Matched Set Dispatch — Drive and alternator belts ship together under one part number set, verified against your engine serial to prevent tension mismatch during rebuild.
Technical Specifications
| Parameter |
Value |
| Part Number |
6726898 6675837 |
| Product Type |
Belt |
| Cross-Reference |
6726898 (reference only), 6675837 (reference only) |
| Machine Fitment |
Bobcat 753, 763, 773, S150, S160, S175, S185, T180, T190 |
| Condition |
New Aftermarket |
| Warranty |
3–12 months against manufacturing defects |
| Standards |
ISO |
Application Suitability
| Engine System |
Related Components |
| Accessory Drive (Bobcat 753, 763, 773) |
Tensioner, idler pulley, crankshaft pulley keyway |
| Alternator Charging Circuit (S150, S160, S175) |
Alternator bearing, mounting bracket, wiring harness |
| High-Load Drive System (S185, T180, T190) |
Belt guard, cooling fan pulley, water pump seal |
Why the Same Belt Part Number Fails on Adjacent Engine Serials
Verify the exact engine serial before ordering to avoid variant-specific mounting differences.
A common issue we encounter with the Drive & Alternator Belt Set engine rebuild process is assuming a single part number covers all production runs of a machine like the Bobcat S150 or T190. Even when the cross-reference 6726898 6675837 appears correct, mid-production changes in the accessory bracket or tensioner arm can render the belt length or rib profile incorrect for your specific unit. This leads to the machine sitting on the bench while a replacement is sourced [NEED_CITE: engine accessory drive configuration variations across serial ranges]. The cost isn't just the belt; it is the labor spent removing components to find out the fitment is wrong.

The Accessory Drive System Context
The Drive & Alternator Belt Set engine rebuild is not just a pair of rubber loops; it is the critical link between the crankshaft and the machine's electrical and hydraulic accessory systems. One belt typically handles the high-load drive for the water pump or hydraulic pump, while the alternator belt maintains the charging circuit. If these are not specified as a matched set for your specific Bobcat 753 or S185, the tensioner cannot balance the load, leading to premature wear on the alternator bearings.
System-Level Root Causes of Belt Failure
Belts rarely fail in isolation. Heat degradation from a slipping water pump, oil contamination from a failing crankshaft seal, or misalignment caused by a worn tensioner pulley are the actual killers of a Drive & Alternator Belt Set engine rebuild. When we supply this set, we look at the adjacent seals and bearings. If the root cause isn't addressed, the new belts will be destroyed within a few operating hours [NEED_CITE: root cause analysis of accessory drive belt failures].
Engineering the Matched Set
The primary advantage of this matched set is the uniform wear progression across the accessory drive. A new alternator belt paired with a stretched, glazed drive belt forces the tensioner to work at an angle, accelerating wear on the water pump bearing. These belts are manufactured to ISO standards for specific rib profiles and tensile cord strength, ensuring that the alternator output remains stable even under the high-heat conditions typical of a Bobcat T180 or 773 working in a quarry.

The Cost of a Mismatched Overhaul Kit
Installing a belt set without verifying the engine serial variant often results in a "close enough" fit that slips under load. This slippage generates excessive heat, which cooks the alternator's internal diode pack. The hidden cost is a second repair for the electrical system that could have been avoided by checking the engine build sheet [NEED_CITE: alternator failure caused by belt tension and alignment issues].
Why Source This Set From Our Engineering Team
Our technical team doesn't just pull a box based on a machine model; we verify the engine serial against the accessory drive layout. We offer a single warranty across both self-produced and qualified sourced supply lines. Whether you need a single matched set for an emergency rebuild or a distributor stocking plan for Bobcat service centers, we provide a single account for all eight core categories. We can supply the tensioner, idler, and adjacent seals in the same consignment to ensure the system is refreshed as a whole.
Documentation & Verification
- Commercial invoice listing both part numbers 6726898 and 6675837.
- Cross-reference sheet confirming interchange for Bobcat 753-773 and S150-T190.
- Quality inspection record verifying rib profile and tensile strength.
- Warranty terms covering manufacturing defects for 3–12 months.
- Packing photographs showing belt packaging and protection during transit.
- HS code and customs support for international engine parts shipments.
Installation & Rebuild Sequence
- Clean all pulley grooves to remove rubber residue before installing the new 6726898 belt.
- Check alternator mounting bracket alignment to prevent side-loading the 6675837 belt.
- Verify tensioner arm pivot movement is smooth and free of corrosion.
- Torque crankshaft pulley bolt to spec to prevent keyway shear.
- Run engine at idle for fifteen minutes to seat the belts before applying load.
Engine Serial and Rebuild History Required
To ensure this Drive & Alternator Belt Set engine rebuild matches your unit, please provide the engine serial number and any details of previous overhauls. This allows us to confirm if your Bobcat S175 or T190 uses a specific variant of the accessory drive system.
Frequently Asked Questions
Q: Should I replace both belts at the same time or can I replace one?
A: Always replace them as a matched set. A new belt running alongside a stretched companion will carry a disproportionate share of the load, leading to rapid failure of the new component and potential damage to the tensioner assembly on your Bobcat loader.
Q: What other components should I inspect when replacing these belts?
A: You must check the tensioner arm for bearing play, the idler pulley for smooth rotation, and the alternator mounting ears for cracks. Any misalignment in these areas will cause the new belt set to derail or wear unevenly within the first few hours of operation.
Q: Does my engine serial number affect which belt part number I need?
A: Yes. Bobcat loaders like the S150 and T190 underwent production changes that altered accessory brackets. Providing the engine serial ensures we send the variant that matches your specific pulley spacing and tensioner type.
Q: What causes these belts to fail prematurely?
A: The most common causes are oil contamination from adjacent engine seals, pulley misalignment due to worn bracket bushings, and a seized tensioner bearing. Replacing the belt without fixing the root cause will result in a repeat failure.
Q: Can I get a kit that includes the tensioner and related seals?
A: Yes, we supply system-level kits that include the matched belt set, tensioner, idler pulleys, and any adjacent seals required for a complete accessory drive refresh on your machine.