Belt Tensioner Pulleys | McMaster-Carr

Filter by

System of Measurement

Shaft Diameter

For Maximum Belt Width

Material

Bearing Type

Width

Diameter

Belt Width

Belt Trade Size

Belt Type

V-Belt Type

Number of Grooves

Idler Type

Toothed

Without Teeth

Number of Teeth

Shaft Mount Type

Bearing Material

Pitch

REACH

DFARS Specialty Metals

Exempt

Export Control Classification Number (ECCN)

RoHS

Tooth Profile

Groove Depth

Bearing Seal Type

90 Products

Flat Belt Idler Pulleys

Nylon

Cast Iron

Steel

Image of Attribute. Front orientation. Contains Annotated.

These pulleys spin freely on built-in bearings to maintain tension for reduced wear and vibration. They’re often used with belt tensioners (sold separately).

Ball Bearing—Pulleys with ball bearings ensure proper positioning inside a tube or housing. They’re sealed to block out dust and contaminants better than pulleys with needle roller bearings.

Needle Roller Bearing—Pulleys with needle roller bearings minimize internal friction.

Nylon—Nylon pulleys are lightweight and corrosion resistant.

Cast Iron and Steel—Cast iron and steel pulleys are more durable than nylon pulleys.

	OD	For Shaft Dia.	Dia.	Wd.	Groove Dp.	Material		Each
Ball Bearing



	5/8"	3.5"	3/8"	3"	1 3/32"	0.25"	Nylon	0000000	000000


	5/8"	3.5"	1/2"	3"	1 3/32"	0.25"	Nylon	0000000	00000
	11/16"	2.5"	0.635"	2 1/4"	7/8"	0.125"	Cast Iron	0000000	00000
	13/16"	2.8"	3/8"	2 33/64"	1 7/32"	0.11"	Nylon	0000000	00000
	13/16"	2.8"	1/2"	2 33/64"	1 7/32"	0.11"	Nylon	0000000	00000
	13/16"	3.5"	3/8"	3"	1 7/32"	0.25"	Nylon	0000000	00000
	13/16"	3.5"	1/2"	3"	1 7/32"	0.25"	Nylon	0000000	00000
	7/8"	2.4"	3/8"	2"	1 5/32"	0.18"	Nylon	0000000	00000
	7/8"	2.4"	1/2"	2"	1 5/32"	0.18"	Nylon	0000000	00000
	7/8"	3"	3/8"	2 1/2"	1 5/16"	0.25"	Nylon	0000000	00000
	7/8"	3"	1/2"	2 1/2"	1 5/16"	0.25"	Nylon	0000000	00000


	7/8"	5.6"	3/8"	5 1/32"	1 19/64"	0.26"	Nylon	0000000	00000
	7/8"	5.6"	1/2"	5 1/32"	1 19/64"	0.26"	Nylon	0000000	00000
	29/32"	4.5"	3/8"	4"	1 25/64"	0.25"	Nylon	0000000	00000
	29/32"	4.5"	1/2"	4"	1 25/64"	0.25"	Nylon	0000000	00000
	1 1/16"	4.5"	0.635"	4"	1 7/16"	0.25"	Cast Iron	0000000	000000
	1 1/8"	2.1"	3/8"	1 7/8"	1 35/64"	0.09"	Nylon	0000000	00000
	1 1/8"	2.1"	1/2"	1 7/8"	1 35/64"	0.09"	Nylon	0000000	00000
	1 1/8"	3.4"	3/8"	2 31/32"	1 43/64"	0.2"	Nylon	0000000	00000
	1 1/8"	3.4"	1/2"	2 31/32"	1 43/64"	0.2"	Nylon	0000000	00000
	2 1/16"	4.5"	0.635"	4"	2 7/16"	0.25"	Cast Iron	0000000	000000


	3 1/16"	4.5"	0.635"	4"	3 7/16"	0.25"	Cast Iron	0000000	000000
	4 1/2"	7"	1"	6"	5"	0.5"	Cast Iron	0000000	000000
	6 1/4"	7"	1"	6"	6 3/4"	0.5"	Cast Iron	0000000	000000


	Needle Roller Bearing



			7/16"	1.4"	1/2"	1 1/8"	5/8"	0.125"	Steel	000000	00000


			9/16"	1.8"	1/2"	1 3/8"	13/16"	0.187"	Steel	000000	00000
			11/16"	2.5"	1"	2 1/4"	7/8"	0.125"	Steel	000000	00000
			1 1/16"	4.5"	1"	4"	1 7/16"	0.25"	Cast Iron	000000	000000
			2 1/16"	4.5"	1"	4"	2 7/16"	0.25"	Cast Iron	000000	000000
			3 1/16"	4.5"	1"	4"	3 7/16"	0.25"	Cast Iron	000000	000000
			4 1/2"	7"	1 1/2"	6"	5"	0.5"	Cast Iron	0000000	000000

GT Timing Belt Idler Pulleys

Toothed

Without Teeth

Get pitch-perfect compatibility with these free-spinning pulleys. They mesh with belts that have curved GT-profile teeth, reducing vibration and wear. As they rotate on their bearings, these pulleys press up against belts to reduce slack and keep the system moving smoothly. All are compatible with GatesPowerGrip GT, 2GT, GT2, GT3, and GT4 series. Idler pulleys are often used with belt tensioners.

Iron—Strong, but best for dry environments since moisture will cause them to rust.

Corrosion-Resistant Aluminum—Lightweight and resist rust in wet environments. Although aluminum pulleys are one-third the weight of iron pulleys, they aren't as strong.

Without Teeth—These pulleys press against the smooth side of the belt instead of the toothed side to maintain tension.

						Toothed			Without Teeth
	For Max. Belt Wd., mm	Pitch, mm	For Shaft Dia., mm	OD, mm	Bearing Type	No. of Teeth		Each		Each
For 2MGT Trade Size







				Corrosion-Resistant Aluminum

				6	2	3	15	Ball	20	00000000	00000	00000000	00000


				6	2	5	15	Ball	20	0000000	0000	0000000	0000
				9	2	3	15	Ball	20	00000000	0000	00000000	0000
				9	2	5	15	Ball	20	0000000	0000	0000000	0000
				12	2	3	15	Ball	20	00000000	0000	00000000	0000
				12	2	5	15	Ball	20	0000000	0000	0000000	0000


				For 8MGT Trade Size







								Iron

								20	8	20	90	Roller	32	0000000	000000	———	0


								30	8	30	100	Roller	36	0000000	000000	———	0
								62	8	30	100	Roller	36	0000000	000000	———	0


								For 14MGT Trade Size







												Iron

												37	14	40	146	Roller	30	0000000	000000	———	0

Round Belt Idler Pulleys


Brass	Nylon

These pulleys spin freely on built-in bearings to maintain tension for reduced wear and vibration. They are often used with belt tensioners (sold separately). Ball bearings are double sealed to keep dirt out.

Brass—Brass pulleys are nonsparking and fit in extremely small spaces.

Nylon—Nylon pulleys are lightweight and corrosion and abrasion resistant.

For Belt Dia.	OD	For Shaft Dia.	Dia.	Wd.	Groove Dp.	Material	Bearing Material		Each
3/32"	0.8"	1/8"	0.654"	9/64"	0.048"	Brass	Stainless Steel	000000	000000
3/32"	1"	1/8"	0.904"	5/32"	0.048"	Brass	Stainless Steel	000000	00000
3/32"	1.5"	1/8"	1.404"	5/32"	0.048"	Brass	Stainless Steel	000000	00000
1/8"	1"	1/4"	0.872"	3/16"	0.064"	Brass	Stainless Steel	000000	00000
1/8"	1.5"	1/4"	1.372"	3/16"	0.064"	Brass	Stainless Steel	000000	00000
1/8"	1.5"	1/4"	1.372"	13/64"	0.064"	Brass	Stainless Steel	000000	00000
1/8"	2"	1/4"	1.872"	13/64"	0.064"	Brass	Stainless Steel	000000	00000
3/16"	2"	3/8"	1.81"	9/32"	0.095"	Brass	Stainless Steel	000000	00000
3/16"	2.5"	3/8"	2.31"	9/32"	0.095"	Brass	Stainless Steel	0000000	00000
1/4"	4.5"	3/8"	3.74"	55/64"	0.36"	Nylon	Steel	00000000	00000
1/4"	4.5"	1/2"	3.74"	55/64"	0.36"	Nylon	Steel	00000000	00000
1/4"	6"	3/8"	5.2"	51/64"	0.4"	Nylon	Steel	00000000	00000
1/4"	6"	1/2"	5.2"	51/64"	0.4"	Nylon	Steel	00000000	00000
3/8"	3.1"	3/8"	2.45"	39/64"	0.3"	Nylon	Steel	00000000	00000
3/8"	3.1"	1/2"	2.45"	39/64"	0.3"	Nylon	Steel	00000000	00000
3/8"	3.5"	3/8"	2.75"	49/64"	3/8"	Nylon	Steel	00000000	00000
3/8"	3.5"	1/2"	2.75"	49/64"	3/8"	Nylon	Steel	00000000	00000
3/8"	5.5"	3/8"	4.62"	9/16"	0.44"	Nylon	Steel	00000000	00000
3/8"	5.5"	1/2"	4.62"	9/16"	0.44"	Nylon	Steel	00000000	00000
11/16"	4.8"	3/8"	4"	1 1/16"	0.41"	Nylon	Steel	00000000	00000
11/16"	4.8"	1/2"	4"	1 1/16"	0.41"	Nylon	Steel	00000000	00000

V-Belt Idler Pulleys


1 Groove	2 Grooves	3 Grooves

These idler pulleys spin freely on built-in ball bearings to maintain tension for reduced wear and vibration. Commonly used with belt tensioners (sold separately), they are lightweight and corrosion and abrasion resistant. Bearings are double sealed to keep dirt out.

	OD	For Shaft Dia.	Pitch Dia.	Wd.	Groove Dp.	Material	Body Type		Each
For 4L, A, AX Belts



	1	3"	3/8"	2"	45/64"	0.5"	Nylon	Solid	0000000	000000


	1	3"	1/2"	2"	45/64"	0.5"	Nylon	Solid	0000000	00000
	1	4"	3/8"	2.99"	45/64"	0.5"	Nylon	Solid	0000000	00000
	1	4"	1/2"	2.99"	45/64"	0.5"	Nylon	Solid	0000000	00000
	1	6"	1/2"	5.12"	23/32"	0.46"	Nylon	Solid	0000000	00000
	1	7.5"	1/2"	6.6"	23/32"	0.45"	Nylon	Solid	0000000	00000


	For 5L, B, BX Belts



			1	3.1"	3/8"	1.84"	25/32"	0.63"	Nylon	Solid	0000000	00000


			1	3.1"	1/2"	1.84"	25/32"	0.63"	Nylon	Solid	0000000	00000
			1	4"	3/8"	2.84"	55/64"	0.58"	Nylon	Solid	0000000	00000
			1	4"	1/2"	2.84"	55/64"	0.58"	Nylon	Solid	0000000	00000
			1	5"	3/8"	3.84"	51/64"	0.6"	Nylon	Solid	0000000	00000
			1	5"	1/2"	3.84"	51/64"	0.6"	Nylon	Solid	0000000	00000
			2	6.3"	1/2"	5.18"	1 23/32"	0.55"	Nylon	Solid	00000000	000000
			3	6.3"	1/2"	5.18"	2 7/16"	0.55"	Nylon	Solid	00000000	000000

Timing Belt Idler Pulleys

Reduce vibration and wear on your timing belt with idler pulleys that maintain constant tension. Their trapezoidal teeth mesh with matching grooves on your timing belt, pressing against the belt to take up slack. Plus, they rotate freely on bearings to keep the belt moving smoothly. Idler pulleys are often used with belt tensioners.

Steel and Iron—Strong, but best for dry environments since moisture will cause them to rust.

	For Shaft Dia.	OD	Bearing Type		Each
For XL Trade Size







	Steel

	1/2"	24	0.2"	1/2"	1 1/2"	Roller	0000000	000000


	3/4"	22	0.2"	1/2"	1 3/8"	Roller	0000000	00000


	For L Trade Size







					Steel

					1"	18	0.375"	1"	2 1/8"	Roller	0000000	00000


					1"	22	0.375"	1"	2 5/8"	Roller	0000000	00000


					For H Trade Size







									Steel

									1"	16	0.5"	1"	2 1/2"	Roller	0000000	00000


									2"	16	0.5"	1"	2 1/2"	Roller	0000000	00000




											Iron

											3"	18	0.5"	1"	2 13/16"	Roller	0000000	000000

HTD Timing Belt Idler Pulleys

Keep HTD timing belt systems running tightly with these idler pulleys. Curved teeth press against the belt as bearings rotate freely, reducing vibration and wear. All are compatible with Gates PowerGrip HTD, Omega HP, and Carlisle RPP series. Idler pulleys are often used with belt tensioners.

Iron—Strong, but best for dry environments since moisture will cause them to rust.

	For Shaft Dia.	OD	Bearing Type		Each
For H8M Trade Size







	Iron

	30	19	8	1"	1 7/8"	Roller	0000000	000000