Ensemble de boîtier arrière FAW: Une analyse experte de 22 Composants de base

Bienvenue dans cette analyse experte du Ensemble de boîtier arrière FAW (Partie no. 1701505-A9P), la critique “boîte auxiliaire” ou “range box” for the manual transmission in the FAW Jiefang CA4251P66K24T1A3E5 6×4 tracteur semi-remorque diesel.

Ce Ensemble de boîtier arrière FAW is the foundation of the transmission’s “diviseur” ou “gamme” section. It bolts to the back of the main transmission case and contains the crucial gearset that provides the “haut” et “faible” ranges, effectively doubling the number of available gears (Par exemple, turning a 6-speed into a 12-speed).

Ce guide détaillé est une ressource essentielle pour les techniciens professionnels de transmission et les spécialistes des pièces.. Nous déconstruirons l'ensemble Ensemble de boîtier arrière FAW dans son 22 composants réparables, y compris le logement principal, the output shaft bearings, the critical adjustment shims, and the speedometer drive system.

Composant principal: The Rear Housing Assembly (1701505-A9P)

The foundation of this entire assembly is the ‘Rear housing with steel wire sleeve set assy’ (1701505-A9P). This is the main structural casing of the Ensemble de boîtier arrière FAW (boîte auxiliaire). C'est un énorme, precision-machined casting, typically made of aluminum to save weight and dissipate heat.

Its function is to house the entire “gamme” gearset, which includes the range synchronizer and the “haut” et “faible” ratio gears. It must hold the auxiliary output shaft and auxiliary counter-shaft in perfect, parallel alignment under thousands of pound-feet of multiplied torque.

Le “steel wire sleeve set” designation is a critical, high-quality feature. It means that the high-stress threaded holes in the aluminum Ensemble de boîtier arrière FAW are pre-fitted with “Helicoils” (steel wire thread inserts). This prevents technicians from stripping the soft aluminum threads when tightening the heavy-duty steel bolts, dramatically increasing the component’s service life and durability.

The Critical “Calage” Système: Adjustment Gaskets

The most complex and “logical” une partie du Ensemble de boîtier arrière FAW is its shimming system. The parts list details ten different ‘Adjustment gasket-sub box intermediate shaft’ composants (Numéros de pièces. 1701526-A9P through 1701537-A9P). These are not standard gaskets; they are **selective shims**.

When a transmission is built, le “fin de jeu” (the amount of fore-and-aft movement) of the counter-shaft is a critical, zero-tolerance specification. If the shaft is too “lâche,” the helical gears will “gémissement” and fail to mesh properly. If it is too “serré,” the bearings will overheat, saisir, and be destroyed.

La remarque “(See 1701526-A9P)” indicates that these parts form a set. A technician assembles the Ensemble de boîtier arrière FAW, measures the end-play with a dial indicator, and then consults a service manual. The manual will instruct them to select *one specific shim* (Par exemple, 1701528-A9P) from this set. Each shim has a minutely different thickness.

Installing this one, correct shim sets the bearing “précharger” aux spécifications d'usine parfaites. This shimming procedure is the single most important step in rebuilding a Ensemble de boîtier arrière FAW, as it ensures a quiet, fiable, and long-lasting gearbox.

The Output System: Roulements, Caps, et compteur de vitesse

Le Ensemble de boîtier arrière FAW provides the final output to the vehicle’s driveshaft. This is supported by the ‘Rear bearing-sub box output shaft’ (1701586-A9P). This is a massive roller bearing that supports the final output shaft, which is subjected to the full, multiplied torque of the selected gear ratio.

This bearing is held in place by the ‘Rear bearing cap-sub box output shaft’ (1701521-A9P), which is a heavy-duty cap that bolts to the rear of the Ensemble de boîtier arrière FAW. This cap not only retains the bearing but also houses the main output shaft oil seal (pas de photo), which prevents all the gear oil from leaking out.

This sub-assembly also contains the ‘Speedometer driven shaft assembly’ (1701440-11) and its corresponding ‘Driven gear-speedometer’ (1701446-A9P). This is the mechanical “prise de force” for the speedometer. A plastic gear on the output shaft spins this driven gear, which in turn spins a cable or electronic sensor (via the ‘Speedometer connector’ 1701447-A9P) to provide the vehicle speed to the dashboard. This is a critical data-reporting function of the Ensemble de boîtier arrière FAW.

Service, Soutien, et attaches

Le Ensemble de boîtier arrière FAW is designed for service. It includes an ‘Oil filler plug assembly’ (1701765-A2K) et son 'Joint’ (1701042-A2K) for filling the auxiliary box with its own separate oil supply. It also features a ‘Cover-sub box shifting oil hole’ (1701517-A9P) for accessing and servicing the range-shifter mechanism.

L'ensemble Ensemble de boîtier arrière FAW is supported and held rigid by the ‘Tension rod flexible cushion assembly’ (1302050-01) and its associated ‘Cushion’ (1302052-01). Ces “stay rods” connect the heavy transmission to the chassis crossmembers, preventing the entire powertrain from twisting under torque and allowing the ‘Tension bolt’ (1702129-1H) to maintain perfect alignment.

The assembly is held together with a massive number of high-tensile fasteners, y compris les « boulons à bride hexagonale’ (Q1841035S, Q1841085S, Q1841035S) et « Boulons à tête hexagonale’ (CQ1500512S). The ‘Spring gaskets’ (Q40308, Q40405) et « Écrous hexagonaux’ (CQ34008) are critical for ensuring none of these fasteners vibrate loose, which would be catastrophic for the Ensemble de boîtier arrière FAW.

FAW Rear Housing Assembly Parts List

Le tableau suivant fournit l'intégralité, ventilation détaillée de tous 22 components identified in the ‘Rear Housing Assembly’ (Sub-Box) schéma du tracteur FAW CA4251P66K24T1A3E5. Une reconstruction du Ensemble de boîtier arrière FAW requires careful selection of the correct adjustment gaskets.

Spécifications techniques et contexte d'assemblage

Les spécifications pour le Ensemble de boîtier arrière FAW are defined by its function as the structural, precision-machined “sous-boîte” ou “range box”. L'ensemble Ensemble de boîtier arrière FAW is a zero-tolerance component.