Spark Plug Time-Sert Kits

Specialized kits for 10mm, 12mm, 14mm, and 18mm spark plug threads. The professional choice for permanent spark plug thread repair.

SPARK PLUG KITS

WASHER SEAT

Washer seat spark plugs
seal with a washer on plug.

WASHER SEAT INSERTS

TAPER SEAT

Sealer must be used when
installing taper seat inserts.

TAPER SEAT INSERTS

KIT
SIZE

PART
NO.

LENGTH
MM

PART
INCHES

PART
NO.

LENGTH
MM

PART
INCHES

PART
NO.

1/4-32

RC engines

0142SP

4.5

.180

01421

M10 X 1.0

Standard kit

4010

9.0

.360

40101

M10 X 1.0

Deep Hole Kit

4010E

12.0
15.0
23.0

.472
.600
.905

40102
40103
40105

M10 X 1.0

GLOW PLUG

4010GP

12.0

.472

40102

M10 X 1.25

GLOW PLUG
DuraMax 6.6L Diesel

4024

16.2

.650

10123

M12 X 1.25

4212

9.0
15.0
17.5
22.0

.360
.600
.690
.866

42121
42123
42125
42127

M12 X 1.25

2008 FORD
3 VALVE

4212H

21.0

.827

42126

M14 X 1.25

Standard Kit

4412

7.0
8.0
9.4

.270
.320
.370

44121
44123
44125

7.0
10.0

.270
.400

44181
44183

M14 X 1.25

Deep Hole Kit

4412E

11.0
13.5
15.0
16.8
23.0

.430
.530
.600
.660
.905

44127
44113
44129
44111
44112

13.5
15.7
16.8
24.0

.530
.620
.660
.950

44184
44185
44186
44187

M18 X 1.5

4815

10.0
18.3

.400
.720

48151
48153

10.0

.400

48181

7/8-18

4718

11.0
20.0
24.5

.430
.780
1.000

47181
47183
47185

M14x1.25
Aluminum Inserts

WASHER SEAT

INCHES

PART
NO.

TAPER SEAT

INCHES

PART
NO.

Aluminum Inserts

For kits 4412 & 4412E

7.0

.270

44121A

7.0

.270

44181A

8.0

.320

44123A

10.0

.400

44183A

9.4

.370

44125A

13.5

.530

44184A

11.0

.430

44127A

15.7

.620

44185A

13.5

.530

44113A

16.8

.660

44186A

15.0

.600

44129A

24.0

.950

44187A

Key Advantages

Repairs damaged spark plug threads permanently
Stronger than original aluminum threads
No helicoil-style tang to break off
Solid steel construction prevents loosening
Maintains proper spark plug heat range
Professional-grade installation tools included

Common Applications

Stripped spark plug holes
Aluminum cylinder heads
Corroded threads
Thread reinforcement in high performance engines

Professional Tip

For severely damaged threads or failed previous repairs, consider our Big-Sert oversize spark plug repair system. It's designed specifically for cases where standard Time-Sert won't work.

Learn about Big-Sert for Spark Plugs

Ready to Order?

Browse our complete range of spark plug Time-Sert kits in our online store.