Vanguard 25E300, Руководство по ремонту

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SPN 636 Crankshaft Wrong Tooth Number
Circuit Description
The CKP sensor works in conjunction with the 23X reluctor
target wheel on the flywheel. Each tooth on the reluctor
wheel is equally spaced with 1 tooth missing for the reference
sync pulse. As the crankshaft rotates, the reluctor target
wheel interrupts a magnetic field produced by an internal
sensor magnet. The CKP sensor is a Hall Effect sensor
and produces an ON/OFF DC voltage pulse when it detects
the magnetic field. The frequency of the CKP sensor output
signal is dependent upon crankshaft speed. The ECM uses
each CKP sensor output signal to determine crankshaft
speed and identify crankshaft position.
With the spark under control of the ECM, the engine will not
run if the CKP sensor signal is lost. The ECM will not be able
to determine which stroke the pistons are on.
Possible FMIs - SPN 636
The possible FMIs for SPN 636 are as follows:
FMI Description
2 Additional Edges Detected
8 Missing or Additional Tooth Detected
FMI 2 : Erratic signal possibly caused by excessive air gap or
electronic noise.
FMI 8 : Abnormal frequency due to excessive air gap or
metallic debris on sensor.
SPN 636, FMI 2: Not Enough Teeth Detected
Step Action Yes No
1 1. Turn Ignition OFF.
2. Check CKP sensor air gap.
3. Is CKP sensor air gap set at 0.010-0.015 inches (0.25-0.38 mm)?
NOTE: If air gap is too large, engine speed detection may be delayed
at slow speed. The engine may exhibit poor starting performance.
Go to step 2. Adjust as necessary.
2 1. Obtain a Briggs & Stratton Spark Tester (Part No. 84003327).
2. Install spark tester in line with ignition coil and spark plug.
3. Look for spark in tester windows while cranking engine.
4. Is spark observed? Go to step 3. Repair or replace spark
plug and/or ignition coil.
3 1. Turn Ignition OFF.
2. Check valve lash adjustment.
3. Is valve lash within specification? Go to step 4. Adjust as necessary.
4 1. Replace CKP sensor.
2. Is problem corrected? - Repair or replace
EFI wire harness.
43
Not for
Reproduction