How Hydraulic Contamination Control Protects Uptime, Safety, and System Performance
Hydraulic contamination control protects uptime, safety and system performance by keeping dirt, air and moisture out of the system at the point where attachments connect. In this episode of In Good Company, host Lisa Kilrea of WSI eResults talks with Jay Prins, Product Engineer at Stucchi USA, about what contamination really costs and how the right couplers, procedures and partnerships prevent it.
Here’s a glimpse of what you’ll learn
01:19 Why contamination during hydraulic attachment changes can quickly turn into downtime, component damage, productivity loss, and major repair costs.
04:49 How flat-face coupler technology helps reduce fluid loss, air inclusion, and contamination compared with traditional poppet-style couplers.
08:41 Why air and moisture should be treated as hydraulic contaminants, especially in applications that require precise actuator control.
11:31 What a real contamination control program looks like, from cleanliness specifications and component handling to maintenance, filtration, and field practices.
20:37 What operators should inspect, clean, and check at the connection point before making a hydraulic attachment connection.
24:29 How trapped pressure leads to unsafe improvisation, why connect-under-pressure solutions matter, and what operators can do when that capability is not available.
In this episode…
Contamination that enters during an attachment change rarely stays at the coupler. Jay explains how dirt can reach motors, cylinders and pumps, turning a small coupler repair into a week or two of downtime, and how a sticking valve can become a safety issue for the operator.
The coupler design is the first line of defense. Stucchi flat-face couplers provide zero-spill performance with virtually zero fluid loss per disconnect. Because the faces are flush, operators can wipe both halves clean before they connect, which helps keep dirt, air and moisture out of the hydraulic system.
Hardware alone is not a program. Jay walks through a complete contamination control approach: a system cleanliness specification based on ISO 4406, cleaning new components before assembly, regular fluid sampling and filtration, and simple field habits such as inspecting both coupler halves and using caps and plugs. For mixed fleets, he recommends documented procedures for each machine and a team-wide approach.
Lisa and Jay also cover residual pressure, one of the most frustrating problems in the field. Forcing a connection or loosening a coupler to spill oil puts operators at risk and opens the system to contamination. Select Stucchi connect-under-pressure couplers are designed to connect under residual pressure. When that capability is not available, Jay shares safer ways to bring the pressure down.
The conversation closes with what separates a technical partner from a transactional supplier, and why strong relationships with OEMs, fleet managers and operators lead to better long-term results. To discuss contamination control for your equipment, contact Stucchi USA.
Frequently Asked Questions
What does contamination during hydraulic attachment changes cost?
If contamination damages only the quick coupler, the parts can cost over $50, and a coupler change commonly takes over three hours, so labor can bring one failure to a couple hundred dollars. If contamination reaches a pump, motor or critical valve, those components can cost $1,000 to $2,000 or more to replace, and the equipment can be down for a week or two.
Can hydraulic contamination create safety issues?
Yes. Contamination can cause a valve to stick. If an operator actuates a valve that moves an arm or a bucket and the valve does not close properly, the load may not stop when it should.
Which downstream component usually fails first from contamination?
The coupler itself is usually robust. When contamination gets downstream, it usually affects the motor or the cylinder actuators first, because those components do the heavy work. Replacing them can keep the equipment out of service for a week or two.
Why do flat face couplers reduce fluid loss and contamination compared to poppet couplers?
A poppet coupler has a large cavity, especially on the female half, that collects dirt, and each connection traps oil between the two halves. That oil spills at disconnection, and air enters the line at connection. Flat face couplers are designed to minimize spillage, have no cavity to collect contamination, and can be wiped clean on both faces before you connect.
What should OEMs specify to prevent contamination problems?
OEMs should specify a coupling solution that minimizes contamination ingress from the start, such as a flat face design. It costs more up front, but it pays dividends in fewer warranty claims and better protection for expensive components like pumps, motors and cylinders.
Why is air a contaminant in a hydraulic system?
Hydraulic fluid is incompressible, but air is compressible. Air in the system creates sponginess that reduces the operator’s control of loads, which matters most in precise applications such as die casting presses or excavator buckets. The reservoir is the largest entry point for air, and the quick coupling is the second.
What does a real contamination control program look like?
It starts when you specify the equipment: set a cleanliness level for the whole system with the ISO 4406 code. Clean new components before assembly, because they may not be clean from the factory. Maintain the fluid with regular samples, filtration and fluid changes. In the field, wipe couplers clean before you connect and after you disconnect, and use caps and plugs.
How do you run contamination control across a mixed fleet?
Create documented procedures for each type of equipment, with checklists and a routine maintenance schedule for each brand or machine. Make contamination control a team responsibility, and teach each team member how to use and clean the equipment and why it matters.
What should an operator do at the connection point before connecting?
Check both the machine side and the attachment side for leaks, since a leak while disconnected shows which coupling needs attention. Remove the caps and plugs and make sure the valve faces are clean, wiping them with a rag or using compressed air if needed. Inspect for damage, then align the couplings and connect them.
What is the most common mistake that causes contamination?
Skipping the inspection and cleaning of both coupler halves to save time during an attachment change. Attachments often sit on the ground or in dirt, and connecting uncleaned couplers introduces contamination that can damage the system.
Why are dust caps and plugs important?
Caps and plugs are inexpensive but keep dirt, contamination and moisture off the coupler interface while it is disconnected. That means less cleaning and less risk of corrosion, and many include a lanyard so they stay with the coupler. In corrosive environments, such as coastal areas with salt air, material choice also matters, because rust is a form of contamination.
What is the right way to handle residual or trapped pressure?
Do not force the connection with tools or loosen the coupler to spill oil. Forcing risks safety and damages the coupler, and spilling oil opens the system to contamination and environmental concerns. The best solution is a connect-under-pressure coupling. Without one, let the attachment cool so the pressure drops, or, on attachments with cylinders, extend the cylinder rod to add volume and lower the pressure.
Are low-spill couplers becoming a requirement?
Yes. In agriculture, marine and other environmentally sensitive applications, check the spillage value in the coupler specifications and keep it as low as possible. The construction industry has largely moved to couplings with virtually zero spillage, and some agriculture manufacturers are considering the same move.
Transcript
In Good Company podcast. Host: Lisa Kilrea, WSI eResults. Guest: Jay Prins, Stucchi USA. This transcript is lightly edited for readability: filler words and false starts are removed. Timestamps mark where each section begins.
[00:01] Introduction
Announcer: Welcome to In Good Company, where relationships drive results, with your host, Lisa Kilrea. In each episode, we explore how great leaders build trust, inspire teams, and turn meaningful connections into real success.
Lisa: Hi, I’m Lisa Kilrea, host of In Good Company, where relationships drive results. Today’s episode is sponsored by WSI eResults. We help manufacturers and distributors build the strategic foundation they need for AI-driven digital growth, including SEO, content and multichannel programs that drive measurable results. To learn more about WSI, visit www.wsi-manufacturingmarketing.com.
Today I’m joined by Jay Prins. Jay is with Stucchi, a global leader in hydraulic quick-connect solutions, known for its flat face, zero-spill technology designed to improve reliability, reduce contamination, and support performance across demanding hydraulic applications. Jay, welcome to In Good Company. I’m so glad you’re able to join me today.
Jay: Thank you for having me.
[01:24] The Real Cost of Contamination
Lisa: Let’s start at a high level before we get into the technology. What does contamination during hydraulic attachment changes actually cost an operator in real-world terms: downtime, component damage and dollars?
Jay: That can vary, but contamination can definitely wreak havoc on systems. At a basic level, if you’re just looking at the quick disconnect, which is Stucchi’s product and our expertise, the quick disconnect itself can be damaged by contamination. Contamination can get in and hold some of the moving components open. That creates a poorer sealing surface, and the coupler can be prone to leaks and to trouble connecting and disconnecting.
In terms of dollars, at a base level you might have to replace your components, so over $50. In terms of downtime, it’s common for a quick coupler change to take over three hours. Once you factor in that service time and labor, you could easily be over a couple hundred dollars just for that failure.
Now, if the quick disconnect let that contamination in, and it’s now affecting other components in your hydraulic system, the cost can go significantly higher. If contamination reaches your pump, motor or another critical valve component, those components can cost upwards of $1,000 to $2,000 to replace, and the downtime of your equipment goes up significantly. You might have to wait a week or two just for a spot in a shop, and then the labor to replace those components is much greater. So it’s a big impact on your hydraulic system and on your productivity.
Lisa: Productivity. Are there any safety issues?
Jay: Yes. If contamination is affecting critical components, that’s a concern, because you’re trying to keep a contained, repeatable system without variances in the fluid. Safety issues can come up if contamination causes a valve to stick. When you actuate a valve that’s moving an arm or a bucket, and you want it to stop, you need it to stop. If contamination is there and the valve doesn’t close properly, that can create a safety issue for the operators.
Lisa: Which obviously everybody wants to avoid.
Jay: Yes.
Lisa: When something does go wrong, what is the most common downstream component to fail, and how does that replacement cost compare to a coupler upgrade?
Jay: The coupler itself is usually pretty robust against contamination failure. If contamination gets downstream, it’s probably going to affect your motor or cylinder actuators first. Those actuators are the components doing the heavy lifting and the actual work, and once they fail due to contamination, your equipment might be out for a week or two just to replace them.
[04:55] Poppet vs. Flat Face Couplers
Lisa: For listeners who may not be familiar with traditional poppet-style couplers, what changed when flat face technology arrived, and why does that design matter so much for preventing fluid loss and contamination?
Jay: The poppet coupler is one of the oldest quick couplings around; it’s probably the first one designed. It has a couple of drawbacks. Especially on the female side of the connection, there is a very large cavity that is a magnet for contamination and dirt. On top of that, with that valve design, every time you connect and disconnect, a volume of oil gets trapped between the two halves. When you disconnect, you spill that much oil, and when you connect, you introduce that much air into your hydraulic line.
So the poppet style just wasn’t optimized for minimizing spillage. Once you have spillage, you’ve got oil in a cavity that attracts dirt, and on your next connection, all that dirt gets connected into your system. It was the first coupling designed and it’s been widely adopted, but our leak-free, dripless flat face connectors have a lot of advantages over it.
The flat face style is designed to minimize spillage. It’s designed not to collect contamination in a cavity. And it’s designed so that when you go to connect, you can easily clean both surfaces with a rag. When you do connect, you’re really minimizing contamination entering your system.
[06:52] What OEMs Should Specify
Lisa: From an OEM perspective, what should equipment manufacturers be specifying from the start, rather than letting this become a fix-it-later problem in the field?
Jay: As an OEM, you really need to be looking at a good solution that minimizes contamination ingress. It will pay dividends, even though it’s a more expensive solution. OEMs will have fewer warranty claims later, and not just on the quick disconnects themselves, which are considered wear parts. A flat face solution will really protect your more expensive critical components, like your pumps, motors and cylinders.
[07:37] Air as a Contaminant
Lisa: When most people think about contamination, they think of dirt and debris, but air inclusion is also a contaminant. Can you explain how connection design affects whether air enters the system, and why that matters?
Jay: Air and moisture are two often-forgotten contaminants in a hydraulic system. When you have air and moisture in your system, you’re losing some of your control of the fluid. One of the basic principles of fluid power is that your fluid is incompressible, and air is compressible. When you’re dealing with high pressures and trying to control loads with your valves, any air pocket or sponginess will affect the operator’s ability to run the equipment efficiently. So it’s important to minimize the amount of air in your system. The biggest entry point for air is probably your hydraulic reservoir, and second is your quick coupling location.
Lisa: Very interesting. Are there specific applications where air inclusion becomes especially destructive?
Jay: Any time you need precise control over your actuators. In a die casting application, for example, you need precise control of your press. And you might have issues operating an excavator, where you need precise control of your bucket.
[09:22] What a Real Contamination Control Program Looks Like
Lisa: A lot of operators look at this problem and ask, “What coupler should I buy?” But you’ve mentioned that hardware alone is not the answer. What does a real contamination control program look like?
Jay: A contamination control program really starts at the beginning, when you’re specifying your equipment. First, identify the cleanliness level you need to achieve for the whole system. Every component has different sensitivities to contamination. The ISO committee developed a code, ISO 4406, that provides a way to measure contamination levels and create specifications everyone can work toward. So at the front end, designing your components to a cleanliness spec that you have to meet is most critical.
Second, when you purchase new components, don’t assume they are clean from the factory. It’s important to clean them and to be careful during assembly not to introduce contamination.
Beyond that, once your system is together, it’s important to have regular maintenance on your fluid: fluid samples, sometimes kidney-loop filtration during use, changing your fluids regularly, and monitoring contamination levels as you operate.
The last part is your best practices for how you use the equipment. At the connection point, make sure you wipe your quick couplers clean before you connect, and wipe them clean after you disconnect so there’s no oil residue on them. The use of caps and plugs is big, because they keep moisture and contamination off the couplings when they’re disconnected.
Lisa: I love your thorough answer. Thank you.
[11:31] Mixed Fleets
Lisa: Many operators run mixed fleets: different brands, different vintages, different attachments. How do you build a contamination control program that works consistently across that kind of variety?
Jay: With a mix of equipment, you can’t use the same filtration equipment, or even the same fluids, across every machine. The biggest thing with a mixed fleet is to have documented procedures for each type of equipment, then create checklists and a routine schedule to maintain each brand or each machine individually.
The second most important thing, in my opinion, is to tackle this as a team. You can’t have one person in charge of all your contamination problems; it’s up to the whole fleet team. Educating each team member on how to use the equipment, how to keep it clean, and why it matters is pretty big.
[12:38] The Role of Relationships
Lisa: That’s a perfect segue, because this show is about how relationships drive results. From a relationship perspective, how important is it for Stucchi to work closely with OEMs, fleet managers and operators when implementing the kinds of programs you’ve been describing?
Jay: It’s important to have a good relationship, and to explain the importance of topics like this, because we want what’s best for our customers. Whether it’s an OEM or an end user, Stucchi is trying to make sure we offer the best solution we can for each application. Having a relationship where we can offer our technical opinion and expertise, and have the conversation that weighs the benefit of a better valve solution against the cost, is pretty important.
Lisa: What does that relationship typically look like when you’re helping a customer move from a reactive approach to a more proactive, system-level strategy?
Jay: With a reactive approach, we usually get the call when tensions are pretty high, because the user has downtime happening. They need a replacement part; they’re in emergency-action mode. In that case it’s important to provide a high level of service and responsiveness, but at the same time keep the overarching goal in mind. If they’ve had a failure with the product they’ve been using, it’s also an opportunity to talk about a better solution. So while being sensitive to the situation, we steer the conversation toward what the best product might be, especially because downtime can be an opportunity to install a better solution, like a flat face coupler.
[14:51] Best Practice at the Connection Point
Lisa: Let’s get practical. Walk us through what an operator should be doing at the connection point in the field before making a connection.
Jay: Before making a connection, first check for leaks on both sides: on the machine and on the attachment. A leak while disconnected is a pretty good indicator of which coupling might be failed or compromised, and where you need to focus your maintenance. Once you connect them, it’s difficult to tell which side is the culprit.
Second, make sure all the interfacing surfaces are as clean as possible. Remove the caps and plugs first, then check that the valve interface is clean. If it’s not, we recommend wiping the surfaces with a rag or paper towel. If compressed air is available, blowing out the contamination is good too.
Next, inspect for overall damage. Quick disconnect components sometimes get dragged on the ground and can have dings and other damage.
If that’s all clear, you can align the two couplings and connect them. The connection method varies by product type: we have push-to-connect and thread-to-connect solutions. However you need to make that connection, go ahead at that point.
Lisa: What is the single most common mistake you see operators make, the one that causes contamination without them realizing it?
Jay: When they need to switch attachments, they want to do it as quickly as possible and get back to work. So the biggest mistake is skipping the step of inspecting and cleaning both sides. The attachment is often lying on the ground or in the dirt, and if you don’t clean the couplers before you connect, you introduce contamination that can damage the system.
[17:18] Dust Caps, Plugs and Materials
Lisa: You’ve mentioned dust caps and plugs. They’re pretty simple-looking accessories. What makes them more important than people give them credit for?
Jay: Some of them are just a plastic cap, and they’re very inexpensive, but they offer huge value in protecting against contamination. They’re easy to install, and many have a lanyard so they stay with the coupler and you don’t have to go looking for them. Caps and plugs keep dirt and contamination off the interface, so you don’t have to worry about cleaning as much. They also keep moisture off the valves, which helps prevent corrosion.
Lisa: Are there specific environments where material choice becomes critical?
Jay: Any time you’re dealing with a corrosive environment: moisture, and especially coastal areas where you’re exposed to salt and salt fog. Material choice is pretty critical there. Rust and corrosion can be a form of contamination, and they can accelerate product failure very quickly.
[18:39] Residual (Trapped) Pressure
Lisa: In my research, I read that one of the problems operators run into all the time, but rarely talk about, is residual or trapped pressure in the line. They can’t connect, so they improvise, and that improvising creates contamination. What is the right way to handle it?
Jay: If you’re an operator dealing with trapped pressure, it’s probably one of the most frustrating things that can happen. These are quick connects, and if you can’t get them together because of that pressure, they’re no longer quick.
A lot of in-field improvised solutions involve forcing the connection together with tools. When you do that, you risk your safety, because you’re connecting a live pressure system, and that pressure can be released if there’s a failure. Using tools can also damage the quick disconnects, making them difficult to connect afterward, even without pressure.
The other common way people relieve pressure is to take the quick disconnect off, spill some oil to relieve the pressure, and then reinstall it. At that point you’ve opened your system to the environment, creating another entry point for contamination, let alone the environmental concerns of spilling oil.
The best way to connect with residual pressure is to use a connect-under-pressure coupling or solution. These exist for that very reason, and they allow easy connection with residual pressure in a safe way.
Lisa: What should an operator do when their equipment does not have connect-under-pressure capability?
Jay: Residual pressure is most often generated by a change in temperature. So, if possible, relocate the attachment or store it somewhere that will bring the temperature down. As the temperature comes down, the pressure will also come down, and once it’s low enough you’ll be able to connect.
On certain types of attachments, mainly those with cylinders, you can also relieve pressure by manually actuating the cylinder so the rod extends. Extending the rod creates additional volume, and when that volume is created, the pressure comes down.
[21:28] Spillage, Regulation and Low-Spill Requirements
Lisa: For listeners working in industries like agriculture, marine or environmental applications, there’s increasing regulatory pressure around hydraulic fluid release. How is that changing what equipment owners need to specify?
Jay: When specifying a quick coupler, look in the coupler specs for the column or feature labeled “spillage.” Spillage is how much oil is spilled with every connection and disconnection. In any sensitive application, like agriculture, marine, or anything that affects the environment, you want to minimize spillage as much as possible. Even if you’re careful about capturing that residual oil every time, it’s not a guarantee. The best approach is not to have it in the first place.
Lisa: Are you seeing zero-spill move from a nice-to-have to more of a requirement?
Jay: Definitely. The construction industry has made a pretty good pivot to non-spill couplings, and we’ve seen a couple of agriculture manufacturers seriously consider it as well. It’s becoming more of a requirement than a nice-to-have.
Lisa: That’s what I thought you would say.
[22:51] Technical Partner vs. Transactional Supplier
Lisa: Again, this show is about relationships driving results. From your perspective, what separates a transactional supplier from a true technical partner in this space?
Jay: Someone who is willing to look at the solution regardless of cost, and look for the best solution: the one that will bring the most value.
Lisa: How do strong relationships between Stucchi and its customers impact performance, reliability and long-term success?
Jay: Our relationships impact long-term success because once you have a success with someone, you can build on it and keep growing. The lessons learned, and the next applications and opportunities, can become great partnerships that bring more and more value.
[23:50] Where to Learn More
Lisa: Jay, thank you so much for a great conversation. We’re not done yet, but before we wrap up, where is the best place for people to learn more about Stucchi, and where can they connect with you?
Jay: We have a website, www.stucchiusa.com. It’s a great place to see an overview of our company. There are white papers, case studies, and other applications where we’ve found success and brought a lot of value. It also has all of our products and product series, if you’re looking for a specific product. Beyond that, you can call our office, which will put you in touch with one of our technical specialists, and we can start a conversation from there.
Lisa: And where can they connect with you, Jay?
Jay: Usually through our general sales inbox, or by calling the office. I’m also on LinkedIn and other business social media.
Lisa: So, Jay Prins, if they’re looking for you on LinkedIn.
[25:12] A Mentor Who Made a Difference
Lisa: Before we close: when you think about a customer, partner or mentor who has had a lasting impact on how you approach your work today, who comes to mind, and what did you learn from that relationship?
Jay: There have definitely been a couple of engineers I’ve worked with who have had a big impact on me. Namely, I’d say Gianmarco Gotti. He also works for Stucchi, at our headquarters in Italy. He’s been working in the industry his entire career and is a huge wealth of knowledge. From his mentorship, I learned to review all the details and not let certain questions go unanswered, because we have the experience to know they’re critical and shouldn’t be glossed over.
Lisa: That’s a great example.
[26:10] Closing
Lisa: Jay, this has been a wonderful conversation about contamination control, system performance, and how the right approach at the connection point can have a significant downstream impact. Thank you for joining me, and thank you to our listeners for being here.
If there’s one takeaway from today’s conversation, I would say it’s this: contamination control is not just a maintenance issue. It’s a system-level decision that directly impacts reliability, cost and performance. And while the technology matters, the real results come from aligning the right equipment, procedures and partnerships.
Jay, thank you so much for joining us today. And to our listeners, thank you for spending time with us. I look forward to being in good company with you again next time.
Announcer: Thanks for listening to In Good Company, where relationships drive results, with Lisa Kilrea. Be sure to follow or subscribe so you never miss an episode. Until next time, stay connected and keep building relationships that drive results.