Tie Down Master Cylinder Cap w/ Bladder – Model 60 / 66 / 70 / 80 – 1-1/4"-18 Thread
Part Number: TD48804
Direct replacement master cylinder cap with internal bladder for Tie Down and Dexter surge brake actuators. Restores sealing, protects brake fluid, and stabilizes hydraulic pressure.
New replacement cap — intact bladder and sealing surface
Failed cap on Model 660 actuator — internal bladder deterioration (common failure point)
Underside threads and sealing flange — verify 1-1/4"-18 fitment
What Actually Fails
The failure is internal — not the threads.
The rubber bladder dries out, cracks, and allows moisture into the brake fluid, causing inconsistent pressure and degraded braking.
Important: The cap may look fine externally while already failing internally.
R&P Knowledge Hub
Replaces: Tie Down Models 60, 66, 70 series, 80. Cross-reference Dexter K68-538-00.
Fitment Check: 1-1/4"-18 thread and approximately 1.235" OD.
Pro Insight: Many actuators are replaced unnecessarily — restoring the cap and bladder often restores proper braking.
Features
- Internal bladder maintains sealed hydraulic system
- Prevents moisture contamination
- 1-1/4"-18 fine thread with ~1.235" OD
- Direct replacement for Tie Down / Dexter actuators
Specifications
| Spec | Detail |
| Thread | 1-1/4"-18 |
| Outside Diameter | ~1.235" |
| Cross Reference | Dexter K68-538-00 |
Compatible Master Cylinders
| Master Cylinder | Reference |
| F47260 | Tie Down 47260K |
| F47267 | Tie Down 47267K |
| F47268 | Tie Down 47268K |
| F47271 | Tie Down 47271K |
| F48854 | Tie Down 48854 |
| F48855 | Tie Down 48855 |
| F48875K | Tie Down 48875K |
| F48876K | Tie Down 48876K |
Included
| Qty | Item |
| 1 | Cap w/ Bladder |
