TSL vs Pump Armor: The Confusion That Destroys Contractor Sprayers Every Spring

By Nnanna Otuonye, SprayersAndParts.com  |  2026  |  Equipment Maintenance

Every spring, the same repair comes through our Houston facility. A contractor brings in a Graco Ultra 395 or Ultra Max II 695. Stored through winter. It won’t prime, or primes weakly and loses pressure almost immediately. In a significant number of these cases, the diagnosis includes evidence that Pump Armor was used in the TSL wet cup — or the machine was stored with the wrong fluid in the fluid path.

This is the guide that prevents that visit.

The Two Products and What They Actually Do

TSL — Throat Seal Liquid

TSL is an oil-based lubricant for the packing nut wet cup on contractor-class Graco machines — the Ultra 395, 495, 595, Ultra Max II 695/795, Pro 210 ES, and LineLazer 3400. These machines have an exposed piston rod that passes through the packing nut on every pump stroke. The TSL wet cup keeps the rod coated with lubricant throughout every stroke, lubricating the rod-to-packing interface and preventing dried material from building up on the rod surface.

The official Graco manual says to fill the TSL cup to the fill line before every use. Not once a week — before every use.

Pump Armor

Pump Armor (part 17S980) is a water-soluble, anti-corrosion pump conditioner for Graco Magnum homeowner models — the X5, X7, and ProX17. These machines use an embedded pump design with no exposed wet cup. Pump Armor is run through the entire fluid path at end of use or for seasonal storage. It displaces residual paint, coats the internal fluid path with an anti-corrosion layer, and keeps the pump internals protected during storage. It is not a wet-cup lubricant.

Why the Confusion Happens — and What It Costs

Both products are Graco-branded. Both are sold in similar sizes. Both are associated with maintenance. Completely understandable that someone new to contractor machines would not know which applies to their equipment.

Pump Armor in a TSL Wet Cup

Pump Armor is water-soluble. In a TSL wet cup on a contractor machine, the water-soluble base can evaporate during storage, leaving a residue that doesn’t lubricate the rod properly. In warm-weather storage it can become tacky. On first startup, the machine runs with an inadequately lubricated rod, accelerating packing wear. This is why machines stored incorrectly fail their first pump test of spring.

TSL in a Magnum Homeowner Machine

TSL doesn’t flush out cleanly with water the way Pump Armor does. Residual TSL in the pump fluid path of a Magnum machine can cause issues with the first paint loaded after storage, particularly water-based latex that doesn’t mix with oil residue.

The Rule — Written Down Where You Won’t Forget It

The Visual Test: Does Your Machine Have a Wet Cup?

Look at the pump on your machine. On contractor machines with TSL requirements, you’ll see a small cylindrical reservoir — the wet cup — at the base of the piston rod, typically with a yellow or clear indicator ring showing the fluid level. If you see this reservoir, your machine uses TSL. On Magnum homeowner machines there is no such reservoir.

If you’re still not sure which fluid applies to your specific model, the Graco paint sprayer parts catalog lists maintenance fluid requirements alongside every Graco model — search your model number and confirm before the next service.

Seasonal Storage Procedure

Magnum X5/X7/ProX17 — End of Season

1. Flush machine thoroughly with clean water until output runs clear
2. Run a full reservoir of Pump Armor through pump, hose, and gun
3. Leave Pump Armor in the machine for storage — it coats and protects
4. Store above freezing

Ultra 395/695 Family — End of Season

1. Flush machine thoroughly with clean water until output runs clear
2. Flush with mineral spirits to clear water from the fluid path
3. Fill TSL wet cup to full before final storage
4. Store above freezing

Repairing Damage from Incorrect Storage

If a machine has been stored improperly and now shows packing damage, the repair is typically a packing kit replacement. For the Ultra 395: 18B260 packing kit from our Graco Ultra 395 parts page ($65–$85) plus the 239922 intake valve seat ($28) if there’s any priming issue after the rebuild. In more serious cases where Pump Armor caused packings to adhere to the rod, inspect the rod surface for scoring before installing new packings — a scored rod ruins new packings prematurely.See More

Both TSL and Pump Armor (17S980) are available on our Graco accessories and maintenance supplies page in 8oz, 1qt, and 1gal sizes — same-day shipping from Houston, TX. Call 713-931-4102 if you’re not sure what size your wet cup holds orpackings—a keep on hand for your operation.