"LineLazer 3900" is not one machine. It covers the III, IV and V generations, built over roughly two decades, with different displacement pumps, drive housings and engines. Ordering by the name alone is the number one cause of wrong parts on these stripers. Find the model number on the machine label first. The IV and V 3900 use displacement pump 277069; the III uses a different fluid section entirely.
Line stripers are the one category where ordering parts by model name reliably goes wrong. A painter with a 395 can say "I have a 395" and get close enough. A striping crew saying "I have a 3900" has told you almost nothing, because Graco has sold a machine called the 3900 across three distinct generations with substantially different internals.
This page sorts that out first, then covers the components that actually wear on a striper rather than on a paint sprayer.
1. Which Generation Do You Actually Have
Go to the machine, find the model number on the label, and work from that. Not the name on the shroud.
LineLazer III 3900
Earliest of the threeDistinct drive and pinion housing assemblies from the later machines.
- Pinion housing assembly 245715
- Drive housing assembly 245442
- Frame 245246
- Handle 245224
LineLazer IV 3900
Models incl. 248862, 248863, 249008, 24M605, 24M607Where the 277069 pump and 287xxx drive family appear.
- Displacement pump 277069
- Bearing housing 287714
- Connecting rod 287719
- Drive housing 287467
- Pinion housing 287463
- Frame 287623
LineLazer V 3900
Current, model 17H450Shares the 277069 pump family. Engine and mounting differ from the IV.
- Pump repair kit 277069
- Engine, 4.0 hp 108879
- Engine mount plate 15F583
- Pump pin 15F855
- Retaining spring 119676
Graco documents the 3900 and 5900 together, so a single parts page often lists both. Within that page the part numbers diverge: engine 108879 is the 4.0 hp unit for the 3900 while 114530 is the 5.5 hp unit for the 5900, and pump pin 15F855 is 3900 where 15F856 is 5900. Read the qualifier in the description column, not just the reference number.
2. Pump and Fluid Section
The displacement pump on a striper does the same job as on a paint sprayer, but the duty cycle is different. Striping is long continuous runs rather than start-stop wall work, so packings see sustained rather than intermittent load.
| Ref | Component | Part | Applies to |
|---|---|---|---|
| 21 | Displacement pump | 277069 | IV and V 3900 |
| 22 | Bearing housing | 287714 | IV 3900 |
| 26 | Connecting rod | 287719 | IV 3900 |
| — | Drain valve repair kit | 245103 | V 3900 |
| 34f | Inlet strainer | 181072 | All, shared with sprayers |
| — | Packing O-ring | 117285 | V 3900 |
| 34a | Suction tube | 15F149 | IV 3900 |
| — | Suction tube | 301517 | V 3900 |
| 34b | Nylon hose | 185381 | IV and V |
| 34g | Drain tube | 245731 | IV 3900 |
3. Drive, Clutch and Engine
This is the section that does not exist on an electric paint sprayer, and it is where most striper downtime originates.
A gas striper runs the engine at constant speed and engages the pump through an electric clutch. That clutch is a wear item. When the field coil or the armature wears, the clutch slips under load, and the symptom reads exactly like a tired pump: pressure that will not hold while striping, recovering when you stop.
| Ref | Component | Part | Note |
|---|---|---|---|
| 44 | Engine, gasoline 4.0 hp | 108879 | 3900 only. 5900 uses 114530 |
| 79a | Clutch coil repair kit | 287474 | IV 3900 |
| — | Clutch field repair kit | 287482 | LineLazer 3400 and GMax 3400 |
| 3 | Engine mount plate | 15F583 | V series |
| 2 | Engine mount dampener | 119695 | Supersedes 195515 |
| 93 | Pump pin | 15F855 | 3900. 5900 uses 15F856 |
| 94 | Retaining spring | 119676 | 3900 |
| 57 | Wheel repair kit | 245734 | LineLazer |
| 141 | Swivel wheel cable | 241445 | IV |
A clutch repair kit is a fraction of the cost of a displacement pump, and on a belt and clutch striper it is a more common failure than the pump. If pressure sags under load and recovers at idle, start at the clutch. We would rather sell you the cheap part that fixes it than the expensive one that does not. This is the striper equivalent of checking hydraulic oil before opening a DutyMax pump.
4. LineLazer Tips: The LL5 System
Striper tips use their own prefix but the same underlying logic as RAC X SwitchTips.
A LineLazer tip reads LL5 followed by three digits. The LL5 identifies it as a LineLazer RAC 5 SwitchTip. Then, exactly as on a paint tip, double the first digit for the line width in inches and read the last two digits as the orifice in thousandths of an inch.
| Tip | Orifice | Line width | Typical use |
|---|---|---|---|
| LL5319 | 0.019 in | ~6 in | Standard parking lot lines. Ships with the V 3900. |
| LL5421 | 0.021 in | ~8 in | Wider stalls, heavier build. Also ships with the V 3900. |
| LL5623 | 0.023 in | 8 to 12 in | Wide traffic lines, crosswalks |
Tip guard is 243161, the RAC 5 HandTite. Note that this is the RAC 5 system, not RAC X. LineLazer tips and standard airless RAC X tips are different families and do not interchange. If you also run paint sprayers, the numbering logic transfers but the hardware does not. Our spray tip size chart covers the RAC X side in full.
On a paint sprayer you notice a worn tip because the finish looks uneven. On a striper you notice it because your lines creep wider and you start using more paint per thousand feet. If your material consumption has climbed and nobody changed the pressure setting, measure a line and compare it to the tip's rated width before assuming anything else is wrong.
5. Guns, Hoses and Suction
| Component | Part | Detail |
|---|---|---|
| Flex Plus airless spray gun | 248157 | Two finger trigger, RAC 5 LineLazer |
| RAC 5 HandTite tip guard | 243161 | Holds LL5 tips |
| Whip hose, 3/8 in x 3 ft | 245797 | BlueMax II, 3,300 PSI. Replaces obsolete 245226 |
| Hose, 1/4 in x 7 ft | 245798 | Coupled |
| Hose, 3/8 in x 50 ft | 245225 | Main run, III series |
| Throat seal liquid, 4 oz | 238049 | TSL |
| Pail cover | 241005 | III series |
| Rocker switch, DPDT | 128783 | V series |
| Diffusion tube | 15C766 | V series |
The 245797 whip hose at $136.50 is worth noting specifically: it supersedes the older 245226, so if you are working from an older parts list you will be looking up a number that no longer ships.
LineLazer 3900 Parts
−8%
Graco
Graco 241445 Kit, Repair, Cable (Replaced part 114632)
Part #: 241445
$44.63
$48.30
Save $3.67
−39%
Graco
Graco 248157 Flex Plus Airless Spray Gun, 2 Finger Trigger, RAC 5 LineLazer
Part #: 248157
(1)
$240.95
$395.00
Save $154.05
−13%
Graco
Graco 245797 Airless Whip Hose Replaces part 245226
Part #: 245797
(1)
$136.50
$156.00
Save $19.50
6. Striper-Specific Fault Diagnosis
Pressure sags while striping, recovers when you stop
The machine holds pressure at idle but drops as soon as you start a long run.
Check in order: Clutch slipping under load (287474 or 287482) → inlet strainer 181072 → drain valve 245103 → pump packings. Clutch first, because it is the cheapest and the most likely on a belt driven striper.
Lines are getting wider and paint use is up
Same settings, same material, but you are covering fewer feet per pail than last season.
Cause: Worn tip. The orifice erodes and lays down a wider, heavier line. Fix: Replace the LL5 tip. Measure an actual line against the tip's rated width to confirm before ordering anything else.
Striper will not track straight
The machine pulls to one side or the front wheel wanders.
Cause: Wheel or caster wear, or a stretched swivel cable. Fix: Wheel repair kit 245734, or swivel cable 241445 on the IV. Not a fluid system problem at all, which catches people out.
Engine runs rough or vibrates badly
Noticeable new vibration through the handle, or the engine moving on its mounts.
Cause: Perished engine mount dampeners (119695, supersedes 195515). Why it matters: Vibration transmits into the drive and pump mounting and shortens the life of components well beyond the rubber mounts themselves.
Will not prime at the start of the day
Common first thing in the morning, particularly in cold weather or after storage.
Check: Inlet strainer 181072 for dried traffic paint → suction tube and gasket → drain valve seat. Traffic marking paint is harder on strainers than architectural latex and should be checked more often.
7. What Crosses Over From Sprayers
Some components genuinely cross between stripers and gas sprayers of the same generation. Others absolutely do not, and the difference is worth knowing before you raid the parts shelf.
Does cross
- Inlet strainer 181072 is specified for Ultra Max 795, 1095 and 1595 Hi-Boy, GMAX 3900 and 5900 Lo-Boy, and LineLazer 3900, 5900 and 5000.
- Clutch field repair kit 287482 fits both the GMax 3400 and the LineLazer 3400.
- Throat seal liquid, general fittings and hose by rating, as on any machine.
Does not cross
- Tips. LineLazer uses RAC 5, standard sprayers use RAC X. Different systems.
- Frames, handles, wheels and casters. Striper specific.
- Drive and pinion housings. Generation specific even within LineLazer.
- Displacement pumps across generations, which is the whole point of section 1.
The 245797 whip hose is rated to 3,300 PSI. Any replacement hose or whip on a striper must meet or exceed the machine's working pressure. Striping crews work outdoors on hard surfaces where hoses get dragged, driven over and abraded, so inspect before every shift and replace rather than repair. Material at these pressures can inject through skin, which is a surgical emergency.
8. Maintenance for a Striping Season
Striping is seasonal and front loaded, which changes the maintenance logic compared to year-round painting.
- Service before the season, not during it. Clutch, strainer, drain valve and packings all cost far less in March than they do on a job in June.
- Traffic paint is harder on strainers than architectural latex. Check 181072 daily during heavy striping rather than weekly.
- Carry spare tips in your two most used sizes. Tip wear on a striper costs you material continuously rather than failing outright.
- Keep TSL topped up. Long continuous runs mean sustained load on throat packings, which is exactly what TSL protects.
- Inspect engine mount dampeners annually. They perish quietly and take drive components with them.
- Grease the drive housing per the manual. The quantities are specified by generation, so use your own machine's manual rather than a general figure.
- Store with pump protection fluid over winter. A striper sitting idle from November to March is the classic dried-packings casualty.
Original manuals for every LineLazer generation are in our Graco manuals and technical data library, which is the fastest way to confirm which parts list applies to your model number.
Not Sure Which Generation You Have?
Send us the model number off the label and we will confirm the right parts list before you order
Ask Our Parts Team Browse LineLazer9. Frequently Asked Questions
How do I know which LineLazer 3900 generation I have?
Find the model number on the machine label rather than going by the name. LineLazer 3900 covers the III, IV and V generations, and they use different displacement pumps, drive housings and engines. The model number, not the words LineLazer 3900, is what identifies the correct parts list.
What displacement pump does the LineLazer 3900 use?
The LineLazer IV 3900 and V 3900 use displacement pump 277069. Earlier LineLazer III machines use a different fluid section. Always confirm against your machine's own parts manual, because pump assignments changed between generations even though the model name did not.
How do LineLazer tip numbers work?
LineLazer RAC 5 SwitchTips use the prefix LL5 followed by three digits. Double the first digit for the line width in inches and read the last two digits as the orifice in thousandths. LL5319 sprays roughly a 6 inch line through a 0.019 inch orifice. LL5623 sprays an 8 to 12 inch line through a 0.023 inch orifice.
Why does my line striper lose pressure mid stripe?
On a belt and clutch driven striper, check the clutch before the pump. A worn clutch field or armature slips under load, which looks exactly like pump wear but costs far less to fix. After the clutch, check the inlet strainer, then the drain valve, then the displacement pump packings.
Are LineLazer parts the same as GMAX parts?
Some are. Stripers and gas sprayers in the same generation share certain components, such as the 181072 inlet strainer and the 287482 clutch field repair kit which fits both the GMax 3400 and the LineLazer 3400. Pumps, frames and drive assemblies are striper specific. Verify by part number rather than assuming.
Striping Fleet or Municipal Contract?
Pre-season standing orders on tips, strainers and clutch kits, priced for volume
Wholesale & Fleet Pricing Call +1 713-931-4102