Stop Fighting Push Lock Hoses

When it comes to complete aggravation, installing a push lock hose onto a barbed fitting comes close to the very top of the list. It doesn’t matter if it’s a large, hydraulic hose or small plastic tubing, pushing it all the way onto the fitting is often a frustrating, time-consuming process, if not impossible.

At Koul Tools we believe that the easiest possible method of assembling push lock hose onto a barbed fitting is with our EZ-ON Hose Press.

Now, if you only have one or two hoses to install, spending $250 on a tool might not be worth it…

…but if you assemble a lot of push lock hoses, this tool will save you money.

Push Lock Hose Assembly

We created the EZ-ON Hose Press for push lock hose and fittings that are used in the automotive industry, but soon after it hit the market, we started getting inquires from the industrial, agricultural, and biotech industries.

The most common question we get is “Will your tool work with our hose and fitting” and our answer is always “yes” because the vise will clamp both straight and angled fittings

…and if it doesn’t, it can be modified to work with almost any type of fitting.

This is important because it’s the angled and elbow fittings that are often the hardest to install because you can’t just push them up against a bench or the floor. Also, a lot of hose assembly tools on the market aren’t designed to work with angled fittings.

How to Install 1/4″ to 1″ Push Lock Hose

The EZ-ON Hose Press is so simple to use, it almost makes installing push lock hose fun.

Here are the steps:

  1. Secure the fitting in the stationary vise.
  2. Clamp the hose into the travelling carriage.
  3. Push the hose over the first barb to get it started.
  4. Use an impact gun or ratchet with a 17mm socket to drive the hose onto the barb.

Watch a quick video where we install the Fragola Series 8000 Push-Lite Race Hose:

Before there was a push lock hose assembly tool available, people would install this hose by using heat and/or lubrication. To heat the hose, you have to boil water or use a heat gun.

Heating the hose can be problematic because:

  • You can overheat the hose. This can cause the hose to become too brittle and could lead to failure.
  • It’s not very convenient. What if you install hoses on location?
  • You can burn yourself. Okay, not likely. But handling boiling water has its risks. Why even put injury into the equation?

How to Install 3/16″ Plastic Tubing

Recently, we’ve had a lot of medical device companies come to us to help solve their problems of installing the small, plastic style tubing that is used on their medical devices.

At the time, we were not familiar with this style of tubing and fitting, so we got some samples for testing. When we received the samples, we couldn’t believe how difficult it was to work with. The tubing is so small and so stiff that we could barely get them half way onto the barb.

Although the EZ-ON Hose Press was originally made for 1/4″ to 1″ hose sizes, the clamps that come with it are removable, so we were able to design clamps that work on 3/16″ tubing.

In this video, we use custom clamps to install Entegris Teflon Tubing onto a Beswick barb orifice fitting:

How to Install Nylon Fuel Lines

The nylon fuel line that is used for fuel injection presented a big challenge to install with our EZ-ON Hose Press. Because it is small and flimsy when compared to rubber hose, it would collapse or “accordion” when installing it.

To accommodate this, we fabricated a custom vise and clamps that prevent the hose from collapsing and it installs it easily. We will have a vise for both the straight and elbow fittings.

Watch this demo video where we install a Dorman Nylon Fuel Line:

How to Remove Push Lock Hose

Removing push lock hose is no easy task either. This is by design of course, because you want the hose to stay securely on the fitting. If you need to remove an old hose from a barbed fitting, see our post on how to remove a push lock hose without damaging the fitting. We have a great tip on how to avoid using a knife so you don’t damage the fitting, or worse yet, slice your finger.

What People are Saying

“Wow, just WOW!

In a world full of disappointments, this bad-arsed tool does satisfy. Built like a tank, will last my lifetime, and makes a painful and difficult chore a breeze.  Pays for itself in one morning of quick and easy hose assembly. Grips so nicely that it will seat hose already covered in woven fiberglass fire sleeve. Too koul.”

– Robert Taylor

“Best $250 I have spent in quite some time. I ran fittings for an entire fuel injection conversion in about 20 minutes! Priceless!”

– Matt Sanford

“This tool is AMAZING!!!! We use the push locks on everything here at Nerd Rods from out custom fuel systems, to power steering return lines (not the pressure power steering line obviously) and oil cooling systems on the transmission and engines. Heck we probably use 12-30 ends on each chassis leaving our shop and at 14-20 chassis a year, that’s A LOT of ends.

I did the first car with the push lock ends and had bruises on the insides of my palms after two days of fighting with them to get them all seated. Got this tool and did a whole car in a matter of hours. It paid for itself on the first car (in time alone). Here we are 20-30 chassis projects later and well over 300 ends, probably closer to 400, and we’ve finally worn out the little plastic jaws (just call, they have replacements if you use it that much).  It’s a killer tool everyone should own, hands down!”

– Russell @ Nerd Rods

More About the EZ-ON Hose Press

The EZ-ON Hose Press is a great option for assembling push lock hoses. It’s size and shape allow you to work in a small area or to take it with you to a job site. All you need is an impact gun or ratchet with a 17 mm socket.
Here are the details:

  • Installs 1/4″ to 1″ push lock hose.
  • Works with both straight and angled fittings.
  • Includes plastic vise jaw inserts to protect fittings.
  • Made of investment cast steel.
  • Comes with a custom carrying case.

You can purchase the EZ-ON Hose Press on our online store by clicking the image below:

Barb fitting installation tool

How to Clamp Braided Stainless Steel Hose and Fitting

posted in: AN Hose Assembly | 2

Clamp braided stainless steel hose and fitting

Over the years I’ve done my share of AN hose assembly projects. These jobs can be a piece of cake or a major pain in the neck. As most of you know already, the biggest hurdle to cross is inserting the hose into the socket. If you don’t get a clean cut on your braided stainless steel hose it can be a nightmare getting it into the the fitting. That’s why I invented the AN Hose Assembly Tool to funnel the frayed ends into the nut.

Once you get the hose into the socket and installed all the way to the threads, most of the ugly stuff is behind you. However, there is one more potential obstacle that can be just as frustrating. When you go to screw the fitting into the nut, the AN hose can push out of the end you just installed it into.

Recently, I discovered a way to clamp braided stainless steel hose with AN vise jaw inserts. Place the inserts so that they are sticking half way out of the vise. As you can see in the photo, both the fitting and the hose are secured tightly. You probably don’t need to mark the hose anymore, but it’s never a bad idea just to be safe.

How to Fix Leaky Brake Line Fittings

How to Fix Leaky Brake Line Fittings

posted in: Hard Line Sealing | 0

Is your brake line leaking where the flare joins the fitting? If so, it is important to address the issue immediately and with a legitimate solution.

When it comes to leaky brake line fittings there are plenty of band-aid fixes that could end up being disastrous. I was fed up with these unreliable methods when I was attempting to repair a leaking brake line in my Packard Coupe, and that is when I began looking for a real way to solve this issue.

Why Brake Lines Leak at the Flare

Brake lines will leak at the flare when there is a poor connection with the seat of the fitting. This type of leak is commonly known as a weep. It can be caused by a ding in the fitting, but most of the time it is the result of a tiny imperfection in the flare that occurs while flaring the tube. No matter what flaring tool I used, I never got a clean, concentric finish that enabled the flare to seat with the fitting. And it didn’t matter if I was using steel lines with a 45° double flare or stainless steel lines with a 37° single flare.


A before and after image of flared tubing

The Case for Lapping Flared Hard Lines

Lapping is a tried and true practice that goes back 100 years. Even with the best equipment, mechanics always lapped engine valves to ensure they wouldn’t leak. It occurred to me that lapping the flare on the brake line could get the tube to seat with the fitting.  I decided to apply this principle to flared tubing, and it fixed the leak I was getting in my Packard. This was how I came up with the idea for the Surseat Flare Lapping Tool.

How to Use the Surseat Flare Lapping Tool

1. Unscrew the brake line from the fitting.
2. Clamp the appropriate collet around the line.
3. Connect it to the Surseat and secure it with the lock spring.
4. Spray some lubricant to the lapping head before using it.
5. Rotate the lapping head back and forth about 6-10 times.
6. Clean and inspect the flare. There should be a smooth, concentric finish. If not, repeat step #5.
7. Remove the brake line from the Surseat and reconnect it to the fitting.
8. Bleed the brakes and check the seal.

How to Check for a Leak Where the Flare Joins the Fitting

If you have your brake or fuel line out of your vehicle, there’s an easy way to check to see if there’s a leak at the fitting. First, plug the end of the tube that you are checking by screwing in a cap flared tube nut or anything similar that will seal off that end of the tube. You can also purchase Earl’s Performance Pressure Test Kits if you don’t have anything that will work. Next, submerge the line in water and run air through the opposite end of the tube. If bubbles appear at the fitting, the seal is no good. Repeat the lapping process until you get no bubbles.

The bubbles on the left indicate a leaky brake line fitting
On the left you can see the bubbles coming out of the fitting indicating a bad seal between the flared tube and fitting. The bubble-free fitting on the right indicates a good seal.

Damaged Fittings

If a leak persists after lapping the flare with the Surseat, inspect the conical surface of the fitting for imperfections. Most of the time, the issue of sealing hard lines is with the flare, but there could be a problem with the fitting. A fitting can get damaged by over tightening them with an imperfect flare, by dropping something on them, or some other accident where you end up with a ding. Although it is not that common of an occurrence, it can be very problematic. For instance, what if you damage a fitting that’s welded into a tank?


Fitting with score in the conical surface
A leak in the fitting could be the result of a score in the conical surface of the fitting.

What People are Saying

“I have been double flaring brake lines for street rods for 30 years with great success. My latest project, a 32 Ford Roadster had 6 fittings that I could not get to seal. I kept trying to tighten the fittings, hoping the joint would seal. I don’t know if it’s the quality of brake lines or just me, but I couldn’t get the brake system to not weep. I remember seeing this tool at the Street Rods Nationals, and decided to order one, and see if it would solve my problems. I disassembled the entire brake system and lapped every flare with the Koul Tool P45. I reassembled the brake system and didn’t have a single issue. I will lap every fitting I make from now on just to make sure I get a proper seal on my brake fittings. The tool is easy to use and certainly performs.”

– Bill Kantos

“I’ve used several of your tools before, and have found all of them to be real time savers!
I had a master cylinder to brake line leak with my ’55 Chevy that your line lapper resolved. It seems that no matter how carefully I flare the tube, sometimes I still have a leak. It seems that the cause of this is roughness of the flare. Your lapping tool removes this making for a positive, leak free seal. Thanks again for saving me time, and trouble!”

– Ed Coyer

More About the Surseat

The Surseat flare lapping tools have a precision, diamond dust coated lapping head that will clean up tubing flares to enable them to seat with the brake line fitting. They come in three different models: The P-51 has interchangeable 37° and 45° lapping cones and will do 3/16 to 1/2 inch tubing. The P-45 and P-37 models are designed specifically for brake lines. The smaller size and rectangular shape make it easier to work in tight spaces inside the car. The P-45 and P-37, also known as ‘Minis’, are great for fixing a leak in an existing brake or fuel line, but they can also be used to lap-in your lines when installing them in order to avoid getting a leak in the first place.


Brake line sealing tool


How to Easily Install Braided, Stainless Hose to the Threads of AN Fittings

posted in: AN Hose Assembly | 4

It seems to have become more difficult lately to install braided stainless hose all the way to the threads of AN fittings. Although it’s not as problematic as inserting it into the fitting, it can be burdensome and needs to be addressed.

The first time we realized this was an issue was when we bought new hose for our KOUL tool demos at the SEMA Show last fall. The hose was noticeably stiffer and far more difficult to install. Then, after receiving comments from customers about this problem, we decided to look for an easy way to get the hose fully installed.

There are three types of AN hoses that we found to be more difficult to install than others. The first culprit is the -16 braided stainless hose we use. It’s extremely stiff, making it hard to push all they way to the threads. Next, our -6 nylon braided hose is too flexible, making hard to get any force behind it. Finally, any of the smaller sizes can be difficult because it’s just hard to fully grip them.

Install braided stainless hose in a snap

1. Use the Koultool to get your hose started.

Use the Koultool to get your AN hose started

2. Clamp the hose into AN vise jaw inserts.

Clamp braided stainless hose into AN vise jaw inserts

3. Twist and push the fitting onto the hose with a palm wrench.

Use a palm wrench to install braided stainless hose to the threads of AN fittings

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