Caterpillarasphalt paver
Caterpillar AP-800B
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar AP-800B is a rubber-tired, mid-size asphalt paver in Cat's 8-foot-class line, built to lay mats from about 1.8 m up to a maximum 6.1 m (6 to 20 ft) wide with the right screed fitted. It carries a mechanical, Perkins-derived Cat T4.236 diesel rated around 102 gross hp (76 kW), identified by the 1BF serial prefix. Operating weight runs roughly 10,660-11,905 kg (23,500-26,240 lb) depending on whether the base tractor or a screed-equipped configuration is weighed. The AP-800B sits early in the AP-800 family: it followed the base AP-800 of the late 1980s and was itself succeeded by the AP-800C, which switched to a Cat 3054DIT turbocharged engine, and later by the AP-800D with a Cat 3054C turbo diesel rated near 130 hp. Cat offered the AP-800B with either the Extend-A-Mat 8-16B power-extending screed for variable-width work or the fixed-width Pavemaster 8B screed for simpler, lower-cost paving.
Across the AP-800 family the biggest change was engine control rather than turbocharging: the B-series kept the mechanically governed Perkins-based T4.236 (turbocharged, jerk-pump injection, no electronic controls), while the C and D generations moved to turbocharged Cat 3054-family engines with electronic engine management and more power. That mechanical simplicity is exactly why AP-800B units still hold value on the used market: no ECM, no fault codes, and few sensors to trip up a small paving crew, which keeps upkeep and diagnosis straightforward on older jobsites. Cat has since folded the whole 8-foot wheeled-paver niche into its newer AP400/455/500/555 line, so factory parts support for the AP-800B leans on remanufactured and aftermarket sources for engine, hydraulic, and screed-heat components. Contractors running these machines today value them mainly for low purchase cost and simple field repair rather than output or emissions compliance.
Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.
Caterpillar AP-800B specifications
Engine
| Engine model | Perkins T4.236, turbocharged diesel |
| Cylinders | 4, inline |
| Displacement | 3.9 L (235.6 cu in) |
| Gross power | 76 kW (102 hp) |
| Net power | not published for this configuration |
| Emissions tier | pre-Tier engine, no Cat/EPA emissions certification tier documented for this model |
Weights
| Operating weight, without screed | 10 660 kg (23,501 lb) |
| Operating weight, with standard screed | 11 902 kg (26,242 lb) |
| Ground pressure | not published |
Dimensions
| Overall length, with screed | 5.97 m (19 ft 7 in) |
| Transport width | 2.59 m (8 ft 6 in) |
| Transport height | 2.67 m (8 ft 9 in) |
| Width, hopper open | 3.30 m (10 ft 10 in) |
| Front tire size | 22 x 12 |
| Rear tire size | 16.00 x 24 |
| Auger diameter | 358 mm (14.1 in) |
| Wheelbase / ground clearance | not published |
Performance
| Maximum travel speed | 21 km/h (13 mph) |
| Maximum paving speed | 95 m/min (312 ft/min) |
| Standard paving width | 1.86 m (6 ft 1 in) |
| Maximum paving width | 6.1 m (20 ft) |
| Hopper capacity | approx. 6.9 t (7.6 tons) per factory spec sheet; treat as approximate, some listings show unit conversion issues |
| Gradeability | not published |
Service capacities (summary)
| Fuel tank | 163 L (43.1 gal) |
| Hydraulic system | 110 L (29.1 gal) |
| Cooling system | 21 L (5.5 gal) |
| Engine oil | not published |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
AP-800B fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase (with filter) - Perkins-derived T4.236 turbocharged diesel, 1BF serial prefix | approx. 9.5 L (2.5 US gal) for the Cat-installed engine with full-flow filter; the bare Perkins T4.236 base spec runs slightly lower at approx. 8.0 L (8.5 US qt) - verify against the dipstick mark on your unit, oil cooler/filter routing can shift the figure | Cat DEO (Diesel Engine Oil), API CF-4/CG-4 diesel-rated. SAE 15W-40 for general and warm-climate service; drop to SAE 10W-30 in cold climates down to about -18C (0F). Check the OMM cold-weather viscosity chart before cold starts below that range. |
| Cooling system | 20.8 L (5.5 US gal) | Cat heavy-duty antifreeze/coolant (Cat DEAC, or later-issue Cat ELC extended-life coolant where retrofitted), mixed 50/50 water-glycol, meeting Cat EC-1 spec. Add Cat SCA supplement on DEAC-filled systems per the maintenance interval schedule; ELC systems do not need SCA. |
| Fuel tank | 163.1 L (43.1 US gal) | No. 2-D diesel fuel, ASTM D975 grade. Switch to a winter-blend or No. 1-D diesel, or use an anti-gel additive, in cold-climate service to prevent fuel waxing/gelling. |
| Hydraulic system (tank plus circuit) | approx. 110.1 L (29.1 US gal) total system fill; tank-only capacity is not separately confirmed and typically runs somewhat lower than the total-system figure | Cat TDTO (Transmission/Drivetrain Oil) is the typical spec for this paver generation's hydrostatic-drive-linked hydraulic circuit - SAE 10W for cold-climate service up to SAE 30 for hot-climate service. Straight Cat HYDO hydraulic oil is an acceptable alternative on circuits that do not share hydrostatic drive-train components. Confirm against the machine's own OMM viscosity chart, as the exact hydraulic fluid call-out for this early-1990s AP-800B build could not be independently confirmed from the manual text itself. |
| Grease (all points, screed and drive-train) - spec only, no reservoir capacity | not applicable (fitting-by-fitting service, no bulk reservoir) | Cat Multipurpose Grease (MPGM), NLGI 2, lithium-complex EP grease with moly fortification for heavy-shock screed extension and drive-train grease points. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar AP-800B maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the AP-800B beyond the schedule
Predictive Maintenance & Fluid Analysis
Because the T4.236 has no ECM or onboard diagnostics, oil sampling is the main early-warning tool on the AP-800B: pull engine oil samples at every scheduled change to track wear metals from the mechanical injection pump and cylinder liners. Sample hydraulic fluid periodically too, since the open-loop gear and piston pumps driving the propel, auger, and conveyor circuits show wear through particle counts before a failure shows up as noise or slow response. Watch screed heater amperage draw as a leading indicator of failing elements.
Corrective & Common Repairs
Typical AP-800B repairs center on the mechanical drivetrain: worn tamper bar bushings and eccentric shafts causing uneven compaction, stretched auger and conveyor drive chains, and auger gearbox bearing wear from abrasive mix. The Perkins-derived fuel system commonly needs lift pump diaphragm replacement and injection pump recalibration as hours build. Screed heater elements burn out individually and need circuit-by-circuit testing rather than blanket replacement. Rubber-tired steering components, tie rods, kingpins, and wheel bearings, wear faster than on tracked pavers and should be checked whenever steering feels loose.
Overhaul & Rebuild Points
Major overhaul work on the AP-800B centers on the T4.236 top end: cylinder head, valve guides, and injection pump and nozzles should be evaluated together once compression or fuel economy drops. The hydrostatic propel pump and motor are the other big rebuild item, since they see continuous duty at paving speed. Plan wheel bearing and kingpin rebuilds on the tractor axle, and inspect the screed extension slides and crown mechanism for wear whenever the Extend-A-Mat 8-16B is stripped down for major service.
Seasonal & Environment Servicing
Cold-weather prep on the AP-800B means checking coolant strength, fitting a block heater where winter paving continues, and keeping the fuel-water separator drained since the mechanical injection pump is unforgiving of contaminated fuel. In hot weather, confirm the screed heater thermostat holds a steady mat temperature and clean the hydraulic oil cooler fins, since the mechanical engine bay traps heat around the pumps. Before storage, drain water separators, protect screed plates from corrosion, and block the machine rather than parking on flat tires.
AP-800B fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| Low Oil Pressure warning lamp (red) | Engine oil pressure has dropped below the safe minimum on the Perkins T4.236 mechanical diesel | Low oil level, worn oil pump, clogged suction screen, or failed oil pressure switch/sender | Shut engine down immediately, check oil level and check for leaks before restarting |
| High Coolant Temperature warning lamp (red) | Engine coolant temperature has exceeded the safe operating range | Low coolant level, blocked radiator core, slipping or broken fan belt, or thermostat stuck closed | Idle down, shut off if lamp stays on, check coolant level and radiator once cool |
| Alternator / Charging System warning lamp (red) | Charging circuit is not producing adequate output, battery is on discharge | Broken or slipping alternator belt, failed alternator, or loose/corroded battery connection | Check belt tension and battery terminals, test alternator output |
| Screed Heat indicator lamp (amber/green) | Shows the screed heating elements are energized; it is an on/off status light, not a fault code | Normal operation indicator, or heater circuit breaker/relay tripped if lamp will not light | Check screed heat circuit breaker and heating element wiring if lamp fails to illuminate with heat switch on |
| Hydraulic Oil Temperature gauge (red zone) | Hydraulic reservoir oil temperature has reached the high end of the analog gauge scale | Low hydraulic fluid level, clogged oil cooler, or relief valve stuck open causing excess heat | Reduce load, check fluid level and cooler fins, let system cool before continued operation |
| Low Fuel Level warning lamp | Fuel level has dropped near the reserve mark on the tank sender | Fuel running low, or faulty fuel level sender/float | Refuel and confirm sender operation if lamp stays lit after refueling |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
AP-800B attachments & work tools
Screed - Pavemaster 8B (fixed width)
Heavy-duty conventional fixed-width screed built for the 2.44 m (8 ft) paver size class the AP-800B belongs to. No power extension; base paving width is 2.44 m (8 ft). Simplest, most economical screed for mainline work with no width changes.
Screed - Extend-A-Mat 8-16B (power-extending)
Hydraulically power-extending screed for the same 2.44 m (8 ft) size class. Extends from a 2.44 m (8 ft) base out to roughly 4.9 m (16 ft) under hydraulic power; bolt-on strike-off extensions push occasional extra-wide passes further, with period listings for this paver citing paving widths up to about 6.1 m (20 ft) in full extended trim.
Bolt-on screed extensions / strike-offs
Heavy-duty screed frame on both the fixed and power-extending screed accepts bolt-on extension sections beyond the hydraulic power-extension range. Extensions mount front or rear of the main screed depending on the paving pattern, widening the mat without a full screed change.
Auger system
Twin independently controlled augers, roughly 355 mm (14 in) diameter, feed mix from the conveyor out to the screed and reverse rotation for even material distribution. Augers raise hydraulically to clear obstacles, ease trailer loading, and support the paving-width-reduction arrangement; wider auger sections pair with the wider Extend-A-Mat setup.
Conveyor and hopper
Front hopper feeds mix onto a heavy-duty steel slat conveyor running to the augers. Conveyor bed plates and chain guards are standard wear-and-guarding items sized to the conveyor, not separate optional work tools.
Screed heat and compaction elements
Screed plates are electrically heated for pre-heat before paving starts, with vibratory compaction built into the base screed deck. These functions are integral to the Pavemaster/Extend-A-Mat screed itself on this machine, not bolt-on attachments.
Screed mounting / coupling
Screed is a dedicated, size-matched unit towed behind the tractor on leveling/tow arms, connected through hydraulic quick-connects for width-extension, heat, and vibration circuits. There is no universal quick-coupler shared across unrelated tools the way loaders or excavators use one.
Hydraulic circuit notes
Screed extension, auger raise/lower, and heat/vibration functions all run off the paver's own hydraulic system rather than a separate auxiliary kit. No aftermarket hydraulic add-on is needed to run the factory screed options on this machine.
All AP-800B assemblies by section
Every catalogued assembly group for the Caterpillar AP-800B. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Basic Engine
8t7485 Actuator Gp-Linear
| 8T***85 | Actuator Group-Linear | 1 |
7c3102 Camshaft Gp
| 7C***02 | Camshaft Group | 1 |
2w7828 Cover Gp-Front Housing
| 2W***28 | Cover Group-Front Housing | 1 |
7w2534 Cover Gp-Valve Mechanism
| 7W***34 | Cover Group-Valve Mechanism | 1 |
7c8213 Crankshaft Gp
| 7C***13 | Crankshaft Group | 1 |
7c9259 Cylinder Block As-Part 1 Of 2
| 7C***59 | Cylinder Block As | 1 |
7c9259 Cylinder Block As-Part 2 Of 2
| 7C***59 | Cylinder Block As | 1 |
7c9258 Cylinder Block Gp
| 7C***58 | Cylinder Block Group | 1 |
7c3188 Cylinder Head Gp
| 7C***88 | Cylinder Head Group | 1 |
7c3750 Cylinder Head Gp
| 7C***50 | Cylinder Head Group | 1 |
7c9257 Cylinder Head Gp
| 7C***57 | Cylinder Head Group | 1 |
7c3108 Flywheel Gp
| 7C***08 | Flywheel Group | 1 |
1w7878 Gear Gp-Front
| 1W***78 | Gear Group-Front; Gear Gp-Front Idler | 1 |
8c8159 Gear-Box As
| 8C***59 | Gearbox As | 1 |
7c3103 Housing Gp-Flywheel
| 7C***03 | Housing Group-Flywheel | 1 |
7w1143 Housing Gp-Front
| 7W***43 | Housing Group-Front | 1 |
7w2537 Lifting Eye Gp-Engine
| 7W***37 | Lifting Group-Engine; Lifting Eye Gp-Engine | 1 |
7c3116 Mounting Gp-Engine
| 7C***16 | Mounting Group-Engine | 1 |
7c3104 Pan Gp-Engine Oil
| 7C***04 | Pan Group-Oil; Pan Gp-Engine Oil | 1 |
7w2511 Rod & Piston Gp
| 7W***11 | Piston & Rod Group; Rod & Piston Gp | 1 |
7x9024 Power Pack As-Part 1 Of 6
| 7X***24 | Power Pack As | 1 |
7x9024 Power Pack As-Part 5 Of 6
| 7X***24 | Power Pack As | 1 |
7x9024 Power Pack As-Part 2 Of 6
| 7X***24 | Power Pack As | 1 |
7x9024 Power Pack As-Part 4 Of 6
| 7X***24 | Power Pack As | 1 |
7x9024 Power Pack As-Part 6 Of 6
| 7X***24 | Power Pack As | 1 |
7x9024 Power Pack As-Part 3 Of 6
| 7X***24 | Power Pack As | 1 |
7c8209 Pulley Gp-Crankshaft
| 7C***09 | Pulley Group-Crankshaft | 1 |
7w2531 Valve Mechanism Gp
| 7W***31 | Valve Mechanism Group | 1 |
Brakes
819511 Brake System-Foot
| 08***11 | Brake As-Foot | 1 |
8c7455 Brake Gp
| 8C***55 | Brake Group | 1 |
7x9945 Brake Gp
| 4L***37 | Hex Head Capscrew, 3/8 Nc X 1 1/2 In. (38 mm) | 8 |
| 6V***01 | Nut; (3/8-16-Thd)(Plate To Rh And Lh Bracket As) | 8 |
| 7X***78 | Valve Group-Brake | 2 |
7x9378 Valve Gp-Brake
| 7X***78 | Valve Group-Brake | 1 |
Console/Panel
7x9019 Console As-Part 1 Of 2
| 7X***19 | Console As | 1 |
7x9019 Console As-Part 2 Of 2
| 7X***19 | Console As | 1 |
819769 Panel As-Instrument
| 08***69 | Panel As-Instrument | 1 |
822614 Panel As-Instrument
| 08***14 | Panel As-Instrument | 1 |
8c7633 Steering As
| 8C***33 | Steering As | 1 |
Cooling System
7c9264 Cooler & Filter Gp-Engine Oil
| 7C***64 | Cooler & Filter Group-Engine Oil | 1 |
7c9264 Cooler & Filter Gp-Engin Oil
| 7C***64 | Cooler & Filter Group-Engine Oil | 1 |
7w2608 Fan Gp
| 7W***08 | Fan Group | 1 |
7x9972 Lines As-Oil Cooler
| 7X***72 | Lines As-Oil Cooler | 1 |
7c3112 Lines Gp-Water
| 7C***12 | Lines Group-Water; Lines Gp-Engine Water | 1 |
7c3111 Pump Gp-Water
| 7C***11 | Pump Group-Water | 1 |
4w7684 Pump Gp-Water
| 4W***84 | Pump Group-Water | 1 |
Engine Arrangement
7c9250 Engine Ar-Part 2 Of 2
| 7C***04 | Pan Group-Oil; Pan Gp-Engine Oil | 1 |
| 7C***06 | Pump Group-Engine Oil | 1 |
| 7C***07 | Pump Group-Fuel Injection | 1 |
7c9250 Engine Ar-Part 1 Of 2
| 1W***78 | Gear Group-Front; Gear Gp-Front Idler | 1 |
| 1W***10 | Lines Group-Fuel Filter | 1 |
| 2W***28 | Cover Group-Front Housing | 1 |
Feeder And Screw Conveyor
8c3924 Chain As-Drag
| 8C***24 | Chain As-Drag | 1 |
7x8245 Chain As-Drag
| 7X***45 | Chain As-Drag | 1 |
7x9021 Conveyor As
| 7X***21 | Conveyor As | 1 |
819552 Conveyor As-Drag
| 08***52 | Conveyor As-Drag | 1 |
819555 Conveyor As-Screw
| 08***55 | Conveyor As-Screw | 1 |
819513 Gate System-Drag Conveyor
| 08***13 | Gate System-Drag Conveyor | 1 |
8c8160 Torque Hub As
| 8C***60 | Hub As-Torque | 1 |
7r4243 Kit-Grease Line
| 09***99 | Fitting-Grease; (Hydraulic) | 2 |
| 4D***59 | Boss | 2 |
| 4S***99 | Str. Connector, 1/4in. J.I.C. X 1/4in. N.P.T. | 2 |
7r4244 Kit-Seal
| 2H***64 | Bolt-Hex Socket Head; (1/4-20x1.5in) | 4 |
| 6V***35 | Setscrew-Socket; (7/16-20x0.375-In) | 4 |
| 7R***77 | Collar | 2 |
7x9961 Lubrication System-Drag Convey0r
| 7X***61 | Lubrication Group | 1 |
7r4048 Lubrication Gp-Front Bearing
| 7R***48 | Lubrication Group-Front Bearing | 1 |
822575 Motor Gp-Hydraulic
| 08***75 | Motor Group-Hydraulic | 1 |
817761 Sensor Gp-Feed
| 08***61 | Sensor Group-Feed | 1 |
Frame
8c8001 Cylinder As-Hydraulic
| 8C***01 | Cylinder As-Hydraulic | 1 |
8c8000 Cylinder As-Hydraulic
| 8C***00 | Cylinder As-Hydraulic | 1 |
819507 Main-Frame As-Part 2 Of 2
| 08***07 | Frame As-Main | 1 |
819507 Main-Frame As-Part 1 Of 2
| 08***07 | Frame As-Main | 1 |
819512 Hopper As
| 08***12 | Hopper As | 1 |
819510 Plate As-Upper Deck Cover
| 08***10 | Plate As-Upper Deck Cover | 1 |
8c7457 Roller Ar-Push-(Oscillating)
| 8C***57 | Roller Ar-Push | 1 |
8c3948 Roller As-Push
| 8C***48 | Roller As-Push | 1 |
1c4717 Roller As-Push-Part 1 Of 2
| 1C***17 | Roller As-Push | 1 |
1c4717 Roller As-Push-Part 2 Of 2
| 1C***17 | Roller As-Push | 1 |
8c4339 Roller Gp-Push (8'6")
| 8C***39 | Roller Group-Push | 1 |
6r2241 Roller Gp-Push
| 6R***41 | Roller Group-Push | 1 |
5e9822 Roller Gp-Push
| 5E***22 | Roller Group-Push | 1 |
819636 Ski As-Traveling
| 08***36 | Ski As-Traveling | 1 |
8c7158 Ski Expansion Gp
| 8C***58 | Ski Expansion Group | 1 |
7x9960 Support As-Tow Arm
| 7X***60 | Support As-Tow Arm | 1 |
819515 Support As-Tow Arm
| 08***15 | Support As-Tow Arm | 1 |
Fuel System And Governor
7c3115 Filter Gp-Fuel
| 7C***15 | Filter Group-Fuel | 1 |
7x9985 Fuel System
| 7X***85 | Fuel Ar-Diesel | 1 |
1w8310 Lines Gp-Fuel Filter
| 1W***10 | Lines Group-Fuel Filter | 1 |
7w2588 Lines Gp-Fuel Injection
| 7W***88 | Lines Group-Fuel Injection | 1 |
8c7624 Pump As-Motor
| 8C***24 | Pump As | 1 |
7n6422 Pump Gp-Fuel
| 7N***22 | Pump Group-Fuel | 1 |
7c3139 Pump Gp-Fuel Injection
| 7C***39 | Pump Group-Fuel Injection | 1 |
7c3107 Pump Gp-Fuel Injection
| 7C***07 | Pump Group-Fuel Injection | 1 |
Hydraulic System
822340 Tow Arm Gp-Part 1 Of 2
| 08***40 | Arm Group-Tow; Tow Arm Gp | 1 |
822340 Tow Arm Gp-Part 2 Of 2
| 08***40 | Arm Group-Tow; Tow Arm Gp | 1 |
822343 Tow Arm Gp
| 08***43 | Arm Group-Tow; Tow Arm Gp-10'Fixed Screed | 1 |
822343 Tow Arm Gp-10 Ft. Vip
| 08***43 | Arm Group-Tow; Tow Arm Gp-10'Fixed Screed | 1 |
7r2768 Box As-Control
| 7R***68 | Box As-Control | 1 |
7r2802 Brace Gp
| 7R***02 | Brace Group | 1 |
7x9160 Burner Gp-8' Screed
| 7X***60 | Burner Group-Screed; Burner Gp-8' Screed | 1 |
7x8691 Control Gp-Crowning
| 7X***91 | Control Group-Crowning-Screed | 1 |
7x8699 Control Gp-Thickness
| 7X***99 | Control Group-Screed; Control Gp-Screed-Thickness | 1 |
8c4338 Control Gp-Tow Point
| 8C***38 | Control Group-Tow Point | 1 |
822605 Control Gp-8'Vip Screed
| 08***05 | Control Group-Vip Screed; Control Gp-8' Vip Screed | 1 |
822608 Control Gp-10' Vip Screed
| 08***08 | Control Group-Vip Screed; Control Gp-10' Vip Screed | 1 |
8c7454 Counterbalance Gp-Screed
| 8C***54 | Counterbalance Group-Screed | 1 |
5e9402 Covers Gp-10' Screed
| 5E***02 | Cover Group-Screed; Covers Gp-10' Screed | 1 |
8c7166 Cylinder Gp-Hydraulic
| 8C***66 | Cylinder Group-Hydraulic | 1 |
7x9161 Electrical Gp
| 08***12 | Junction Box As-Screed | 1 |
| 7R***68 | Box As-Control | 2 |
| 7X***61 | Electrical Group | 1 |
7x9162 Extension Gp-1'
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 10 |
| 7X***34 | Bolt-Plt; (1/2unc X 5) | 4 |
| 7X***62 | Extension Group-1' | 1 |
7x8967 Extension Gp-1 In. Screed-Vip-Lh
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 3 |
| 7X***67 | Extension Group-1' Lh Vip | 1 |
| 7X***70 | Extension Group-Auger | 1 |
7x8966 Extension Gp
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 3 |
| 7X***66 | Extension Group-1' Rh Vip | 1 |
| 7X***71 | Extension Group-Auger | 1 |
7x8856 Extension Gp-Vip-Lh
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 3 |
| 7X***56 | Extension Group-2' Lh Vip | 1 |
| 7X***58 | Extension Group-Screed; -Lh | 1 |
7x8857 Screed Gp-Extension
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 3 |
| 7X***57 | Extension Group-2' Rh Vip | 1 |
| 7X***59 | Extension Group-Screed; -Rh | 1 |
7x8970 Extension Gp-Auger
| 7X***70 | Extension Group-Auger | 1 |
7x8886 Extension Gp-Auger
| 7X***86 | Extension Group-Auger | 1 |
7x8885 Extension Gp-Auger
| 7X***85 | Extension Group-Auger | 1 |
7x8971 Extension Gp-Auger
| 7X***71 | Extension Group-Auger | 1 |
7x9165 Extension Gp-Lh
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 3 |
| 7X***70 | Extension Group-Auger | 1 |
| 7X***65 | Extension Group-Lh | 1 |
7x9164 Extension Gp-Rh 1'
| 6V***88 | Nut-Full (1/2-13 Thd); (1/2-13-Thd)(Full) | 3 |
| 7X***71 | Extension Group-Auger | 1 |
| 7X***64 | Extension Group-Rh; Extension Gp-Rh 1' | 1 |
7x8858 Extension Gp-Screed-2 Ft. 4 In
| 7X***58 | Extension Group-Screed; -Lh | 1 |
7x8859 Extension Gp-Screed
| 7X***59 | Extension Group-Screed; -Rh | 1 |
7x9182 Extension Gp-Screed
| 7X***82 | Extension Group-Screed; -Rh | 1 |
7x9183 Extension Gp-Screed-Vip-L.H.
| 7X***83 | Extension Group-Screed; -Lh | 1 |
7x9163 Finish Gp-Vip
| 7X***63 | Finish Group-Vip | 1 |
7x8684 Frame Gp-Screed
| 7X***84 | Frame Group-Screed; Frame Gp-Screed-Pavemaster | 1 |
7x8690 Endgate Gp
| 7X***90 | Gate Group-Screed End | 1 |
7x8693 Handrail Gp-Screed
| 7X***93 | Handhold Group-Screed; Handrail Gp-Screed | 1 |
822612 Junction Box As-Screed
| 08***12 | Junction Box As-Screed | 1 |
6r1367 Kit-Shift
| 6R***67 | Kit-Shift | 1 |
7x9977 Lines As-Conveyor/Auger Drive
| 7X***77 | Lines As-Auger/Conveyor Drive | 1 |
7x9978 Lines As-Conveyor/Auger Drive
| 7X***78 | Lines As-Auger/Conveyor Drive | 1 |
7x9982 Lines As-Brakes & Steering
| 7X***82 | Lines As-Brakes & Steering | 1 |
7x9976 Lines As-Hopper Raise
| 7X***76 | Lines As-Hopper Raise | 1 |
7x9983 Lines As-Hydraulic Brake Press
| 7X***83 | Lines As-Hydraulic Brake Press | 1 |
7x9975 Lines As-Hydraulic Steering
| 7X***75 | Lines As-Hydraulic Steering | 1 |
7x9980 Lines As-Screed Lift
| 7X***80 | Lines As-Screed Lift | 1 |
7x9974 Lines As-Steering & Screed Pressure
| 7X***74 | Lines As-Steer & Screed Press | 1 |
7x9971 Lines As-Suction
| 7X***71 | Lines As-Suction | 1 |
7x9986 Lines As-Transmission Shift
| 7X***86 | Lines As-Transmission Shift | 1 |
7x9981 Lines As-Truck Hitch
| 7X***81 | Lines As-Truck Hitch | 1 |
7x9979 Lines As-Vibrator Drive
| 7X***79 | Lines As-Vibrator Drive | 1 |
7x9973 Lines As-Wheel Drive
| 7X***73 | Lines As-Wheel Drive | 1 |
7x8962 Burner Gp-10' Screed
| 7X***62 | Lines Group-Fuel; Burner Gp-10' Screed | 1 |
7r6357 Fuel Gp-10' Fixed Screed
| 7R***57 | Lines Group-Fuel | 1 |
8c7616 Pump Gp-Auger-Conveyor Drive-Part 2 Of 2
| 8C***16 | Pump Group | 1 |
8c7989 Pump Gp-Hydraulic*R
| 8C***89 | Pump Group | 1 |
8c7616 Pump Gp-Auger-Conveyor Drive-Part 1 Of 2
| 8C***16 | Pump Group | 1 |
8c7987 Pump Gp-Auxiliary Drive*R
| 8C***87 | Pump Group | 1 |
7x9158 Screed Ar
| 08***07 | Vibrator Group-Screed; Vibrator Gp-10' Screed | 1 |
| 08***08 | Control Group-Vip Screed; Control Gp-10' Vip Screed | 1 |
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x9157 Screed Ar
| 08***04 | Vibrator Group-Screed | 1 |
| 08***05 | Control Group-Vip Screed; Control Gp-8' Vip Screed | 1 |
| 7X***57 | Screed Ar; Screed Ar-8' Vip | 1 |
7r0339 Screed Ar-10'
| 5E***00 | Vibrator Group-Screed; Vibrator Gp-10' Screed | 1 |
| 5E***02 | Cover Group-Screed; Covers Gp-10' Screed | 1 |
| 7R***39 | Screed Ar-10' Fixed | 1 |
8c3954 Screed Ar
| 08***43 | Arm Group-Tow; Tow Arm Gp-10'Fixed Screed | 1 |
| 7R***39 | Screed Ar-10' Fixed | 1 |
| 7X***62 | Extension Group-1' | 1 |
8c4335 Screed Ar-10' Vip
| 08***43 | Arm Group-Tow; Tow Arm Gp-10'Fixed Screed | 1 |
| 7X***58 | Screed Ar; Screed Ar 10' Vip | 1 |
| 7X***62 | Extension Group-1' | 1 |
8c3950 Screed Ar-8' Vip
| 08***40 | Arm Group-Tow; Tow Arm Gp | 1 |
| 7X***57 | Screed Ar; Screed Ar-8' Vip | 1 |
| 7X***62 | Extension Group-1' | 1 |
7x8689 Strike-Off Gp-10' Screed
| 7X***89 | Strike-Off Group-Screed; Strike-Off Gp-10' Screed | 1 |
7x8961 Structural Gp-10'-Vip-Part 3 Of 6
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x8961 Structural Gp-10'-Vip-Part 1 Of 6
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x8961 Structural Gp-10'-Vip-Part 2 Of 6
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x8961 Structural Gp-10'Vip Screed-Part 6 Of 6
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x8961 Structural Gp-10'-Vip Screed-Part 5 Of 6
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x8961 Structural Gp-10'-Vip-Part 4 Of 6
| 7X***61 | Structural Group; Structural Gp-10' Vip | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 3 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 6 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 4 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 7 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 2 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 1 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
7x9159 Structural Gp-8' Vip Screed-Part 5 Of 7
| 7X***59 | Structural Group-Screed; Structural Gp-8' Vip Screed | 1 |
819514 Tank As-Hydraulic Oil
| 08***14 | Tank As-Hydraulic | 1 |
7x8208 Valve Bank As-2 Valve
| 7X***08 | Valve As | 1 |
822586 Valve As-Divided Flow
| 08***86 | Valve As-Flow Divider | 1 |
822607 Vibrator Gp-Screed-10 Ft. Vip
| 08***07 | Vibrator Group-Screed; Vibrator Gp-10' Screed | 1 |
822604 Vibrator Gp-Screed
| 08***04 | Vibrator Group-Screed | 1 |
5e9400 Vibrator Gp-10' Screed
| 5E***00 | Vibrator Group-Screed; Vibrator Gp-10' Screed | 1 |
Intake And Exhaust System
7w2565 Manifold Gp-Exhaust
| 7W***65 | Manifold Group-Exhaust | 1 |
7w2585 Manifold Gp-Inlet
| 7W***85 | Manifold Group-Inlet | 1 |
7w2573 Turbocharger Gp
| 7W***73 | Turbocharger Group | 1 |
7w2584 Turbocharger Gp
| 7W***84 | Turbocharger Group | 1 |
Lubrication System
7c3110 Fumes Disposal Gp
| 7C***10 | Fumes Disposal Group | 1 |
7c3105 Gauge Gp-Oil Level (Dipstick)
| 7C***05 | Gauge Group-Oil Level (Dipstick) | 1 |
7c3106 Pump Gp-Engine Oil
| 7C***06 | Pump Group-Engine Oil | 1 |
Power Train
817050 Differential As-Part 5 Of 5
| 08***50 | Axle Group-Drive | 1 |
817050 Differential As-Part 4 Of 5
| 08***50 | Axle Group-Drive | 1 |
817050 Differential As-Part 2 Of 5
| 08***50 | Axle Group-Drive | 1 |
817050 Differential As-Part 3 Of 5
| 08***50 | Axle Group-Drive | 1 |
817050 Differential As-Part 1 Of 5
| 08***50 | Axle Group-Drive | 1 |
8c8009 Cylinder Gp-Hydraulic
| 8C***09 | Cylinder Group-Hydraulic | 1 |
5e8835 Kit-Differential Cooling
| 5E***35 | Kit-Differential Cooling | 1 |
819508 Transmission & Axle As
| 08***08 | Transmission & Axle As | 1 |
Service Equipment And Supplies
819642 Decal As
| 08***00 | Decal-Cooling System | 1 |
| 08***93 | Decal-Diesel Fuel | 1 |
| 08***94 | Decal-Hydraulic Fluid | 1 |
9n7049 Hose Gp-Spraydown
| 9N***49 | Hose Group-Spraydown | 1 |
Slope And Grade Control
8c2975 Control Ar-Primary Grade
| 8C***75 | Control Ar-Primary Grade | 1 |
7x9987 Control As-Automatic Grade
| 7X***87 | Control As-Automatic Grade | 1 |
8c2974 Control As-Slope
| 8C***74 | Control As-Slope | 1 |
5e9807 Control Gp-Automatic Grade
| 5E***07 | Control Group-Automatic Grade | 1 |
8c2976 Controller As
| 8C***76 | Controller As-Single Grade | 1 |
8t8029 Controller Gp
| 8T***29 | Controller Group | 1 |
8c7159 Stringline Ar-Traveling
| 8C***59 | Stringline Ar-Traveling | 1 |
817214 Stringline As-Traveling
| 08***14 | Stringline As-Traveling | 1 |
9n8911 Stringline As-Traveling
| 9N***11 | Stringline As-Traveling | 1 |
Starting And Electrical System
6t1194 Alternator Gp-Part 1 Of 2
| 6T***94 | Alternator Group-Charging | 1 |
6t1194 Alternator Gp-Part 2 Of 2
| 6T***94 | Alternator Group-Charging | 1 |
6r3285 Beacon Gp
| 6R***85 | Beacon Group | 1 |
7x9969 Console As-Left Control
| 7X***69 | Console As-Control-Lh | 1 |
819768 Console As-Left Control
| 08***68 | Console As-Control-Lh | 1 |
819770 Console As-Right Control
| 08***70 | Console As-Control-Rh | 1 |
7x9970 Console As-Right Control
| 7X***70 | Console As-Control-Rh | 1 |
6r0699 Control Gp-Electrical
| 6R***99 | Control Group-Conv/Auger Pump Dr | 1 |
7x9016 Electrical As
| 7X***16 | Electrical As | 1 |
5e4869 Electrical As
| 5E***69 | Electrical As | 1 |
7x9967 Junction Box As-Main
| 7X***67 | Junction Box As-Main | 1 |
5e4870 Junction Box As-Main
| 5E***70 | Junction Box As-Main | 1 |
7r3075 Kit-Valve
| 7R***75 | Kit-Valve | 1 |
7r3076 Kit-Valve
| 7R***76 | Kit-Valve | 1 |
7t0618 Lamp Gp
| 7T***18 | Lamp Group | 1 |
7c9252 Mounting Gp-Alternator
| 7C***52 | Mounting Group-Alternator | 1 |
7c9269 Mounting Gp-Starting Motor-(Electric)
| 7C***69 | Mounting Group-Starting Motor; Mounting Gp- Starting Motor | 1 |
8c8278 Solenoid As
| 8C***78 | Solenoid As | 1 |
7w2606 Starting Aid Gp
| 7W***06 | Starting Aid Group | 1 |
9n7775 Valve As-Solenoid
| 9N***75 | Valve As-Solenoid | 1 |
Steering
7x9965 Bogie As-L.H.
| 7X***65 | Bogie As-Lh | 1 |
7x9966 Bogie As-R.H.
| 7X***66 | Bogie As-Rh | 1 |
8c8002 Cylinder As-Hydraulic
| 8C***02 | Cylinder As-Hydraulic; (Hydraulic) | 1 |
6r1368 Kit-Steering
| 6R***68 | Kit-Steering | 1 |
7x9964 Spindle & Hub As
| 7X***64 | Spindle & Hub As | 1 |
7x9963 Suspension As-Front
| 7X***63 | Suspension As-Front | 1 |
7r0197 Valve Gp-Steering
| 7R***97 | Valve Group-Steering; -Steering | 1 |
7x9962 Tires & Wheels As-Rear
| 7X***62 | Wheel & Tire As-Rear | 1 |
AP-800B serial number reference
The PIN plate on an AP-800B sits on the frame near the operator's station, usually on the right-hand console upright or tractor frame rail below the seat platform; some units repeat it on the engine side panel. Read the first 3 characters as the prefix (here 1BF) identifying the model/engine build series, followed by the sequential unit number - compare the full PIN against the machine's parts or service manual coverage range to confirm which build phase (base AP-800 vs AP-800B) it falls into.
| Prefix | Identifies | Notes |
|---|---|---|
| 1BF | AP-800B (and base AP-800), Perkins T4.236 engine | Base AP-800 documentation covers 1BF00001 through 1BF00224. AP-800B production picks up the same prefix from 1BF00225-up, same Perkins T4.236 (4.236) engine family. One continuous prefix range shared across the base and B-suffix update rather than a separate code. |
Frequently asked questions
What engine does the Caterpillar AP-800B use?
The AP-800B runs a turbocharged, mechanically governed Perkins-derived Cat T4.236 diesel rated around 102 gross hp (76 kW), identified by the 1BF serial prefix. It has no electronic engine controls (no ECM), unlike the later Cat 3054-family engines fitted to the AP-800C and AP-800D, which added electronic engine management.
What is the operating weight of the AP-800B?
Operating weight runs roughly 10,660-11,905 kg (23,500-26,240 lb), varying with whether the base tractor or a screed-equipped configuration is measured. Exact figures vary by screed and options fitted, so check your machine's data plate for the specific configuration.
What replaced the Caterpillar AP-800B?
There is no single direct successor. Within its own family the AP-800B was followed by the turbocharged AP-800C and AP-800D, and Cat eventually discontinued the whole AP-800 line, folding the 8-foot wheeled-paver niche into its current AP400/455/500/555 series. There is no one-for-one replacement model to point to.
What AP-800B owners discuss
What do operators say about the AP-800B's powertrain overall?
It's regarded as mechanically simple compared to later electronic pavers. The turbocharged Perkins-derived T4.236 diesel (about 76 kW / 102 hp) drives the hydraulic pumps directly with no engine ECM and no self-diagnostics on the propel or feeder circuits. The tradeoff owners mention is that troubleshooting is manual: a sluggish or uneven wheel speed side-to-side usually traces back to worn hydraulic pumps, a restricted filter, or low system pressure rather than a fault code, since there isn't one to read. Have your dealer verify hydraulic pump output pressure before condemning a pump.
What engine problems come up most often on the T4.236 in this paver?
Cooling and turbo oiling are the recurring complaints across owners of this engine family. Blocked water galleries create hot spots that lead to head gasket failure, and white smoke on startup is the classic tell for a leaking gasket or cracked head. Turbo failures are most often traced back to oil starvation at the turbo bearing rather than a bad turbo out of the box, so low oil supply pressure is worth checking before condemning the turbocharger itself. Water pumps and injection pump/injector components tend to need attention on roughly the same long-interval timeline as the head gasket over a full service life. Have your dealer verify head gasket condition and turbo oil-feed pressure on any unit with unknown history.
What wears out fastest on the feeder and auger system?
The feeder system takes the brunt of hot, abrasive mix contact: floor plates, auger flights, conveyor chains, and flight bars. Auger flights lose their square edge and go pointed as they wear, dropping in effective diameter and moving material less consistently, which shows up as streaking in the mat. Floor plates thin out and warp, conveyor chains sag, and worn flight bars let mix pack in underneath. Bearing seals that go bad let abrasive mix into the bearings themselves. With attentive maintenance these components commonly run 7,000+ hours, but mix composition (rock type and fines content) swings that figure a lot, so treat it as a range, not a guarantee.
Is there a common complaint about screed alignment or tow points?
Yes, this is one of the most repeated screed complaints on wheeled pavers of this type generally. Slop accumulates at the tow point pivots and bushings over time, and even a small amount of play at each pivot adds up to visible mat-thickness variation side-to-side. Worn depth-crank threads let the screed creep on its own without operator input. The common field check is pulling a string line or straight edge across the screed periodically to catch alignment drift early, and rebuilding lift cylinder seals/packing once lift response goes uneven side-to-side.
What electrical or sensor issues show up on these older pavers?
The AP-800B predates electronic engine and propel diagnostics, so most electrical complaints center on the screed heater circuit and on any aftermarket grade or material-feed sensors added after the fact. Corrosion and loose terminals at the heating element connections are the most common heater-circuit fault, and a tripped circuit breaker usually points to a shorted element or damaged harness rather than the breaker itself. For aftermarket feed and slope sensors, daily cleaning matters: wiping the sensor face at shutdown while it's still warm keeps stray mix from throwing off readings on the next shift.
What should a buyer check before purchasing a used AP-800B?
Measure screed plate thickness at all four corners: new is roughly 12.7 mm (0.5 in), and around 6.4 mm (0.25 in) remaining still has usable life, but a side-to-side thickness mismatch signals the machine was run out of alignment. This is a wheeled paver, not tracked, so check drive tire wear and sidewall condition on both the front and rear axles. Grab the auger by hand and check for play at the bearings and mounting; looseness means bearing replacement is coming due. Look for oil weeping at the engine and hydraulic pump seals, and run the machine to listen for abnormal turbo or water pump noise. Weigh hour totals against visible wear, since feeder components in the 7,000+ hour range are approaching end of service life. Have your dealer verify engine compression and hydraulic pump flow before final purchase.
How does the AP-800B's hydraulic propel system compare to later pavers in day-to-day operation?
Owners describe the propel and feeder hydraulics as durable but unforgiving of deferred maintenance, since there's no onboard diagnostics to flag a developing problem early the way later electronic-control pavers do. Response can vary by how the machine was optioned from the factory and by hours on the pumps and motors, so treat any specific complaint about slow or jerky propel response as configuration- and wear-dependent rather than a universal trait. Regular filter changes and keeping hydraulic oil clean are cited repeatedly as the main preventive measure owners rely on to avoid pump and motor wear on this generation of machine.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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