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Master Cylinder Filler Cap, Tie Down, Fits Model 66, 1.25"-18 thread, 1" Wrench Size (TD48804)

$11.90
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At a Glance

  • SKU: TD48804
PRODUCT INFORMATION

Product Details

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

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