The Hydra Pro IV (models 433-820 and 433-821) is a gas-engine hydraulic airless sprayer rated at 2.5 gpm with a 500 to 3300 psi pressure range. Its largest tip is 0.050 in. with one gun, 0.035 in. with two and 0.029 in. with three. Titan's pump is the 185-551 and its motor is the 441-574. Parts and manuals remain available.
The Pro IV is the smallest-output Hydra in the older group, and it has its own pump, motor and hydraulic diagrams that do not match the Hydra M's. That matters at the parts counter: a number from a Hydra M diagram is not automatically a Pro IV part. Here is what Titan's Pro IV manual says about the sprayer, what it is listed for, and which pages to open when something wears.
What the Hydra Pro IV is
The Pro IV follows the Hydra layout: an engine drives a hydraulic pump, a hydraulic motor strokes the fluid pump, and the fluid pump moves the coating. Titan's Pro IV manual covers models 433-820 and 433-821, rates delivery at 2.5 gpm, gives a pressure range of 500 to 3300 psi, and gives a maximum of 50 cycles per minute.
The manual describes Titan's patented Severe Service fluid pump with a thick hard chrome finish on the rod and cylinder. It does not explain the difference between 433-820 and 433-821, and the material we have does not either, so check the data plate and call us with the model and serial number before ordering anything that could depend on the version.
Titan's current US gas airless listing shows the Hydra X, so we treat the Pro IV as an older model. We do not call it discontinued. Parts are on the site and the manual is on our manuals page. We do not give weight or engine service hours for the Pro IV because the sources disagree or differ from the Hydra X, so follow your own manual for engine intervals.
Tip sizes
Hydra Pro IV largest tip by gun count
| Guns | Largest tip Titan lists |
|---|---|
| 1 | 0.050 in. |
| 2 | 0.035 in. |
| 3 | 0.029 in. |
These are maximums, not recommendations.
At 2.5 gpm, the Pro IV has the least flow of the three older Hydras, and its tip ceiling is the lowest of the group: 0.050 in. with one gun, against 0.060 in. on the M 4000 and 0.075 in. on the M 2000. Tails or an hourglass pattern, in Titan's manuals, point to inadequate delivery or a worn tip. The manuals also call for a 100-mesh gun screen in place of the 50-mesh one when you spray with small tips.
Features Titan lists
- Variable pressure control.
- Tungsten carbide valve seats and self-adjusting packings.
- A hand-tight swivel foot valve.
- A rock-catcher inlet filter.
- A 50 mesh outlet filter.
Both filters have parts you can order. The inlet side is on the Pro IV siphon valve assembly page, which lists the 0509762A inlet screen and a long bent siphon tube. The outlet side is on the outlet accessories page, where the 920-004 filter element (50 mesh) and 920-927 long body filter are listed.
What it sprays
Dealer pages quoting Titan list architectural coatings, drywall mud, epoxies, mastics and elastomeric roof coatings for the Pro IV. Read that as the class of material the machine is aimed at. The coating's data sheet and your manual decide the tip, the pressure and the hose, and a coating that is acceptable on a larger machine may call for a smaller tip, or more gun time, on this one.
Pro IV parts by assembly
Where Pro IV parts are listed
| Assembly | Page | Key parts listed |
|---|---|---|
| Fluid pump | 185-551 Fluid Pump Assembly | 178-001A upper packing set, 183-001A packing set, 183-992 foot valve assembly, 185-984A displacement rod, 182-921A piston seat assembly |
| Hydraulic motor | Hydraulic Motor Parts (441-574) | 441-908 spool valve with sleeve, 441-149 backup ring, 441-148 O-ring, 441-005 spring trip |
| Hydraulic system | Hydraulic System Parts | 432-861 filter assembly, 433-026A heat exchanger assembly, 432-632 timing belt, 432-604 inlet strainer, 980-339A gas engine |
| Whole assemblies | Major Component Parts | 441-574A hydraulic motor, 441-185A motor pump, 185-551A pump assembly, 432-689A hydraulic hose set |
| Tank and cart | Tank Assembly and Mobil Kit | 434-622B Hydra tank, wheel, ground lug, fasteners |
| Bleed valve | Bleed Valve Assembly | 944-904 tungsten valve seat, 761-715 tungsten ball, 944-004 O-ring, 945-003 copper gasket |
Titan's manual links the common fluid pump symptoms to the same parts that fail on the other Hydras. A pump that delivers only on the upstroke has a lower foot valve ball that is not seating, so look at the 183-992 foot valve assembly first. One that delivers only on the downstroke has an upper ball that is not seating; clean and inspect the upper seat, and if the packing is worn, the Pro IV part is the 178-001A upper packing set. A chattering pump suggests solvent has swollen the upper packing. Because the piston rod must be smooth for new packings to last, inspect the 185-984A displacement rod whenever you open the pump.
For a bigger job the site lists 185-500 Major Pump Service Kit, and its catalog fitment reads "Hydra M and Hydra Pro series". It does not say which pump, and we do not list the kit's contents, so call (713) 931-0006 to confirm it matches the 185-551 before you order.
Fluid and care in brief
Titan's Pro IV manual calls for Coolflo, 430-361 by the gallon. Check the level daily against the Full mark on the dipstick, and change the fluid and the external filter every six months. The fluid change uses 5 gal of Coolflo. The upper packing takes Piston Lube (314-480), and the manual says not to substitute water or paint solvent. The hydraulic pump is not field-serviceable in the manual, which says to return the unit to Titan, so call us before buying any hydraulic pump part.
Pro IV parts discussed above:
The Short Version
The Pro IV is a 2.5 gpm, 500 to 3300 psi hydraulic sprayer with its own 185-551 pump and 441-574 motor. Keep to the tip limits, use the Pro IV diagrams rather than Hydra M ones, and start fluid pump work at the foot valve, upper packing and displacement rod.
Not sure a part fits your Pro IV?
Call (713) 931-0006 with the model number and serial number and our parts team will confirm the part before you order.
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