Technical data

13773-001
74-00
Page 4 30 Nov 2000
Rough Running or Vibration in
Specific RPM Range
Magneto internal component
failure:
(Refer to TCM Ignition Systems
Master Service Manual) Specifica-
tions and inspection procedures.
Points Inspect for excessive burning, pit-
ting, corrosion, gap setting, and
general condition.
Cam Inspect cam for excessive wear or
unevenness that could cause
“point spread”.
Condenser Inspect for faulty P-lead connec-
tion, P-lead stud for overtorqued
condition, damaged pigtail con-
nector, and integrity of windings.
Coil Inspect for cracks, damage to high
tension strap or pigtail connector,
and integrity of windings.
Distributor Gear Inspect electrode finger for loose-
ness, gear teeth, and shaft.
Inspect carbon brush for damage.
Distributor Block Inspect distributor towers for evi-
dence of abrasion or excessive
burning. Examine rotor gear bush-
ings for wear.
Excessive RPM Drop During Mag-
neto Check
Incorrect external timing to engine. (Refer to TCM Model IO-550 Over-
haul Manual) Correct as required.
Incorrect internal timing. (Refer to TCM Ignition Systems
Master Service Manual) Correct
as required.
Fouled spark plugs. Clean spark plugs according to
manufacturer’s specifications.
Incorrect spark plug gap. Regap spark plugs to engine man-
ufacturer’s specifications.
Faulty spark plug. test spark plug in accordance with
manufacture’s specifications.
Faulty tachometer. Confirm tachometer accuracy at
RPM where magneto drop noted.
Correct as necessary.
Faulty ignition lead. (Refer to TCM Ignition Systems
Master Service Manual) Ignition
lead troubleshooting information.
Trouble Probable Cause Remedy