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Plumb Your Vehicle - Select The Right Hoses & Fittings

Posted in How To: Body Chassis on January 21, 2015
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Plumbing is one of the most overlooked items on a vehicle. During a busy racing season, hoses seem to be the last item ordered when prepping a truck. This usually results in a last-minute phone call to a parts dealer to scramble an overnight order. If the hoses and fittings are not properly made for the application, you can seriously damage your vehicle.

Fluids can corrode the hose if not made of the proper materials, resulting in leaks and part failures. You want to get the proper indexing or direction of your hose as well as the correct degree for your connectors and fittings. The type of material your hose is made out of is critical to the application as well. You need to have a list of everything you need to save time and money. When building or prepping a vehicle for extreme off-road racing or even a weekend of prerunning, it’s important to make sure your plumbing is ready to perform.

Choose The Right Hose
Plumbing is found everywhere on the vehicle. Everything from brake lines, fuel from fuel cells, to hoses pushing fluids to critical engine parts, they’re everywhere and each is specialized for the application. It’s extremely important to use the proper hose as they are made of several different types of materials. In addition, you need to know the proper hose diameter for the application you are plumbing.

Hoses are made of different materials, such as these PTFE and steel braided hose lines.

Hose diameters are assigned an AN number, which is a standard used industry wide. Knowing that number can help you with the proper fitting for your hose. In the off-road industry, PTFE is commonly found on vehicles. PTFE stands for polytetrafluoroethylene. PTFE is a synthetic fluoropolymer of tetrafluoroethylene. The most well-known brand name of these PTFE-based formulas is Teflon, which was discovered by DuPont. Its applications include brake lines, gearbox lines, clutch cables, and steering lines. These lines are commonly found on off-road vehicles in sizes from -2 to -8. Several dealers will cut and bore the exact length and size you need specific to your application. High-pressure PTFE hoses are typically used in applications where a vacuum is needed or fluids are under pressure. In off-road those sizes are normally found in the -6 to -32 range. Typically, they are made with a stainless steel braid surrounding material.

It’s very important to check the specifications and pressure rating of the hose you are using. Sending the wrong amount of pressure through it can result in big problems. The last thing you want to experience is a hose bursting, collapsing, or cutting off fluid flow. The result will be damaged parts leaving you stranded.

Another type of hose commonly found in the off-road industry is HTP or High Temperature Polymer. These hose lines are used in non-pressurized situations. They are typically non-braided but can handle a high-vibration rate. Fuel, oil, and water are some of the fluids pushed through these lines. The stainless variety of HTP hoses can be used directly inside of fuel tank.

It’s important to remember hoses don’t last forever. Steel braids can come undone and insides can and will deteriorate over time. Contact your manufacturer or dealer to find out the life of the hose. Some will need to be replaced after a certain period of time and usage. Some dealers recommend refreshing your plumbing system every couple of years.

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Making The Connection
Choosing the correct connectors for a specific job are equally as important as selecting the proper hose. If the connector is not properly fitted to the hose, you will have fluid leaks. Connectors come in all shapes, directions, sizes, and, of course, materials. Some connectors come with Teflon seals while others, like brake lines, use mechanical interfaces to do the sealing. Many dealers like Brown & Miller Racing Solutions work with several manufacturers to build application-specific connectors. BMRS carries a connector that is designed to connect directly to a Dailey dry-sump oil pump. Knowing the exact connector for the application saves time and money.

How the connector is crimped to the hose and your end application makes a huge difference. Some dealers and manufacturers will rent out a crimping tool. To get away from crimping, compression hose connectors and fittings are available. These are ideal in a desert racing application when you are stuck in the middle of nowhere and have ripped a hole in a hose. You don’t need to have a crimping tool available. Just replace the hose and go. While crimping may seem more secure, the connector or fitting can usually only be used once. Some outfits, like BMRS will cut, prep hoses, and crimp ends on for no extra charge. That’s a deal you shouldn’t pass up.

Quick-connect fittings do not require the use of a crimping tool.

Another important factor to remember when selecting the proper connector is knowing how it needs to be clocked as some ends spin and some don’t. Clocking is the angle the connector will point in relation to the hose (and to the fitting on the other end of the hose). If you have a hose that needs to connect 90 degrees from one end to the next, proper clocking of the connector will help prevent the hose from bending or crimping thus not allowing for a full flow of fluid. Some applications require precise clocking down to the specific degree and many dealers can manufacture a connector with the specific clocking you need.

The material of the connector is also important. Keep in mind in off-road, severe vibration can shear off connectors and fittings if not made from proper materials. What may work on a hot rod won’t last off-road. A one-piece billet connector is likely to withstand the elements longer over a connector or fitting that is made from two pieces. Stainless steel fittings and connectors are more commonly found in off-road racing applications over the billet aluminum connector. However, one thing to watch for when using a steel fitting is the possibility of rust and corrosion. Brake fluids are known to pull moisture out of the air, even in dry desert conditions. Other exotic materials, such as titanium, are being tested for high vibration. Heating the end of a rubber hose can also help better fit your connectors, and sometimes you will find your hose is no longer round at the end but more of an oval shape. If the connector is round and the hose isn’t, leaks won’t be far away. The two have to fit as one to keep problems at bay; it’s as simple as that.

Fittings come in all shapes, sizes, and directions.
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Recommended Dealers And Manufacturers
We have compiled a list of reputable dealers and manufacturers to buy hoses, connectors, and fittings from. Keep in mind it may not always be cost effective to buy your parts from non-reputable dealers just because the price is cheaper. If the material is not quality and connectors or fittings are not properly quality controlled, you will encounter part failures resulting in additional costs on your vehicle.

Brown and Miller Racing Solutions (704) 793-4319
Phenix Industries (951) 780-9330
Howe Performance (619) 561-7764
Inline Tube (800) 385-9452
Fuel Safe (800) 433-6524
Summit Racing Products (800) 230-3030
Pyrotect (800) 669-2355
ATL (800) 526-5330
XRP (562) 861-4765
Eaton/Aeroquip (800) 386-1911
Crown Performance (760) 599-0090
Stage 8 Fasteners (800) 843-7836
C&R Racing (317) 293-4100
Ron Davis Racing Products (800) 842-5166
Jiffy-Tite (888) 605-7788
Holley (866) 464-6553
Canton Racing Products (203) 481-9460

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