The HPS 1-1/2″ (38mm) ID, 1-3/4″ Long Black Silicone Reinforced Coolant Cap w/Clamp For Heater Vacuum Valve Water Port sits in the Hoses & Fittings department here, stocked and fitment checked.

Inner diameter must match the fitting exactly, since eyeballing sizes is how leaks begin. Keep petroleum away from standard silicone unless the hose is lined for it.
Ordering the long black silicone reinforced takes a minute and the confirmation reaches you straight away.
Our team knows the long black silicone reinforced well, so ask if anything about the specification is unclear.
Stock of the long black silicone reinforced is live on this page rather than estimated.
Shops order the long black silicone reinforced from us in volume because the data on the page is accurate.
If your build is unusual, tell us and we will confirm the long black silicone reinforced against it.
The long black silicone reinforced ships protected, because a damaged part helps nobody.
Drivers choose the long black silicone reinforced here for honest specification detail and quick dispatch.
What you are buying
- Material: Silicone
- Finish: Black
- Category: Universal Hose
- Price: $33.55 with free shipping over $99
- Availability: in stock, dispatched from the USA
Manufacturer specifications
The HPS Performance 1-1/2″ (38mm) high temperature reinforced black silicone cap is designed specifically to be installed on your cooling system. Vacuum caps have no reinforcement and are intended for vacuum and very little pressure. The HPS reinforced silicone caps are manufactured just like our reinforced silicone radiator hoses. While traditional rubber coolant cap might crack and cause coolant leak, HPS Performance high temperature 3-ply polyester reinforced silicone caps will withstand the high temperatures and pressures of your cooling system for years to come.
HPS Reinforced Silicone Caps are compatible for use with coolant, water, air, turbocharger bypass valve ports, vacuum ports, throttle body water ports, heater cores, and much more.
Technical Specification
Product Type: Reinforced Silicone Coolant Cap
HPS Part Number: RSCC-150-BLK
Temperature Range:- 65 deg. F to + 350 deg. F (177 deg. C)
Reinforced Layer: 3-ply Polyester
Inside Diameter: 1-1/2″ (38mm)
Color: Black
Wall Thickness: 4mm
Inside Length: 1-3/16″
Overall Length: 1-3/4″
UV and ozone resistant
Remark: HPS reinforced silicone caps are not compatible with fuel, oil, or any petroleum-based products.
- Material: 3-Ply Reinforced Polyester Silicone
- Color: Black
- Made of High Temperature 3-ply Polyester Reinforced Silicone. Maximum Temperature Rating: 350 deg. F (177 deg. C).
- Ideal for heavy duty pressure connections and provides excellent resistance for high temperature applications
- Compatible for use with coolant, water, air, turbocharger bypass valve ports, vacuum ports, throttle body water ports, heater cores, and much more.
- Inside Diameter: 1-1/2″ (38mm). Overall Length: 1-3/4″
- HPS reinforced silicone caps are not compatible with fuel, oil, or any petroleum-based products.
Come with a HPS Brand Stainless Steel clamp (match Size) to complete your project
Application:
HPS Reinforced Silicone Caps are Universal Fit that compatible for use with coolant, water, air, turbocharger bypass valve ports, vacuum ports, throttle body water ports, heater cores, and much more.
Remark:
Installation: Compatible with Water/Coolant ONLY, Not for Fuel/Oil
Product Content:
- 1 x Coolant Cap
1 x Clamp
The product does not come with manual/instruction, Professional Install Recommended
Cross Reference Number:
- RSCC-150-BLK, EMSC-40-60, RSCC150BLK, EMSC4060, 648044907550, 648044825656
If the application text leaves any doubt, message us with the VIN and we will rule on fitment before the box is sealed.
Keep shopping: Hoses & Fittings · HPS 4″ (102mm) ID, 4″ Leg Long Black 4-Ply Silicone 1/2″ Offset Coupler Hose · HPS 3.12″ (80mm) ID, 6″ Leg Long Black 4-Ply Silicone 1/2″ Offset Coupler Hose · full catalog
Finished surfaces are wrapped and hardware is bagged, so the part arrives ready to install.
When you want a second opinion that is not a parts store, read the NHTSA vehicle safety hub.
Before you order
How do I confirm this fits?
Our parts team confirms fitment before the box is sealed. Contact us with your vehicle details and we will settle it in advance.
How long does delivery take?
Dispatch is normally the same or next business day, and heavy items travel on freight with a booked delivery window.
What happens if it arrives damaged?
If the part does not fit, message our support desk with the order number and we will arrange an exchange or refund. Keep the packaging until the test fit is done.
How do you protect it in transit?
Lines and fittings are checked for pressure rating, inner diameter and ply count before shipping.
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