CAT 9N-5246 67.45mm Outer Diameter Camshaft Bearing

CAT 9N-5246 is a Caterpillar original steel-backed aluminum-based camshaft bearing, suitable for diesel engines such as 3204/3206/3208. It has an outer diameter of 67.45 mm and is used to support the camshaft and reduce friction. There is one piece per cylinder, and there are usually 3-4 pieces on the oil passage side of the whole engine. The weight of each piece is about 0.18 kg. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes Model 9N-5246, Bearing type sliding bearing, outer diameter φ67.45 mm (tolerance +0.02/-0.01 mm), inner diameter φ50.80 mm (tolerance +0.01/-0.02 mm), width 19.05 mm (0.75 in), locating lip height 2.5 mm, operating temperature -30℃ to +150℃, rated surface pressure 18 MPa, coefficient of friction ≤0.12

Key Dimensions Bearing thickness 3.325 mm (steel back 1.2 mm + aluminum base alloy layer 2.125 mm), 3 oil grooves (circumferentially distributed, width 2 mm, depth 0.5 mm), oil hole diameter φ3 mm (1, located at the bottom of the main oil groove), chamfer C0.5 mm at both ends

Material and Process Steel back (low carbon steel, HB) 180-200) + High-tin aluminum-based alloy (AlSn20Cu, containing 20% ​​tin and 1% copper, hardness HB 35-45), surface plated with a 0.005 mm tin layer for corrosion protection, no solid lubricant coating, relies on pressure lubrication, surface roughness Ra≤0.4 μm
Compatible Models: Compatible with Cat 3204, 3206, and 3208 diesel engines, as well as 215 excavators, 931B track loaders, 926 wheel loaders, etc., installed in the cylinder block camshaft seat bore, supporting the camshaft journal.
Assembly Fit: Interference fit with the cylinder block seat bore (interference 0.015-0.03 mm), clearance fit with the camshaft journal (cold clearance 0.05-0.08 mm). (mm), the locating lip and the seat bore locating groove transition fit to prevent circumferential rotation.

Installation and Replacement Points:

Before installation, clean the seat bore and journal to remove oil, carbon deposits, and burrs. Measure the seat bore roundness ≤ 0.01 mm, cylindricity ≤ 0.015 mm, and journal ellipticity ≤ 0.01 mm.

Use a special installation tool to press the bearing in, ensuring the locating lip is embedded in the seat bore locating groove and the bearing end face is flush with the seat bore end face. After pressing, check that the oil hole and cylinder oil passage are aligned and unobstructed.

After installation, measure the cold radial clearance: 0.05-0.07 mm for 3204/3206 engines, and 0.06-0.08 mm for 3208 engines. If the clearance exceeds the tolerance, the bearing or journal must be replaced.

Maintenance Cycle: Check oil pressure and metal shavings every 2000 hours. Disassemble and inspect bearing wear every 8000 hours. Replace the bearing if the alloy layer wear is ≥ 0.3 mm or shows peeling or burning.