1VWHQ

HPS 5/8" (16mm) High Temp Reinforced Silicone Coolant Cap Bypass Heater

Name: HPS 5/8" (16mm) High Temp Reinforced Silicone Coolant Cap Bypass Heater
Brand: HPS
SKU: 1VWHQ
Price: 21.42 USD
Availability: InStock

HPS 5/8" (16mm) High Temp Reinforced Silicone Coolant Cap Bypass Heater

$21.42

$21.42 ~~$21.42~~

Color Black Blue Red

In stock

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Warranty Backed
Genuine Parts

Shipping Notice

Some oversized, heavy, or specialty items may incur additional shipping charges based on your delivery location. If this applies to your order, our team will contact you after checkout with the updated cost. Orders will not ship until additional charges are confirmed and paid.

HPS 5/8" (16mm) High Temperature Reinforced Silicone Caps are designed specifically to be installed on your cooling system. Regular 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. With 3 layers of polyester webbing for reinforcement, you can be sure that HPS 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. HPS reinforced silicone caps are not compatible with fuel, oil, or any petroleum-based products.

Technical Specification

Product Type: Reinforced Silicone Coolant Cap
Temperature Range: -65 deg. F to + 350 deg. F (177 deg. C)
Reinforced Layer: 3-ply Polyester
Inside Diameter: 5/8" (16mm)
Inside Length: 1-3/16"
Overall Length: 1-5/8"
Wall Thickness: 4mm
Color: Black, Blue and Red
UV and ozone resistant

Remark: Silicone hose is NOT compatible with fuel or oil.

Size Chart

Inside Diameter	Wall Thickness	Inside Length	Overall Length	Matching Clamp #
1/4" (6.5mm)	4mm	1-3/16"	1-1/2"	FIC-13
5/16" (8mm)	4mm	1-3/16"	1-1/2"	EMSC-10-16
3/8" (9.5mm)	4mm	1-3/16"	1-1/2"	EMSC-12-22
7/16" (11mm)	4mm	1-3/16"	1-1/2"	EMSC-12-22
1/2" (13mm)	4mm	1-3/16"	1-1/2"	EMSC-16-27
9/16" (14mm)	4mm	1-3/16"	1-5/8"	EMSC-16-27
5/8" (16mm)	4mm	1-3/16"	1-5/8"	EMSC-16-27
45/64" (18mm)	4mm	1-3/16"	1-5/8"	EMSC-20-32
3/4" (19mm)	4mm	1-3/16"	1-5/8"	EMSC-20-32
25/32" (20mm)	4mm	1-3/16"	1-5/8"	EMSC-20-32
7/8" (22mm)	4mm	1-3/16"	1-5/8"	EMSC-20-32
1" (25mm)	4mm	1-3/16"	1-5/8"	EMSC-25-40
1-1/16" (27mm)	5.5mm	2"	2-1/2"	EMSC-25-40
1-1/8" (28mm)	4mm	1-3/16"	1-3/4"	EMSC-25-40
1-3/16" (30mm)	4mm	1-3/16"	1-3/4"	EMSC-30-45
1-1/4" (32mm)	4mm	1-3/16"	1-3/4"	EMSC-30-45

If one of your stock coolant bypass caps were to fail and you are thinking about replacing it with a vacuum cap from your local auto parts store, keep in mind this will only mend the problem temporarily. Although they look the same, vacuum caps are made of vinyl or rubber with a low temperature rating not suitable for coolant temperatures.

The HPS Reinforced Silicone Coolant Cap is a permanent solution for your leaky coolant bypass and vacuum ports. Don’t wait until it is too late. Preventative maintenance with quality parts will save you time and money in the long run.

Engines are one of the most intricate pieces of a car. Because so much time is put into an engine's design, automakers find it beneficial to design engines suitable for multiple applications. Look at the GM LS/LT platform for example. If it comes from General Motors and has a V8, it is likely equipped with an LS or LT (or some other variant of Chevy small block). Although the engine can be shared, the vehicle size or space available in the engine may dictate the placement of certain components such as coolant plumbing. Rather than producing vehicle-specific engines, automakers save on development costs by applying this design philosophy.

The same engine from two different vehicles with entirely different coolant lines. The engine on the right provides coolant to the heater core via the port on the head, whereas the engine on the left blocks off the coolant port.

The factory installs rubber caps to close off ports where coolant hoses are not needed. The caps installed by the factory are one of the weakest links of any cooling system. Radiator hoses typically have a layer of fabric reinforcement between the rubber layers whereas rubber caps have no reinforcement at all. As rubber hardens and becomes brittle over time, the cap’s ability to hold pressure is reduced. With these caps under pressure for a long period of time, it can not end well. When we noticed this potential flaw, we took it upon ourselves to produce a cap that can hold up to the job while reaping the benefits of silicone.

Here is a stock rubber coolant bypass cap deteriorating with heat and age.

The construction of our reinforced silicone coolant caps (RSCC) is what sets this product apart from the competition. We use silicone instead of rubber for various reasons. Primarily, silicone has a wider operating temperature range (-65 F to +350 F) compared to EPDM rubber which has a temperature rating of -40 F to +275 F. Like our HPS silicone coolant hoses, we reinforce our coolant caps with 3 layers of polyester (compared to zero reinforcement from its factory counterpart). The added reinforcement prevents expansion under pressure and makes the RSCC stronger than traditional coolant bypass caps.

Close up cross section of the 3-ply reinforced HPS Reinforced Silicone Coolant Cap.

We have found many uses for The HPS RSCC during engine swaps, pressure testing, and race prep. Removing and bypassing the heater core is made easier with the reinforced silicone coolant cap whereas sourcing a suitable hose to loop the inlet and outlet ports can often be difficult. A popular (but controversial) mod is to bypass the coolant line to the throttle body to lower intake temperatures. The RSCC is not limited to the cooling system and can also be used to replace old and damaged vacuum port caps.

Our 2JZ-GE runs a Borg Warner S300 oil-cooled turbocharger. It does not need any coolant so the coolant port typically used to supply coolant to the turbocharger from the engine is now capped off with the HPS RSCC.

Returns

Prior to purchase, customers are responsible for confirming that the part is fully compatible with their specific application.

At FRSport, our goal is to ensure that you’re 100% satisfied with your purchase. If, for whatever reason, you are dissatisfied with your purchase, you can return it to us within 180 days of of placing your order. After thirty days, we reserve the right to determine return eligibility on a case by case basis due to the nature of automotive parts, fitments, expiration, and special order or made to order status, and international import and export rules, etc... We want to make sure you have what you need for your project, so please reach out to us and we will try to take care of you to the best of our ability. Please continue below for our terms and conditions.

Customer Service Hours:
Monday to Friday (excluding holidays)

Items that cannot be returned:

Electronics
Catalytic Converter / Exhaust / Downpipe / Y Pipe
Turbo / Supercharger kits
External body parts including body kits
Engine internals and valvetrain
Wheels, rims and tires
Most interior items (example: Seats, harnesses etc.)
Fittings and made to order lines
Coupler, hose, and piping components
Promotional products
Racing suits, shoes, and related clothing
Liquid Items
Any item that was a special order
Open Box / Used items

Returned or exchanged products must be brand new, unused, and uninstalled. Items should have all original manufacturer's packaging, materials, and accessories, including instruction booklets and packing inserts.

Damaged in transit & item shortages or incorrect items.

Claims for missing, incorrect items, or items damaged in transit must be submitted to us within 3 business days of receipt of merchandise. Please be sure to check all items once you receive them so that if there is an issue, you are able to notify us as soon as possible.

Returns Due to Merchandise Defect

All items sold by FRSport are warrantied only through their respective manufacturers. If you received a defective item, FRsport will facilitate the warranty process with the manufacturer to get you a replacement part. It is up to the manufacturer to make a decision on the claim. Higher-end brands usually have fewer issues and better warranty support, so keep that in mind when making your purchase decision. We have great working, direct relationships with many manufacturers; this ensures that you will get superior warranty support compared to other shops.

Refused / Undeliverable shipments

Any refused or undeliverable shipments that arrive back at our facility will incur all related shipping costs including return freight charges and any return-to-sender fees assessed by the shipping carrier, which will be deducted from your product refund.

Returns for Refund, Store Credit, or Exchanges

A Return Merchandise Authorization (RMA) number must be requested within 30 days of delivery of the product. Returns without an RMA number will not be accepted. RMA numbers will be valid for 30 days after it is issued, or as required, whichever earlier.

Items that are brand new, uninstalled/ unused, and in original manufactured condition as returned to us may be eligible for restocking fee waiver. Items that qualify will have NO RESTOCKING FEES with other items being subjected to a 20% restocking fee, excluding any shipping charges. This will be determined by us at the time you request for the RMA (return authorization) at which time you will usually submit pictures of the item for return approval. The actual (not free) shipping cost to send the item to you is not refundable.

For returns classified as “Buyer’s Remorse” or “Ordered Wrong Part/Size”, a 10% return processing fee will apply. Additionally, original shipping costs are non-refundable, as it is the buyer’s responsibility to ensure the part is correct for their application before purchasing. If a cancellation is needed, it must be requested before the order is processed or shipped.

The original manufacturer's labeled packaging should be enclosed within an outer shipping box. Please do not write or place shipping labels or stickers on the manufacturer's packaging.

Securely package the product and include the filled out Return Merchandise Form and a copy of the original invoice.

Ship the parcel back to us freight prepaid. We do not accept COD or freight collect shipments. We recommend a shipping method that provides tracking and insurance.

Shipping

Worldwide Shipping

We proudly ship internationally using trusted carriers including UPS, USPS, and DHL. Delivery can be as fast as 2 business days (transit time only and does not include processing). Delivery times do not account for weekends or U.S. holidays.

International Shipping Notes

Additional international shipping fees may apply based on the final dimensional size of the package after export clearance.

Customs duties, taxes, and brokerage fees are the responsibility of the buyer. FRSport does not collect or reimburse these charges.

Please check with your local customs office for applicable fees prior to ordering.

Order Processing

Orders for in-stock items are processed within 48 hours and typically ship the same or next business day. Tracking information will be provided once your order is dispatched.

Backorders and Pre-orders

Items not currently in stock are processed as backorders or pre-orders. Estimated delivery times are based on manufacturer updates and may vary. If a cancellation is approved, a 10% processing fee will apply.

Shipping to PO Boxes and APO/FPO Addresses

Only USPS can deliver to PO Boxes or APO/FPO addresses. Please select USPS at checkout if this applies to your order.

Refused or Undeliverable Shipments

Any shipment that is refused or returned to us due to an incorrect address or non-collection may be subject to additional shipping charges and a 20% restocking fee.

Damaged Shipments

All orders are carefully packed and inspected before shipping. If your package arrives damaged, please inspect it in the presence of the carrier before signing. A replacement or refund will be issued once the carrier has processed and approved the damage claim.

Shipping Transit Times

Transit time begins the day after your order is shipped. Delivery times are calculated in business days (Monday to Friday), excluding weekends and U.S. holidays. Guaranteed shipping services are based on the date the order is shipped, not the order date.