WHAT IS A TIMING BELT?

A timing belt, also known as a Cambelt, Engine belt, is a crucial component of an internal combustion engine. It is a toothed belt that is responsible for synchronizing the rotation of the engine’s crankshaft and camshaft(s). It ensures that the valves open and close at the correct time in relation to the movement of the pistons.

One of the main reasons why a timing belt is so important is that it controls the precise timing of the engine’s valves. If the timing belt were to break or slip, the valves and pistons could collide, causing potentially catastrophic damage to the engine. This is why it is essential to replace the timing belt at regular intervals as recommended by the manufacturer

Timing Belt Structure:

The construction of timing belts involves several key components that work together to ensure precise and reliable performance. It is typically made of rubber and reinforced with nylon cords or other materials to provide strength and durability. It is designed to withstand high temperatures and pressures, as well as the continuous movement and vibration of the engine. The teeth on the belt mesh with the gears on the crankshaft and camshaft(s), ensuring that they rotate in perfect harmony.

1. Belt body - high quality synthetic HNBR or CR rubber

HNBR (Hydrogenated Nitrile Butadiene Rubber) and CR (Chloroprene Rubber) are commonly used materials for the body of timing belts due to their excellent mechanical properties and resistance to heat, oil, and abrasion.
These rubber materials provide flexibility, durability, and resistance to wear and tear. The timing belt needs to withstand high tensions and harsh operating conditions while maintaining precise synchronization between engine components.
The properties of HNBR and CR rubber help the timing belt maintain its shape and integrity under stress, allowing it to operate smoothly and reliably over an extended period. Additionally, the rubber material also helps dampen vibrations and reduce noise during operation, contributing to the overall efficiency and performance of the timing belt system.

2. Tensile Cord: excellent quality fiberglass cord with high tensile strength and elasticity

The fiberglass cord providing structural support and reinforcement to the timing belt. The high tensile strength and elasticity of the fiberglass cord enhances the overall durability, stability, and performance of the timing belt by improving its resistance to stretching, breaking, and deformation under heavy loads.
It ensures that the timing belt maintains precise synchronization between engine components and operates smoothly and efficiently over a prolonged period.

3. Belt teeth - Protected by highly wear resistant nylon elastic fabric

The nylon elastic fabric serves as a protective layer for the teeth of the timing belt. The function of the nylon elastic fabric in the timing belt teeth is to enhance wear resistance and reduce friction during operation.
Additionally, the nylon elastic fabric has a low skin-friction coefficient, which means it helps reduce friction between the teeth of the belt and the pulleys, allowing for smooth and efficient power transmission. This feature helps minimize energy losses and heat generation, improving the overall performance and longevity of the timing belt.

How to recognize timing belt reference number

The reference number “111MR17” typically consists of three important pieces of information regarding the timing belt size and specifications:

— “111” – This indicates the number of teeth on the timing belt. In this case, the belt has 111 teeth.

— “MR” – This indicates the teeth shape and pitch of the timing belt. The “MR” designation usually refers to a metric pitch.

— “17” – This refers to the belt width in millimeters. In this case, the belt has a width of 17mm.

Timing belt tooth profile comparison table with other well-known brands

Crossing #	Gates #	Contitech #	Tooth H/ mm	Pitch L/ mm
MR	58XXX	HTD	3.54	9.525
MY	39XXX	HTDK8M	3.06	8
RU	76XXX	HTDA	3.44	9.525
YU	77XXX	HTDA8M	3.11	8
ZA	41XXX	LA	1.91	9.525
ZB	45XXX	LAH	2.29	9.525
ZBS	63XXX	LAHR	2.76	9.525
S8M	90XXX	STD	3.05	8

Crossing company part of Timing Belt list

100MR170	117RU220	130STDN8M150	149MR254	197YU26
117RU22	130S8M200	149MR25	197YU20	99ZB19
117MY210	130S8M20	148ZA190	197RU24	99YU190
117MY21	130R25	148ZA19	196RU280	99RU25
117MR190	130MR250	148S8M250A	196RU28	99MY160
116ZA190	130MR25	148S8M230	195YU320	98ZB190
116ZA19	130CHDN25.4	148S8M23	195YU32	98ZA190
116YU290	129YU180	148RU254	195CPPN29	98ZA17
116YU29	129RU254	148RU230	193YU32	97ZB15
116X220	129RU250	148MR250	193STDN8M240	97ZA254
116RU250	129RU25.4	147S8M250	193S8M360	97ZA19
116MR190	129RU25	147S8M190	193S8M36	97RU25
116CHD25.4	129MY270	147S8M19	192S8M300	97RU22
115ZA200	129MR310	147MR240	192S8M30	97RU21.6
115S8M25	129MR31	146ZA190	192RU280	97RU19
115MR190	129MR240	146ZA19	191S8M320	97MR25
114RU17	129MR24	146YU190A	191S8M32	97MR218
114MR250	129CPPN22	146S8M240	191S8M31.8	97MR198
114MR25	128YU26	146S8M24	191MY360	96ZB25
114MR170	128S8M250	146S8M200	191MY36	96X19
114MR17	128S8M190	146S8M20	187YU320	96MR17.3
113ZA190	128RU270	146RU280	187YU32	96MR17
113RU254	128MY27	146RU28	185MR280	95ZA190
113RU25.4	128MY260	146MY254	179YU20	95ZA19
113RU25	128MY26	146MY25	179S8M320	95RU25
113RU240	127ZA250A	146MR240	179S8M32	95RU234
113RU24	127ZA25	145ZA180	178MY254	95RU19
113RU17	127RU250B	145ZA18	178MY25	95MR170
113MR190	127RU25.4	145YU260	178MR250	94ZA19
113MR19	127RU25	145YU220	178MR25	94MR25
113MR170	127RU240	145YU22	178CPPN30	93ZA190
112ZA190	127RU24	145S8M230	177YU30	93RU25
112ZA18	127MY24	145RU300	177RU25	92ZBS19
112RU290	127MR250	145MY216	177MY250	92ZA19
112RU29	127MR25.4	144ZA190	177MY25	92RU22
112RU240	127MR25	144ZA19	177MR254	92MR25
112RU24	127MR190	144RU230	177MR25.4	92MR197
112MR190	127HTB25.4	144MR254	177MR25	91ZA190
111ZA25.4	126ZA254	144MR25.4	176S8M240	91RU19
111ZA25	126ZA25	143ZB300	176RU280	91RU075
111ZA190	126ZA23.8	143ZA254	176RU28	91CHDN20
111YU290	126YU230	143ZA25	175S8M290	90ZA19
111YU29	126STDN8M150	143ZA190	175S8M29	89ZA190
111SP17	126RU270	143ZA19	174MR280	89ZA19
111RU254	126RU27	143YU260	173YU25.4	89RU254
111RU25.4	126RU26	143YU230	173YU25,4	89RU25
111RU25	126RU24	143RU250	173YU25	89RU190A
111RU17	125YU220	143RU210	173STDN8M250	88ZA190
111RPP19	125YU22	143MY25	173STDN8M220	88ZA19
111MY250	125RU260	143MR254A	173S8M300	87ZB340
111MR170	125RU26	142ZA250	173S8M30	87ZA19
111MR17	125MR200	142ZA25	173S8M30	87MR170
111HTDN19	125MR20	142ZA180	173S8M290	84ZA190
110ZA254	125MR190	142ZA18	173S8M29	83ZBS190
110ZA25.4	125MR19	142S8M190	171S8M240	83ZBS19
110ZA180	124ZA24.7	142RU230	171S8M24	83RU300
110ZA18	124RU290	142RU23	170STDN8M250	83RU240
110YU190	124RU29	141ZBS300	170STDN8M220	83RU24
110S8M220	124RU260	141ZBS250	169S8M240	83RU190A
110S8M22	124RU26	141ZA254	169S8M24	83RU19
110RU250	124RU240	141ZA25	169S8M200	81ZBS210
110RU25	124RU24	141RU300	169S8M20	81ZBS21
110MR210	124MY260	141RU30	169MY254	80ZA25.4
110MR21	124MY26	141MR280	169MY25	80LAHN210
110MR20.7	124MR190	139ZA254	168YU250	79RU190
110MR180A	124LAN180	139ZA25	168YU25.4	78MR190
110MR170	124LAN18	139ZA180	168YU25	77LAHN210
110DHTD140	124HTB29	139ZA18	168S8M240	77LAHN21
109ZA190	124HTB22	139RU210	167YU25.4	76ZBS190
109YU250	123ZBS190B	138ZA254	167YU25,4	75ZB200
109YU25	123ZBS190	138ZA25	167STDN8M240	71MR178
109YU160	123ZBS19	138ZA180	166STDN8M240	70ZA15.9
109MY250	123ZB254	138ZA18	164S8M250	70RU160
109MR220	123ZB25.4	138S8M230	164S8M25	70RU16
109MR190	123ZA190	138S8M23	163ZBS250	69ZA190
108ZA190	123ZA19	138RU230	163ZBS25.4	69YU150
108ZA19	123YU220	138MR285	163ZBS25	69YU15
108RU318	123YU22	138MR28.5	163S8M270	68ZA150
108RU250	123RU290	137ZBS250B	163S8M27	68ZA15
108RU25	123RU29	137ZBS250	163S8M26.7	68YU230
108RU100	123RU280	137ZBS25	163RU254	65YU13
108MR240	123RU28	137ZBS230	163RU25	65YU127
108MR170	123RU270	137ZB300	162S8M300	65YU12.7
108MR17	123RU27	137YU19	162S8M250	65YU12
108LAN150	123RU190A	137STP8M22	162S8M25	65S8M13
108HTB25.4	123RU190	137S8M250	162S8M200	65S8M127
107YU254	123MY240	137S8M25	162S8M20	65S8M12
107YU25.4	123MY24	137S8M220	160RU30	63ZA190
107YU25	123MY200	137S8M22	160RU25	62ZB190
107YU220	123MY20	137S8M190	159YU29	59RU220
107YU22	123HTB29	137S8M19	159MY254	59RU22
107YU190	122ZBS265	137RU22	159MY25	58S8M170
107YU180	122ZBS26.5	137MY25	158STDN8M254	58S8M17
107YU160	122ZBS190	137CPPN25	158RU320	57ZA190
107Y21	122ZBS19	136ZB250	157RU254	57ZA19
107RU240	122RU290	136SP25.4	157MR320	55ZBS13
107RU24	122RU29	136RPP25.4	157MR230	55ZBS127
107MY220	122RU240	136MR254	156YU290	55ZBS12
107MY21.6	122RU24	136MR250	155YU240	55ZA127
107MY190	122RU200	136MR25	155YU24	54ZA190
107MR240	122RU20	136CPPN25	155YU190	54ZA19
107MR200	122RU190	135YU254	154YU290	54MR170
106ZA190	122RU19	135YU250	154YU220	46ZA190
106ZA19	122LAR19	135YU25	154YU22	45ZA100
106RU240	121ZA180	135YU100	154RU290	299S8M300
106RU24	121ZA18	135S8M190	154RU25.4	281YU300
106MR24	121YU290	135RU250	153ZB300	281YU30
106MR220	121YU29	135RU25.4	153ZB30	281S8M300
106MR190	121MY240	135LANH25.4	153ZB250	265YU320
105ZA190	121MY24	134ZA254	153S8M250	265YU32
105RU220	121MY210	134ZA25	153S8M25	259YU32
105RU22	121MY21	134STDN8M180	153RU300	259STDN8M320
105MR25	121MY200	134SP25.4	153RU290	257YU320
104ZA170	121MY20	134RU270	153RU29	257YU32
104ZA150	121MR200	134RU250	153RU270	253S8M300
104ZA15	121MR20	134RU25.4	153RU260	253S8M30
104YU160	121LAN18	134MR254A	153RU250	251YU320
104SP17	120ZBS190	134MR250	153RU25.4	239S8M254
104RU254	120ZA190	134MR25	153RU25	239S8M25.4
104RU240	120ZA180	133ZA250	153MR254	228YU32
104RU24	120ZA18	133ZA25	152ZB300	226YU300
104RU220	120ZA150	133ZA220	152ZB30	225S8M300
104RU22	120ZA15	133ZA22	152S8M250	223YU270
104RU17	120RU300	133ZA190	152S8M25	223YU27
104MR170	120RU30	133ZA19	152RU300	223YU26
104MR17	120LAHN254	133YU250	152RU30	223S8M320
104LA15	11X528	133YU25	152RU280	223S8M32
103ZA190	119ZB320	133S8M190	151S8M250	223MY27
103RU26.5	119ZB250	133RU260	151S8M190	220S8M280
103RU25	119ZA19	133RU25	151RU300	220S8M220
103RU240	119SX190	133MR254	151RU30	219ZB254
103RU24	119RU32	133MR240	151RU29	219MY32
103RU220	119RU250	132S8M190	151RU254A	219MR254
103RU190A	119RU190	132RU280	151MR254	218S8M32
103MY190	118ZB320	132RU28	150S8M230	211YU300
103MY16	118ZA25	132RU274	150S8M23	211YU30
102ZA205	118ZA19	132RU27	150RU290	211S8M34
102ZA190	118ZA150	132RU260	150RU29	211MY320
102RU190	118ZA15	132MR230	150MR25.4	211MY32
102R25	118RU25.4	132HTDD27.4	150MR25	209S8M34
102MR25	118MR190	131STDN8M170	149ZBS300A	207YU320
101YU200	117ZB25.4	131RU27	149ZB300	207YU32
101YU20	117ZA150	131RU254	149ZB30	202YU30
101RU300	117ZA15	131RU250	149S8M250	201YU32
101MR240	117YU290	131RU25	149RU300B	201YU300
101MR170	117YU29	131RU22.3	149RU254	201YU30
100ZA170	117RU300	130ZB254	149RU25	200YU30
100MY190	117RU254	130ZB25.4	149RU240	197YU260

How Long A Timing Belt Lasts?

The longevity of a timing belt ultimately depends on several factors including the material it is made of, the quality of installation, and the driving conditions it is subjected to. On average, timing belts are designed to last between 50,000 to 100,000 kilo meters. However, some manufacturers recommend replacing the timing belt every 2 years or 50,000 kilo meters, whichever comes first.

As a preventative measure to avoid potential engine damage. It is important to follow the manufacturer’s recommendations for timing belt replacement to prevent costly repairs and ensure the continued smooth operation of the engine. Regular inspection of the timing belt for signs of wear and tear, such as cracking or fraying, is also essential in maintaining the integrity of the engine. It is recommended to consult with a certified mechanic for proper maintenance and replacement of the timing belt to ensure optimal performance and longevity of the engine.