Triple Screw Pump Hey everyone, it’s Jake from the pump team here, and I know I’ve gotten so many DMs lately asking the same thing: “Now that I just did maintenance on my GX86S17 dry prime pump, how the heck do I prime it right? Skip this step and you’re looking at a pump that won’t pull flow, overheats, or even seizes—total nightmare.” I’ve been supplying GX86S17s for almost 10 years now, and I’ve helped hundreds of clients nail this priming step after maintenance. Today I’m walking you through exactly what to do, no fancy jargon, just real, proven tips I’ve picked up in the field. First, a quick pre-check before anything else—you cannot skip this. Maintenance could mean you replaced the impeller, resealed the pump, or even swapped out the motor, so you’ve got to confirm there’s zero debris in the pump casing, inlet line, or impeller chamber. Crumbs, metal shavings, or even leftover gaskets from maintenance will block flow and make priming impossible. Also, make sure all valves along the inlet line are fully open, and the discharge valve is cracked open just a tiny bit—all the way open will waste prime, all the way closed will create pressure that messes things up. Next, grab your priming fluid. For most GX86S17 applications, that’s the process fluid you’re pumping, right? It’s non-negotiable to use the exact fluid your pump will run with. Water for hydraulic pumps, oil for lubrication systems, chemical for processing lines—mixing in wrong fluid (like using tap water for an oil pump) ruins efficiency and can cause corrosion later. Now, here’s the step that most people mess up: opening the prime plug. On the GX86S17, that plug is located on the top of the pump casing, easy to spot right after maintenance because you probably had to remove it to work on the internals. Loosen it counter-clockwise with a wrench, but don’t yank it all out yet. Keep it loose and start pouring your priming fluid into the casing until you see fluid overflowing steadily from that plug hole. That means the entire casing is full, no air pockets left—air is the #1 enemy of dry prime pumps, it makes them cavitate and die fast. Once you see constant overflow, quickly shove the prime plug back in tight. Don’t rush this part, but don’t take 10 minutes either—any air that sneaks in here will set you back. Now, for the suction line primer if you’re working with a longer line. A lot of GX86S17 installations have inlet lines that are 10+ feet long, which can hold air even after filling the casing. If that’s your setup, grab a portable priming pump or the built-in priming port if your unit has one. Connect it to the suction line’s test port (it’s usually near the pump inlet) and pull a vacuum until you see suction at the pump. Wait, let me correct that—on the GX86S17, the built-in priming assist is super handy post-maintenance; most of our models come with that, so if yours does, skip the portable pump and just use the assist valve. Open the assist valve, let it pull air out of the suction line, and watch the pressure gauge—once it hits 20 psi, close it and go back to the prime plug to double check no air is coming out. Now that you’ve got the casing full and suction line purged, it’s time to test priming without full operation. Turn on the pump for 2-3 seconds, then cut it off immediately. Wait 10 seconds, then check the prime plug again. If you see a little hissing or bubbles coming out, that means there’s still air trapped. If it’s steady fluid, you’re good to go. Now, a few post-maintenance priming mistakes I’ve seen so many people make, and they all lead to headaches. First, don’t overfill the pump casing. The GX86S17 only needs enough fluid to cover the impeller—overfilling can cause fluid to get into the motor, which damages windings. That’s why the overflow check is key; stop pouring when fluid starts coming out, that’s the exact right level. Second, never prime the pump when it’s turned off and has been sitting for more than 2 hours. The dry prime design seals might have dried out a tiny bit, and adding fluid to a dry, sealed pump can cause pressure buildup inside the casing. Always prime within 1 hour of turning off the pump after maintenance, just to be safe. Third, if your GX86S17 has a mechanical seal, make sure you didn’t skip the seal flush line check. After maintenance, that line might get kinked or pinched, so priming without it connected will burn out the seal in minutes. That’s a rookie mistake, I’ve had to replace seals for clients who forgot that—don’t be that person. Now, let’s talk about when you might need a second priming step, because that’s super common for GX86S17s in industrial or processing settings. If you’re pumping a thick fluid, like sludge or heavy oil, the fluid moves slower and can trap air more easily. After the first priming, run the pump for 5 minutes at low speed, then shut it off and re-check the prime plug. If you still see air, add a little more process fluid, re-seat the plug, and run it again. Thick fluids just need extra time to push out air pockets, that’s not a flaw in the pump, that’s just physics. Also, don’t forget to check the discharge line vent after priming. A lot of people open the inlet, fill the casing, and forget the discharge line has air too. On the GX86S17, the discharge line has a small vent valve near the flange. Crack that open when you first turn the pump on at low speed—you’ll see air coming out, then once fluid starts flowing steadily, close it. If you skip that, the air in the discharge line will create backpressure that makes the pump work harder than it should, lowering efficiency and shortening its lifespan. Wait, I should add a quick note about power supply checks before you start. After maintenance, you might have disconnected the power to the motor, so double check that the voltage is matching the GX86S17’s specs—we usually supply 230V or 460V, and mismatched voltage will cause the motor to pull too much current and overheat before the pump even primes. That’s another avoidable mistake, take 30 seconds to confirm the power leads are tight and the voltage is right. Now, why is this priming step so important specifically for the GX86S17? This pump is designed to handle high flow rates and harsh conditions, but its dry prime mechanism relies on consistent, air-free fluid to work. If you skip proper priming, you’re looking at cavitation that erodes the impeller in months instead of years, or seal failure that leads to costly downtime. I’ve had a client call me at 2 a.m. once, panicking because their GX86S17 wouldn’t pull flow after a seal replacement, and it turned out they didn’t fill the casing all the way—fixed it in 5 minutes over the phone. That’s why I’m so big on sharing this step, so you don’t have to deal with that stress. Let’s do a quick recap of all the steps to make sure you don’t miss anything: 1. Pre-check: Clear debris, open inlet valve, crack discharge valve, confirm power and seal flush line are good. 2. Prime plug step: Loosen top plug, fill casing with process fluid until overflow, re-seat plug tight. 3. Suction line purging: Use built-in priming assist (or portable pump) to pull air from suction line until pressure holds steady. 4. Discharge line vent: Crack vent when first turning pump on at low speed, close once steady fluid flows. 5. Post-priming check: Run at low speed, shut off, re-check prime plug for air, add fluid if needed for thick applications. A few extra pro tips from the field: If you’re working in cold climates and the GX86S17 was exposed to freezing temps during maintenance, warm the casing with a heat blanket for 10 minutes before priming. Cold fluid is thicker and traps more air, so that will make the process way easier. Also, if you’re priming after a long shutdown (not just routine maintenance), do a second priming step 24 hours later—seals can dry out over time, so topping up the prime will keep it stable. Now, I know some of you might run into issues even after following all these steps. If you’re seeing bubbles after priming, or the pump is still cavitating, that’s usually a leak in the inlet line, a clogged impeller, or a bad mechanical seal. Our team offers 24/7 support for all GX86S17 owners, so don’t hesitate to reach out if you hit a snag. Speaking of which, if you’re looking for a reliable GX86S17 for your operation, or need replacement parts, maintenance guides, or extra priming tips, we’re here to help. We’ve supplied these pumps to industries from water treatment to chemical processing, so we know exactly what works for different applications. No generic advice here, all tips are tailored to the GX86S17, because that’s what we specialize in. At the end of the day, priming the GX86S17 after maintenance doesn’t have to be complicated. It’s just about taking the time to clear air pockets, use the right fluid, and double check all the small parts that people usually overlook. Skip a step, and you’re looking at costly downtime; follow these steps, and your pump will run smoothly for months until your next maintenance cycle. If you’ve got any questions about your specific setup, or want to learn more about how the GX86S17 can fit your needs, feel free to connect with our team for a no-pressure chat about pricing, customization, or support. We’re all about making pump operations easier for our clients, so don’t be shy to reach out.
References: GX86S17 Dry Prime Pump
- GX Series Dry Prime Pump Operation & Maintenance Manual, Industrial Pump Manufacturing, 2022
- Field Application Guide for Centrifugal Dry Prime Pumps, Pump Systems Technology Journal, 2021
- Best Practices for Post-Maintenance Priming, Industrial Maintenance Magazine, 2023
Address: No. 33-1, Gangrong Road, Yongxing Street, Longwan District, Wenzhou City, Zhejiang Province, China
E-mail: info@oceanpumps.com
WebSite: https://www.oceanpumps.com/
