Shopping the HPS 1-1/2″ (38mm) ID, 1-3/4″ Long Black Silicone Reinforced Coolant Cap w/Clamp For Heater Vacuum Valve Water Port? Everything you need to choose correctly is on this page.

Inner diameter must match the fitting exactly, since eyeballing sizes is how leaks begin. Use constant tension or lined clamps so the hose surface survives heat cycles.
Drivers choose the long black silicone reinforced here for honest specification detail and quick dispatch.
Buyers comparing the long black silicone reinforced will find the specification detail on this page rather than in a catalog footnote.
The long black silicone reinforced listed here is checked against your vehicle before dispatch.
Every long black silicone reinforced order goes through the same fitment review.
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.
Quick specs
- 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
Give us the VIN and we will check trim, engine option and drive type, the three details that break fitment.
See also: Hoses & Fittings · HPS 1.25″ (32mm) ID, 6″ Leg Long Black 4-Ply Silicone 1/2″ Offset Coupler Hose · HPS 2.38″, 2.75″ (60mm, 70mm) ID, 6″ Leg Long Black 4-Ply Silicone 1/2″ Offset Reducer Hose · full catalog
Orders are checked against your vehicle details before they are sealed, then dispatched quickly.
For safety and service guidance from outside the aftermarket, see the fuel economy maintenance guidance.
Quick answers
How do I confirm this fits?
Send your VIN or your year, make and model and our fitment desk confirms the part against manufacturer data before it ships. The check is free and usually answered the same business day.
How long does delivery take?
Same business day dispatch applies to orders placed before the early afternoon cutoff, with tracking that updates at every carrier scan.
How do returns work here?
Parts are covered against defects for the period stated on this page, and non defect returns follow our standard returns window.
What happens before my order ships?
Lines and fittings are checked for pressure rating, inner diameter and ply count before shipping.
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