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This page explains which engine pulleys were used as well as the belt routing for the 71 429 Mustang and Cougar.  

(Note: Click thumbnails to enlarge pictures.)

429 CJ/SCJ Belt Routing Diagrams
feadcjac.jpg (43518 bytes)

429CJfead.jpg (89664 bytes)

429 CJ with A/C

feadCJwoAC.jpg (33543 bytes)

accessorydrive.jpg (93132 bytes)

429 CJ without A/C

feadSCJ.jpg (37455 bytes)

429 SCJ (note: P/S or idler not present in this photo)


Water Pump Pulleys

Three different WP Pulleys were used on the 429 CJ/SCJ Mustang and 2 different WP pulleys on the 429 CJ Cougar.

    wpsinglegroove4.jpg (68717 bytes)     WP8.jpg (63814 bytes)     WPpulleySingleGroove2a.jpg (11217 bytes)

This is the single groove water pump pulley for the CJ without A/C (Part # D0SE-8509-A) and is 6 1/2" in diameter.

   WPpulleyCJwAC8.jpg (88192 bytes)     WPpulleyCJwAC7.jpg (64740 bytes)     WPpulleywAC9.jpg (16188 bytes)

This is the 2 groove water pump pulley used on the CJ with A/C (Part #D0OE-8509-L). Note the larger diameter outer groove for A/C. The belt that goes in the outer groove lines up with the outer groove on the 3 groove crank pulley, the A/C Pulley, Fixed A/C Idler, and Adjustable A/C Idler.  The inner groove is used by the belt that goes on the middle crank pulley groove and the P/S Pulley (or idler on a non-P/S car).  

WPpulleySCJ3a.jpg (34554 bytes)    WPpulleySCJ1a.jpg (23177 bytes)    WPpulleySCJ2a.jpg (24238 bytes)        wpscjinstall.jpg (148108 bytes)

The SCJ also uses a 2 groove pulley (Part #D0OE- 8509-M), but the outer groove (5 3/4" dia.), which drives the Smog Pump, has a smaller diameter than the inner groove (6 1/2" dia.). Also, the outer groove has a narrower "V" groove for the narrower width v-belt used on the D0SE smog pump pulley. The inner groove is used by the belt that goes on the inner crank pulley groove (of the 2 groove crank pulley) and the P/S Pulley (or idler on a non-P/S car). 


Non Power Steering Idler

You might wonder why it is necessary to put an Idler on in place of the Power Steering (PS) Pump on the Non PS cars? The answer is to provide a tensioning method for the belt that drives the water pump! The water pump is driven by a belt that wraps the Crank Pulley, Water Pump (WP) Pulley and PS Pump Pulley. Belt tension was adjusted via the PS bracket on PS equipped cars (see this photo psadjust.jpg (80181 bytes) ). Without an adjuster of some type at the PS position, there would be no way to tension the belt between the WP and Crank Pulley. The Non Power Steering Idler, like the PS bracket, is also adjustable (as shown in this photo psidlertension.jpg (53025 bytes) ) and is used to set belt tension. The pulley assembly part number is stamped number DOAE-8A617-B2 (service numbers D0AZ-8679-A or Motorcraft # YS-32) and the bracket stamped part number is DOAE-8A620-A (service numbers D0AZ-8680-A or Motorcraft # YS-43).

              PSidler2.jpg (34858 bytes)

Installed views of P/S Idler

      psidler8a.jpg (43330 bytes)     Idler.jpg (27475 bytes)        

         psidler7.jpg (48733 bytes)       psidler8.jpg (37351 bytes)

Various Views

PSidlerc.jpg (141039 bytes)

Main support bracket

PSidlera.jpg (144489 bytes)


PSidlerb.jpg (74870 bytes)

Idler Bracket

PSidlerd.jpg (76779 bytes)

Assembled views

PSidlere.jpg (96299 bytes) PSidlerF.jpg (144345 bytes)

Spacer used with this assembly.


A/C Idler 

Two A/C Idlers were used together on the 429 CJ with Air Conditioning. An Adjustable Idler up next to the A/C compressor and a Fixed Idler that bolted to the P/S Bracket and Water Pump.

A/C Idler - Adjustable

adjIdler5.jpg (36807 bytes)   adjIdler6.jpg (37796 bytes)   adjIdler7.jpg (38582 bytes)

This is the Adjustable A/C Idler. It was used to adjust belt tension on the A/C compressor. A square slot was  placed in the bracket to allow a breaker bar to be inserted and levered by the mechanic to set belt tension. The factory part number from the MPC for this part is D0AZ-8678-C, however no stamped part number is visible on parts we have examined. Installed views of the Adjustable A/C Idler are shown below.

AdjustableACidler4.jpg (31967 bytes)   acidler6.jpg (132504 bytes)   acidler7.jpg (113804 bytes)

A/C Idler - Fixed

  fixedidler6.jpg (37662 bytes)  fixedidler7.jpg (38538 bytes)   fixedidler8.jpg (36917 bytes)

This is the Fixed A/C Idler that bolted to the Water pump and P/S bracket. We suspect this fixed idler was used to keep the belt from vibrating on the long span from the A/C Compressor to the Crank Pulley. The factory part number for this part is D0AZ- 8678-B, however, the service part seems to be far more common at swap meets. It has part number D3AH-8A617-AA as shown below left. An installed view of the Fixed Idler is shown below right.

fixedIdler5.jpg (36152 bytes)         fixedidler4.jpg (33531 bytes)


Crankshaft Pulleys/Related

Two different Crankshaft Pulleys were used on the 429 CJ and SCJ. The CJ w/o A/C and SCJ used a two groove version while the CJ with A/C used a three groove version.

pulley 429 3 grove back.jpg (92994 bytes)                

This is the 2 groove Crank Pulley (Part #D0OE-6312-F) used on all SCJ and CJ without A/C. 
The inner (rear) groove is 7.0" diameter and the outer (front) groove is 6 1/4" diameter.

crankpulleyAC.jpg (56482 bytes)      crankpulley3groove2.jpg (41474 bytes)

This is the 3 Groove Crank Pulley (Part # D0OE- 6312-J) for use on the CJ with A/C.
Pulley Diameters; rear groove -7 1/16", middle groove 6 1/4", front groove 7 5/32".

       balancer.jpg (45318 bytes)

This is the Crank Dampener/Balancer used on both the 429 CJ and SCJ  (Part #D0OE-6316-B2)
Balancer diameter: 6 21/32".


Alternator Pulley

  d1zfaltpulley1.jpg (122949 bytes)  alternatorpulley.jpg (48686 bytes)  d1zfaltpulley2.jpg (77410 bytes)  d1zfaltpulley3.jpg (65343 bytes)

This is the 3.05" diameter stamped steel alternator pulley (Part #D1ZF-10A352-AA) used on all 429 CJ/SCJ 55 amp alternators.


Powersteering Pulley

 PSpulley3.jpg (73131 bytes)     PSpulley4.jpg (52116 bytes)     PSpulley.jpg (63942 bytes)

This is the P/S Pulley (Part #D0AR-3D673-A) used on the 429 CJ/SCJ. It had a diameter of 5 5/8".


Smog Pulley

  smogPulleyD0SE2.jpg (70428 bytes)  SmogPulleyD0SE3.jpg (34941 bytes)  SmogPulleyD0SE4.jpg (36714 bytes)  p10fredsmog.jpg (45441 bytes)

This is Smog Pump Pulley (Part# D0SE-9C480-A) used on the SCJ Smog Pump. It had a 5 1/2" diameter with a 15/32" sheave. 

Note To Our 429 CJ/SCJ Torino/Cyclone/Ranchero Friends: During the research for this page, it was noted that several of the pulley's listed above for the 71 429 CJ/SCJ Mustang and Cougar had different part numbers/diameters than those listed for your 429 CJ/SCJ Torino/Cyclone/Ranchero applications. Please be aware of this when using this site and we recommend that you reference the MPC for the correct part numbers for your vehicles.                           

429 Group Member Cars at the Mustang 40th Anniversary

Jim Ginger's 429 CJ Mach 1