Dashpot: Testing and Inspection
Dashpot System (M/T only) TestHOT ENGINE
NOTE: If the dashpot diaphragm in the throttle controller is damaged or vacuum to the dashpot diaphragm is blocked or leaks, correct idle speed can not be obtained. The idle speed will be excessively high after warming up the engine.
1. Connect a tachometer, start the engine and allow it to reach normal operating temperature (the cooling fan comes on).
2. Check that the idle speed is not excessively high.
- If the idle speed is within specification, go on to step 3.
- If the idle speed is excessively high, disconnect # 6 vacuum hose from the throttle controller and check for vacuum at the hose.
- If there is no vacuum, check # 6 vacuum line for leaks or blockage. Repair, clean or replace as necessary and retest.
- If there is vacuum, replace the throttle controller and retest.
3. With the engine idling, disconnect # 6 vacuum hose from the throttle controller.
Engine speed should rise to 1700 ± 300 rpm.
- If the rpm is not within 1700 ± 300 rpm, adjust by turning the adjusting screw.
- If the rpm does not change, check the throttle controller linkage for free movement.
- If there no problem, replace the throttle controller and retest.