoil
assembly and/or fuel tank if necessary. See "Disassembly Procedure" in Chapter 7. Repair or replace as necessary.

SERVICE

For governor disassembly or assembly procedures see
"Service" in Chapter 7.

GOVERNOR ADJUSTMENT

Three different styles of governor systems are used on TC
engines. Use the following illustrations (diags. 4-3, 4-4
and 4-5) to identify the governor system used and the
following procedure to adjust the governed engine speed.
1. Allow the engine to run for at least 5 minutes to reach
the operating temperature. Make sure the air filter (if
equipped) is clean and the choke is in the off position.
2. Using a Vibratach (part # 670156) or other tachometer,
determine the engine's R.P.M at idle and wide open
throttle. Consult microfiche card # 30 or the computer
parts lookup to obtain the recommended engine
speeds.
3. Using the applicable illustration, either bend the speed
adjusting lever toward the spark plug end of the
opposite direction to increase R.P .M. On TC Type II
engines, turn the speed adjusting screw out to
increase or in to decrease engine high speed R.P .M. If
adjustment screw is turned out to increase the engine
R.P .M., the speed control lever must be moved to allow
the speed control plunger to contact the speed
adjustment screw.
4. The low speed is set by moving the throttle control to
the lowest speed position and adjusting the low speed
adjustment screw on the carburetor.
TYPE I
Spring Hooked
In Notch
TYPE I
Spring Hooked
In Notch
Speed
Adjusting
Lever
Decrease Increase
Ý
Speed
Adjusting
Lever
4-3
17