TMI HSW Control Valve Oil Seal - Marine Transmission Seal Component
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Control Valve Oil Seal for TMI HSW Marine Transmissions
This precision-manufactured oil seal is designed for TMI HSW marine transmission control valves, providing reliable sealing to prevent fluid leaks and maintain proper hydraulic pressure. Essential for transmission service, control valve rebuilds, and seal replacement.
Key Features:
- Control valve oil seal for TMI HSW marine transmissions
- OEM-quality seal material resists transmission fluid and heat
- Prevents fluid leaks at control valve location
- Precision-manufactured to exact specifications
- Maintains proper hydraulic pressure for shift control
- Essential component for transmission and control valve service
- Reliable sealing in demanding marine environments
- Ensures proper control valve operation
Function & Importance:
The control valve oil seal is a critical component that seals the control valve assembly in TMI HSW marine transmissions. The control valve directs hydraulic pressure to engage and disengage clutches for shifting. Proper sealing at the control valve is essential to maintain hydraulic pressure, prevent internal leaks, and ensure reliable shift operation. A worn or damaged control valve seal causes internal pressure loss, poor shift quality, and potential transmission malfunction.
TMI HSW Applications:
TMI (Twin Disc Marine Italy) HSW series transmissions are hydraulically-shifted marine transmissions commonly found in commercial and recreational vessels. The control valve is the heart of the hydraulic shift system, and proper sealing is critical for reliable operation.
When to Replace:
Control valve seals should be replaced during transmission rebuilds, control valve service, or when experiencing symptoms such as delayed shifting, poor shift quality, internal pressure loss, or transmission fluid leaks. Seals deteriorate over time due to heat, fluid exposure, and normal wear. Always replace control valve seals during any control valve disassembly or transmission rebuild.
Installation:
Clean seal grooves and mating surfaces thoroughly before installation. Inspect control valve bore and seal surfaces for damage, scoring, or wear. Lubricate seal with clean transmission fluid before installation. Install carefully to avoid twisting, pinching, or cutting the seal. Ensure seal is properly seated in its groove. Follow TMI service procedures for control valve assembly and adjustment.
Service Best Practices:
Never reuse old seals - always install new seals during control valve service. Replace all seals in the control valve assembly together. Use only OEM or equivalent quality seals designed for transmission fluid and operating temperatures. Test shift operation after service to verify proper control valve function.
Technical Specifications:
- Type: Control valve oil seal
- Compatible with: TMI HSW marine transmissions
- Part Number: 0634309621
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.