✅ This item is normally regularly stocked. Shipping times may vary depending on availability. Please contact us to confirm stock and shipping times. You will receive tracking details once the item has shipped.
Description
LMI AutoPrime Liquid End Replacement Kits for Chlorine Metering Pumps Losing Prime or Dosing Inconsistently
The LMI AutoPrime liquid end replacement kit replaces the entire wet end of your LMI chlorine metering pump in one shot. Each kit ships pre-assembled with the AutoPrime degassing head, Liquifram diaphragm, suction and discharge valves, AutoPrime bleed valve, injection check valve, foot valve with strainer, 4-function discharge valve, and all tubing and ferrules. The AutoPrime system continuously vents trapped chlorine gas back to the supply tank, eliminating the air lock that causes prime loss on sodium hypochlorite service.
Key Features
- Complete wet-end replacement. The LMI AutoPrime liquid end replacement kit includes pre-assembled AutoPrime head, Liquifram diaphragm, all check valves, injection assembly, foot valve, 4-function valve, and tubing with ferrules. Nothing else to order.
- AutoPrime degassing eliminates chlorine vapor lock. Three check valves (suction, discharge, AutoPrime bleed) continuously vent trapped gas from sodium hypochlorite back to the supply tank. The pump stays primed automatically.
- Clear machined acrylic head lets operators confirm diaphragm action and chemical flow visually without disconnecting tubing.
- A 4-function discharge valve provides anti-siphon protection, pressure relief, line drain, and priming aid in one integrated assembly.
- Chlorine-rated wetted materials: Acrylic/PVC head, Ceramic ball checks, Fluorofilm Liquifram, Polyprel seals. Rated for 12.5% sodium hypochlorite.
- Fits LMI LiquiPro Series B, C, B9, and C9 pumps. The LMI B9 HI Series chlorine metering pump and the LMI C HI Series chlorine pump both use these AutoPrime liquid ends from the factory. This kit replaces that same assembly.
Materials of Construction
| Component | Material |
|---|---|
| Pump Head | Machined Acrylic (clear) |
| Fittings | PVC |
| Ball Checks | Ceramic |
| Diaphragm | Fluorofilm Liquifram |
| Seals | Polyprel (TFE/P, Aflas) |
| Check Valve Accessory | PVDF / Polyprel |
| 4-Function Valve | Included |
| Tubing | Polyethylene (1/4", 3/8", or 1/2" OD per kit) |
| Chemistry Compatibility | 12.5% sodium hypochlorite, hydrogen peroxide, off-gassing chemistries |
Kit-to-Pump Compatibility
Match your pump model suffix to the correct LMI AutoPrime liquid end replacement kit:
| Kit | Size (Tubing) | Fits Pumps | Series |
|---|---|---|---|
| LE-D50HI | 0.5 (1/4" OD) | Models ending in 450HI | B, C, B9, C9 |
| LE-D60HI | 1.8 (3/8" OD) | Models ending in 460HI | B, C, B9, C9 |
| LE-D90HI | 0.9 (3/8" OD) | Models ending in 490HI | B, C, B9, C9 |
How to find your liquid end designation: Check the silver data plate on the front of your pump. Model format is [Series][Drive]-[Liquid End], e.g. B121-D90HI. The last section (D90HI) is the liquid end. Match it to the table above. Contact our team with your full model and serial number if you need help.
What's In Each Kit
Every LMI AutoPrime liquid end replacement kit ships complete:
- AutoPrime pump head (machined acrylic, pre-assembled with internal check valves)
- Liquifram diaphragm
- O-rings and seals (multiple types and sizes)
- Suction check valve assembly
- Cartridge valves
- Injection check valve with 1/2" NPT connection
- Injection valve cartridge
- Ceramic weight
- Foot valve with integrated strainer
- AutoPrime discharge cartridge, shuttle valve, and cartridge valve
- 4-function valve assembly
- Suction and discharge tubing (16 ft polyethylene)
- AutoPrime return tubing (10 ft)
- 4-function valve tubing (6 ft)
- Tubing connection kits with ferrules (multiple sets)
- Ball check valve fittings (single and double)
- Liquid end hardware (screws, nuts, washers)
How the AutoPrime Liquid End Works
The AutoPrime liquid end has 5 elements: head, diaphragm, suction check valve, discharge check valve, and AutoPrime bleed valve.
When the diaphragm pulls back, the chemical enters through the suction check valve. Trapped gas from sodium hypochlorite off-gassing enters with the fluid. On the forward stroke, gas rises to the top of the head and vents through the AutoPrime bleed valve back to the supply tank. A small amount of fluid (10 to 20 percent of output) recirculates each stroke. The remaining chemical discharges to the process.
The pump stays primed automatically. For optimal performance, keep stroke length above 50% and use stroke speed as the primary capacity adjustment.
Maximum suction lift: 5 feet.
Flooded suction: fluid level should not exceed 3 feet above the suction check valve.
When to Replace the Liquid End vs. Repair with an RPM Kit
Cleanflow stocks two levels of LMI pump maintenance parts for chlorine service. Choosing the right one depends on what is actually wrong.
LMI Pro Pac RPM Repair Kit: Replaces the wear parts inside your existing liquid end: O-rings, shaft seal, Liquifram diaphragm, check valve cartridges, valve seats, springs, and pump head screws. Your existing pump head, valves, and tubing stay in place. Choose the RPM kit when the pump head is intact with no visible cracks and the issue is worn seals or degraded check valves. RPM kits are part of annual preventive maintenance.
LMI AutoPrime Liquid End Replacement Kit: Replaces everything from the pump head to the foot valve. All new: AutoPrime degassing head, diaphragm, all valves, injection assembly, tubing, and ferrules. Choose the liquid end kit when the acrylic head is cracked or clouded, the pump has persistent prime loss after an RPM rebuild, or you are converting a standard liquid end to AutoPrime to solve chronic vapor lock on sodium hypochlorite.
Not sure? If the pump runs but doses inconsistently, start with an RPM kit. If the head is damaged or prime loss persists after rebuild, the LMI AutoPrime liquid end replacement kit is the right call.
Applications
Operators replace LMI chlorine metering pump liquid ends on pumps deployed in:
- Municipal drinking water chlorination (12.5% sodium hypochlorite)
- Wastewater effluent disinfection
- Swimming pool and aquatics chlorination
- Cooling tower biocide feed where vapor lock recurs
- Hydrogen peroxide dosing in advanced oxidation systems
- Any LMI pump application where the liquid end is cracked, clouded, or has failed multiple RPM rebuilds
Why Order LMI AutoPrime Liquid End Kits from Cleanflow
Cleanflow is an authorized LMI distributor stocking AutoPrime liquid end replacement kits for sale across Canada and the United States. Three chlorine-rated kits (LE-D50HI, LE-D60HI, LE-D90HI) ship from our Winnipeg warehouse. Free shipping over $199 CAD within Canada. The US orders ships directly. Call 1-866-335-1078 or email [email protected].
Buy LMI AutoPrime Liquid End Kits Online from Cleanflow
Select your kit (LE-D50HI, LE-D60HI, or LE-D90HI) and add to cart. Cleanflow is an authorized LMI distributor shipping across Canada and the United States. If the pump head is still intact and you only need seals and diaphragm, browse LMI Pro Pac RPM repair kits instead. For the full LMI parts and pump catalog, visit our LMI collection. Call 1-866-335-1078 to confirm which kit fits your pump model.
Frequently Asked Questions
How do I know which LMI liquid end replacement kit fits my pump?
Check the silver data plate on the front of your pump. The model number ends with the liquid end designation (e.g. B121-D90HI). Match the last section to the compatibility table: LE-D50HI fits 450HI, LE-D60HI fits 460HI, LE-D90HI fits 490HI. Contact our team with your full model and serial number if needed.
Should I replace the full liquid end or buy an RPM repair kit?
If the acrylic head is intact with no cracks or clouding and the pump just needs new seals, an LMI Pro Pac RPM kit handles that. Replace the full liquid end when the head is damaged, prime loss persists after RPM rebuild, or you are upgrading to AutoPrime to solve vapor lock on sodium hypochlorite.
Will this kit convert my standard liquid end to AutoPrime?
Yes. These are complete LMI AutoPrime liquid end replacement kits. If your pump has a standard (non-degassing) LiquiPro liquid end, this kit replaces the entire assembly with AutoPrime. The AutoPrime head has three check valves instead of two and a return line that vents gas back to the tank. Your drive end stays the same.
What chemistries are these kits rated for?
The HI suffix indicates chlorine-rated materials: Acrylic/PVC head, Ceramic checks, Fluorofilm Liquifram, Polyprel seals. Rated for 12.5% sodium hypochlorite, hydrogen peroxide, and other off-gassing chemistries. For non-chlorine chemistries, Cleanflow stocks general chemistry liquid end kits with different materials.
What LMI pump series are compatible?
LMI LiquiPro Series B and C, including electronic B9 and C9 variants. The AutoPrime datasheet also lists Roytronic A, AA, and P compatibility, but Cleanflow's stocked kits use LiquiPro connections. Confirm with our team for Roytronic models.
How long does the liquid end replacement take?
The kit ships pre-assembled. Remove the old liquid end from the drive, mount the new assembly, connect suction, discharge, and AutoPrime return tubing. A trained technician completes the swap in 30 to 60 minutes following the LMI instruction sheet included with the kit.
Does the kit include tubing and ferrules?
Yes. Each kit includes 16 ft suction/discharge tubing, 10 ft AutoPrime return tubing, 6 ft 4-function valve tubing, and multiple sets of connection kits with ferrules. Tubing OD varies by kit. Ceramic weight, foot valve, and injection valve also included.
What is Cleanflow's return policy on liquid end kits?
30-day return on unused, original-condition kits. Submit returns at returns.cleanflow.net. LMI manufacturer warranty applies. Keep original packaging. Contact [email protected] or 1-866-335-1078.
✅ This item is normally regularly stocked. Shipping times may vary depending on availability. Please contact us to confirm stock and shipping times. You will receive tracking details once the item has shipped.
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