Johnson Service Bulletin SB-890 Revised - Ignition Systems
November 7, 1962. Revised specifications for testing ignition coils on the Stevens coil and condenser tester, covering Johnson engines from 1949 through 1963. This revision superseded the February 14, 1962 bulletin.
November 7, 1962
Bulletin No. SB-890
Revised to show 1963 usage
Ignition Systems
SUBJECT: Testing coils on old style Stevens Coil & Condenser Tester
containing ammeter, neon glow tube, and spark gap electrodes;
1949 thru 1963 engines.
This bulletin is for the benefit of those dealers who are using the subject Stevens
Coil and Condenser Tester.
These specifications apply only when using a 1/4" spark gap. When testing coils on
armature plates, condensers must be disconnected from coils or points.
Condensers are tested as described in the instructions provided with each testing unit.
over
SB-890
Page 2
* Coil must be mounted on a laminated core to test.
# Does NOT require special test adaptors of any kind with the subject test
equipment. See Service Bulletin #SB-844 for recommended procedures to
test on or off the engine.
## Either the 580197 or 580416 coils will be found in matched pairs on early
1962 - 18 h.p. engines. Coil identification can be determined as follows:
580197 has blue tinted plastic insulation.
580416 has purple tinted plastic insulation.
JOHNSON MOTORS
Robert Compton
Service Department
RC:eb
NOTE: Post on your Miscellaneous index
Destroy Service Bulletin #SB-890 dated 2/14/62.
Searchable 1963 coil-testing specifications
Transcribed engine applications and coil numbers from the November 7, 1962 revised factory chart. All amperage values shown are with heels. Use a 1/4-inch spark gap. Consult the original chart above and factory footnotes for testing precautions.
HP
Engine model(s)
Coil part number
Switch
Amperage (with heels)
2.5
HD(L)-25
375189
B
1.5 to 2.0
2.5
HS(L) and HD(L)-26
580118
A
2.0 to 2.5
3
JW(L)-10 through 18
580118
A
2.0 to 2.5
5
TD(L)-20
375189
B
1.5 to 2.0
5
TN(L)-25 and 26
375189
B
1.5 to 2.0
5
TN(L)-27 and 28
580118
A
2.0 to 2.5
5.5
CD(L)-10 through 20
580118
A
2.0 to 2.5
7.5
AD(L)-10 through 12
580118
A
2.0 to 2.5
10
QD(L)-10 through 11
580040
B
1.6 to 2.0
10
QD(L)-12 through 23
580118
A
2.0 to 2.5
15
FD(EL)-10, 10L and 10S
580118
A
2.0 to 2.5
16
SD(L)-15 and 20
375102
B
0.8 to 1.2
18
FD(EL)-11, 11K and 12; FD(L)-13 through 15F
580197
B
1.3 to 1.8
18
FD(L)-16
580197
B
1.3 to 1.8
18
FD(L)-16
580416
A
2.0 to 2.5
18
FD(L)-17
580416
A
2.0 to 2.5
22
PO(L)-15
72-852
B
0.8 to 1.3
25
RD(L)-10 through 17S; RDE(L)-16 through 17S
580118
A
2.0 to 2.5
28
RX(L)-10C through 11
580416
A
2.0 to 2.5
30
RD(EL) through RJE(L)-18 through 18C
580197
B
1.3 to 1.8
35
RD(EL) through RJE(L)-19 and 19M; RD(EL)-19C; RDS(L)-20; RD(SL)-21 and 21B
580197
B
1.3 to 1.8
40
RD(SL)-22 through 23
580197
B
1.3 to 1.8
40
RD(L) through RK(L)-24 and 25
580416
A
2.0 to 2.5
50
V4(SL)-10 through 11B
580243
B
1.5 to 2.0
75
V4S(L)-12 through 15
580243
B
1.5 to 2.0
75
V4A(L)-13 through 15
378231
A
1.0 to 1.5
Additional factory notes: coil 375189 requires a laminated core for testing. Coil 378231 does not require a special adapter with this tester. Early 1962 18 HP engines may use matched pairs of blue-insulated 580197 or purple-insulated 580416 coils. For SD(L)-15/20 the without-heels range is 1.0 to 1.3 A; for PO(L)-15 it is 1.0 to 1.5 A.
Related edition
The November 7, 1962 revision instructs dealers to destroy the earlier SB-890. The earlier version is retained here for historical comparison.
