Powerhorse M46851C User manual

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Gasoline Stationary Air Compressor
Installation, Operation and Maintenance Manual
To the Owner:
Thank you for purchasing a Powerhorse Air Compressor. Your machine is designed for long life,
dependability, and the top performance you demand! Please take time now to read through this manual so you
better understand the machine’s operation, maintenance and safety precautions. Everyone who operates this
machine must read and understand this manual. The time you take now will prolong your machine’s life and
prepare you for its safe operation. Enjoy the exceptional performance of your Powerhorse Air Compressor, the
industry leader!
The manufacturer reserves the right to make improvements in design and/or changes in specifications at any
time without incurring any obligation to install them on units previously sold.
Quick Facts
Engine Oil Engine is shipped without oil. Fill before starting.
Use SAE 10W-30 motor oil.
Pump Oil
Check pump oil level before starting. Use SAE 30W non-detergent pump oil (part # 4043).
Air Filter Replacement air filter part number is #35409.
Maximum
Pressure Item #46851 maximum pressure = 175 psi
Maintenance
Schedule Engine: Oil: change after first 20 hours, then annually or every 100 hours. Spark Plug: clean every 100 hrs., replace annually or every 300 hrs.
Air Filter: clean weekly, replace annually or every 1000 hrs.
Refer to your Powerhorse engine owner’s manual for further
instructions.
Tank: Drain water daily.
Compressor
Pump: Oil: change after first 50 hours, then every 3 months or 500 hours.
Read and understand all manuals before operating.
Any Questions, Comments, Problems or Parts Orders
Call Powerhorse Product Support 1-866-443-2576
46851; 414cc Powerhorse Engine,
30 Gal. Stationary M46851C

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Table of Contents
Important Safety Instructions 2 Maintenance 6
Receipt and Inspection 2 Kits & Service Parts 6
Machine Component
Identification 3 Exploded View / Component List 7-8
Assembly 4 Pneumatic Schematic Diagrams 9
Operation 5 Troubleshooting 10
Limited Warranty 11
Safety
DEFINITIONS DANGER!
WILL cause DEATH, SEVERE INJURY or substantial
property damage. WARNING!
CAN cause DEATH, SEVERE INJURY or substantial
property damage. CAUTION!
WILL or CAN cause MINOR INJURY or property
damage.
GENERAL SAFETY PRECAUTIONS
ALWAYS wear eye protection when operating or
servicing compressor.
NEVER operate where flammable or explosive liquids or
vapors such as gasoline, natural gas and solvents are
present.
NEVER remove, paint over, or deface decals. Replace
any missing decals.
NEVER operate with guards or shields removed,
damaged or broken.
NEVER operate indoors. This compressor is intended
for outdoor use only. Avoid inhaling exhaust fumes, risk
of asphyxiation. Exhaust fumes are deadly.
NEVER add fuel when the product is operating or hot.
NEVER directly inhale compressed air.
NEVER over-pressurize the receiver tank or similar
vessels beyond design limits.
NEVER use a receiver tank or similar vessels that fail to
meet the design requirements of the compressor.
NEVER drill into, weld or otherwise alter the receiver
tank or similar vessels.
NEVER remove, adjust, bypass, change, modify or
make substitutions for safety/relief valves, unloader
valve or other pressure control related devices.
NEVER use air tools or attachments without first
determining the maximum pressure recommended for
that equipment.
NEVER point air nozzles or sprayers toward people or
animals.
NEVER touch the compressor pump, engine or
discharge tubing during or shortly after operation. These
parts become hot.
BREATHING AIR PRECAUTION
Powerhorse air compressors are not designed,
intended or approved for breathing air. Compressed air
should not be used for breathing air applications unless
treated in accordance with all applicable codes and
regulations.
Receipt and Inspection
Before signing the delivery receipt, inspect for
damage and missing parts. If damage or missing parts
are apparent, make the appropriate notation on the
delivery receipt, then sign the receipt. Immediately
contact the carrier for an inspection. All material must be
held in the receiving location for the carrier’s inspection.
Delivery receipts that have been signed without a
notation of damage or missing parts are considered to
be delivered “clear.” Subsequent claims are then
considered to be concealed damage claims. Settle
damage claims directly with the transportation company.
If you discover damage after receiving the air
compressor (concealed damage), the carrier must be
notified within 15 days of receipt and an inspection must
be requested by telephone with confirmation in writing.
On concealed damage claims, the burden of
establishing that the compressor was damaged in transit
reverts back to the claimant.
Read the compressor nameplate to verify it is the
model ordered, and read the motor nameplate to verify it
is compatible with your electrical conditions. Make sure
electrical enclosures and components are appropriate.

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Machine Component Identification
1. Engine Control - Location of choke, engine speed and fuel valve.
2. Engine - Engine is NOT shipped with oil. Refer to engine owners’ manual for proper viscosity and capacity
of oil for your engine.
3. Start Switch - Make sure switch is at “ON” position, push the start switch to crank engine.
4. On/Off Switch - Make sure switch is at “ON” position when starting engine with the recoil.
5. Ball Valve - 3/4” NPT.
6. Pressure Gauge - Easy to read liquid filled gauge.
7. ASME Safety Valve - This valve automatically releases air if the tank pressure exceeds the preset
maximum.
8. Air Receiver - 30 gallon ASME certified tank.
9. Pump Oil Drain – Drain the pump oil from this plug.
10. Lifting Eyes - Also use as tie down locations.
11. Discharge Tube - This tube carries compressed air from the pump to the check valve. This tube
becomes very hot during use. To avoid the risk of severe burns, never touch the discharge tube.
12. Drain Valve - Location of tank drain valve. Drain tank daily after each use.
13. Unloader - Lift knob to relieve pressure when starting the engine.
14. Air Compressor Pump - Air compressor pump is shipped with oil. Remove shipping plug and replace with
oil fill plug in manual bag.
15. Belt Guard - Covers the belt, motor pulley and flywheel. NEVER operate compressor without belt guard.
16. Compressor Air Filter - Make sure your air filter is clean and particle free. See pump exploded view for
replacement filter part number.

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Installation
SELECTING A LOCATION
Select a well-lit area with plenty of space for proper cooling airflow and accessibility. Locate the compressor at
least 15 inches (38 cm) from walls.
Temperature. Ideal operating temperatures are between 40°and 100°F (4°and 37°C). If temperatures
consistently drop below 32°F (0°C), you must protect safety/relief valves and drain valves from freezing.
CAUTION!
NEVER operate in temperatures below 15°F (-9°C) or above 125°F (52°C).
Humid Areas. In frequently humid areas, moisture may form in the pump and produce sludge in the lubricant,
causing running parts to wear out prematurely. Excessive moisture is especially likely to occur if the compressor is
located in an unheated area that is subject to large temperature changes.
Step 1. Mounting Dimensions
Step 2. Connecting a Battery
Your air compressors engine is equipped with an electric starter, which requires the installation of a 12-volt
battery. The battery is to be supplied by the customer. Follow the instructions detailed below for connecting
and disconnecting the battery.
WARNING: Battery hazards
Batteries are hazardous because they contain caustic acid, can emit explosive gases, and can
cause electric shock. Caution must be exercised when making connections to a battery to
avoid shock and contact with the acid, and to prevent any sparking that could lead to an
explosion.
ALWAYS follow the general battery safety rules and instructions listed below.
General Battery
Safety Rules •ALWAYS use eye protection when handling batteries.
•NEVER smoke or work near sparks or other sources of ignition.
•NEVER touch both battery terminals at the same time with your hand or any non-
insulated tools.
•If battery acid contacts skin or clothing, flush immediately with water and neutralize
with baking soda.
Connecting the
battery Always connect the cables in the following sequence to avoid possible shock:
1. The Battery cables must be a minimum of 10 AWG.
2. Connect the positive (+) cable to the start solenoid on the engine.
3. Connect the negative (-) cable to one of the engine bolts.
4. Connect the positive (+) cable to the positive (+) terminal of the battery.
5. Then connect the negative (-) cable to the negative (-) terminal of the battery.
Disconnecting the
battery Always disconnect cables in the following sequence to avoid possible shock.
1. First, disconnect the negative (-) cable from the negative (-) terminal of the
battery.
2. Next, disconnect the positive (+) cable from the positive(+) terminal of the
battery.

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Breather
cap
Operation
INITIAL START-UP
1. Pump is shipped with oil. Remove the oil cap
and check pump oil level. Add SAE 30 non-
detergent pump oil (Part #4043), if necessary.
Hand tighten breather cap.
2. Turn pressure relief knob to engine start
position.
3. The engine is shipped without oil. Refer to the
engine manual for oil capacity and viscosity
recommendations.
4. Turn the gasoline line valve to the ON position.
5. For cold engine, move choke lever to full choke
position. To restart a warm engine, move choke
lever to half choke or to RUN position.
6. Start the engine:
A) Using electric start –
Turn the engine switch to the ON position.
Push and hold the START button until the
engine starts.
NOTE: If the engine fails to start after 5
seconds, release the START button and wait
10 seconds before attempting to start again.
Cranking the electric starter for more than 5
seconds continuously can overheat and
damage the starter motor.
Release the START button when the engine
starts.
B) Using recoil start –
Turn the engine witch to the ON position.
Pull the starter grip lightly until you feel
resistance, then pull the starter cord out
briskly and rapidly.
Allow starter cord to return slowly.
7. When engine starts, move choke lever to RUN
position.
8. Once the engine has started, move the pressure
relief knob to the engine run position.
9. CAUTION! Unusual noise or vibration indicates
a problem. Do not continue to operate until you
identify and correct the source of the problem.
10. CAUTION! Do not attach air tools to open end
of the hose until start-up is completed and the
unit checks out OK.
11. Run the unit for 30 minutes, with ball valve open,
to break in pump parts.
12. Close the ball valve to shut off airflow. The
compressor is now ready for use.
13. After 50 hours of operation change the
compressor oil.
WARNING!
Never disconnect threaded joints with pressure in
the tank.
NOTE: Reduce tank pressure below 10 psi, then
drain moisture from tank daily to avoid tank
corrosion. Drain moisture from tank by opening the
drain petcock located at the bottom of the tank.
COMPRESSOR LUBRICATION
CAUTION! Do not operate without lubricant or with
inadequate lubricant. Use of compressor without
lubricant or inadequate lubricant voids all warranties.
Synthetic Lubricants
Synthetic lubricants are recommended after 50-hour
break-in. Compressor life is greatly increased with
the use of synthetic lubricants. CAUTION! If you will
be using synthetic lubricant, all downstream piping
material and system components must be
compatible.
Suitable Viton®, Teflon®, Epoxy (Glass Filled), Oil Resistant
Alkyd, Fluorosilicone, Flourocarbon, Polysulfide, 2-Component
Urethane, Nylon, Delrin®, Celcon®, High Nitrile Rubber (Buna N.
NBR more than 36 Acrylonite), Polyurethane, Polyethylene,
Epichlorohydrin, Polyacrylate, Melamine, Polypropylene, Baked
Phenolics, Epoxy, Modified Alkyds
( ®indicates trademark of DuPont Corporation)
Not Recommended
Neoprene, Natural Rubber, SBR Rubber, Acrylic Paint, Lacquer,
Varnish, Polystyrene, PVC, ABS, Polycarbonite, Cellulose
Acetate, Latex, EPR, Acrylics, Phenoxy, Polysulfones, Styrene
Acrylonitile (San), Butyl
Alternate Lubricants. You may use petroleum-based lubricant
that is premium quality, does not contain detergents, contains
only anti-rust, anti-oxidation, and anti-foam agents as additives,
has a flashpoint of 440°F (227°C) or higher, and has a auto-
ignition point of 650°F (343°C) or higher.
See the petroleum lubricant viscosity table below. The table is
intended as a general guide only. Heavy duty operating conditions
require heavier viscosities. Refer specific operating conditions to
Powerhorse Product Support at 1-866-443-2576
Temperature around
Compressor Viscosity Grade
ISO SAE
Below 40°F (4°C) 60 20
40°F to 80°F
(4°C to 27°C)
100 30
80°F to 100°F
(27°C to 38°C)
150 40
Pump Capacities.
Refer to the following table for crankcase capacity
Item # Crankcase capacity
46851 48 oz
Engine start Engine run

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Maintenance
WARNING! Disconnect spark plug wire from spark plug and release air pressure from system before performing
maintenance.
NOTE: All compressed air systems contain maintenance parts (e.g. lubricating oil, filters, separators) which are
periodically replaced. These used parts may be, or contain, substances that are regulated and must be disposed
of in accordance with local, state, and federal laws and regulations.
NOTE: Take note of the position and locations of parts during disassembly to make reassembly easier. The
assembly sequences and parts illustrated may differ for your particular unit.
Daily or before each
operation •Check lubrication levels. Fill as needed.
•Drain receiver tank condensation.
•Check for unusual noise or vibration.
•Ensure belt guards and covers are securely in place.
•Ensure area around compressor is free from rags, tools, debris, and flammable or explosive
materials.
Weekly •Check safety/relief valves by pulling rings. Replace safety/relief valves that do not operate freely.
•Inspect air filter element. Clean if necessary.
Monthly •Inspect for air leaks. Squirt soapy water around joints during compressor operation and watch for
bubbles. Tighten fittings if necessary.
•Clean exterior.
3 months or 500
hours •Change petroleum lubricant while crankcase is warm.
12 months or 1000
hours •Replace air filter element.
DRIVE BELT
Belts will stretch in normal use. Properly adjusted, a
5 pound force applied to the belt between the motor
pulley and the pump will deflect the belt about 1/2”.
TO ADJUST DRIVE BELT:
1. Remove belt guard.
2. Loosen the four fasteners holding the engine to
the compressor.
3. Shift the engine in the proper direction. The belt
must be properly aligned when adjustment is made.
4. To align belt, visually center engine pulley to
compressor pulley.
6. If necessary, move the pulley on the engine
shaft.
7. Check for proper belt tension (see diagram).
8. Tighten the four fasteners holding the engine to
the top plate.
9. Attach belt guard.
Kits and Service Parts
Air filter: Part #35409
Non-detergent Oil: Part #4043
00882

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Exploded View 46851 - Rev. C
Ref Description Part # Qty
1 Engine, Powerhorse 414cc 785560 1
2 Throttle control 777868 1
3 Grommet 777146 1
4 Safety valve, 200 psi 35121 1
5 3/4” ball valve 35442 1
6 ¾” Closed nipple 780840 1
7 Air gauge, liquid filled 34699 1
8 ¼” NPT street tee 780433 1
9 Powerhorse decal 780307 1
10 30 Gallon receiver tank 780797 1
11 Operation instr. decal 36030 1
12 Warning hot decal 35064 1
13 Rotating equip. decal 35189 1
14 Drain valve 779577 1
15 Discharge tube 780837 1
16 5/8” comp. nut 34724 2
17 5/8” comp. sleeve 34723 2
18 5/8” comp. elbow 34937 1
Ref Description Part # Qty
19 Pump, B4900 779102 1
20 Intake manifold 35604 1
21 Air filter assembly 35603 1
22 Air filter 35409 1
23 Belt guard bracket 34785 1
24 Unloader valve 35626 1
25 Push To Start decal 780882 1
26 Switch bracket 780881 1
27 Start switch 30194 1
28 Wire assembly 780872 1
29 Wire assembly 780871 1
30 Belt guard 780492 1
31 CO warning decal 39259 1
32 Warning decal 34782 1
33 Sheave, AK59 777791 1
34 Belt, A60 37174 1
35 Bushing, H x 1” 777790 1
36 Belt guard cover 780493 1

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779102 Pump Assembly
Item Description Part # Qty
1 Pump Head AB4961400 1
2 Head Bolt (M8 x 55mm SHCS) AB9101744 6
3 Intercooler Gasket AB4650600 2
4 Intercooler/Aftercooler Bolt
(M8 x 20mm SHCS) AB9101254 8
5 Gasket AB3970200 2
6 Aftercooler AB2070100 1
7 Reducer AB9050282 1
8 Head Gasket AB4650400 1
9 Valve Plate Assembly AB4940050 1
10 Cylinder Gasket AB4950300 1
11 Cylinder, Cast Iron Sleeve AB4930000 1
12 Frame Gasket AB4950200 1
13 Cover N.D.E. AB2060690 1
14 Bearing Cover Gasket AB2050500 2
15 Bearing AB9170010 2
16 Oil Sight Glass AB9022001 1
17 Crankcase AB4960101 1
18 Cylinder Bolt AB9107254 6
19 Crankcase Plug AB9101164 1
20 Crankcase Bolt (M5 x 15 HHCS) AB9114271 12
21 Crankcase Pan AB4961301 1
22 Crankcase Gasket AB4950101 1
23 Crankshaft AB4961200 1
24 Nut AB9128234 4
25 Oil Seal AB9163010 1
26 Cover D.E. AB2060590 1
Item Description Part # Qty
27 Cover Bolt (M6 x 15 SHCS) AB9101094 8
28 Flywheel, 350 mm AB3600100 1
29 Flywheel washer AB9004008 1
30 Screw, Reverse Thread AB9110014 1
31 Half Bearing AB9013011 4
32 Connecting Rod AB4011101 2
33 Wrist Pin AB4621200 1
34 H.P. Piston, Aluminum AB4621100 1
35 Circlip AB9140050 4
36 Piston Ring ROF AB9020086 2
37 Piston Ring ROS AB9020053 1
38 Piston Ring AC AB9020023 1
39 Rod Bolt AB9106244 4
40 L.P. Piston, Aluminum AB4922100 1
41 Wrist Pin AB4922200 1
42 Piston Ring ROF AB9020057 1
43 Piston Ring ROS AB9020056 1
44 Piston Ring AC AB9020055 1
45 Breather Cap AB9024010 1
46 Intercooler AB4662000 1
47 Safety Valve AB9049064 1
48 Air Filter Assembly 35603 1
49 Air Filter 35409 1
50 Intake Manifold 35604 1
Complete Gasket Kit AB4950055 1
00863

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Pneumatic Schematic Diagram
Safety
Relief
Valve
Pump
Idle Down
Unloader
Safety
Relief
Valve
30 Gallon Tank

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Troubleshooting
This section provides a list of the more frequently encountered compressor malfunctions, their
causes and corrective actions. Some corrective actions can be performed by the operator or
maintenance personnel, and others may require assistance of a qualified electrician or Service
Center.
PROBLEM POSSIBLE CAUSE
Engine does not start. A,B,C,D,E
Air delivery drops off. H, I, J, L, M, N, P
Compressor does not come up to speed. F, G, J, K
Compressor is slow to come up to speed. F, G, J, K, L
Compressor will not unload cycle. H, L, N, P
Compressor will not unload when stopped. H, L, N, P
Excessive starting or stopping. N, Q, S
Moisture in crankcase, “milky” substance in oil. R
Oil in discharge air. T
Safety/relief valve “pops”. L, M, N
Low interstage pressure. W
High interstage pressure. V
POSSIBLE CAUSE POSSIBLE SOLUTION
A.) Low Oil Shutdown Fill engine with the adequate amount of oil.
B.) Cold Engine Choke engine to start.
C.) No Fuel Add gas to engine. Make sure fuel shutoff valve is open
D.) Engine not turned ON Place ON/OFF switch in the ON position.
E.) Spark plug wire not attached Attach spark plug wire to spark plug.
F.) Compressor viscosity too high for ambient temperature. Drain existing lubricant and refill with proper lubricant.
G.) Belt tension too tight or sheaves not aligned. Check tension/ alignment.
H.) Air leaks in discharge piping. Check tubing connections, Tighten joints or replace as required.
I.) Compressor components leaky, broken, loose. Inspect components. Clean or replace as required.
J.) Loose flywheel or motor pulley, excessive end play in motor shaft
or loose drive belts. Check flywheel, motor pulley, and crankshaft drive belt tension/alignment. Replace or repair as required.
K.) Leaking check valve or check valve seat blown out. Replace check valve.
L.) Clogged or dirty inlet and/or discharge line. Clean or replace.
M.) Defective safety/relief valve. Replace.
N.) Pressure switch unloader leaks or does not work. Realign stem or replace.
O.) Inadequate ventilation around flywheel. Relocate compressor for better air flow.
P.) Leaking, broken or worn inlet unloader parts at check valve. Inspect parts and replace as required.
Q.) Excessive condensation in receiver tank. Drain receiver tank.
R.) Detergent lubricant in crankcase. Replace with proper lubricant.
S.) Light duty cycle. Increase duty cycle.
T.) Lubricant level too high. Drain excess lubricant.
U.) Worn cylinder finish. Deglaze cylinder with 180 grit flex-hone.
V.) Low pressure inlet valve leaking. Inspect, clean or repair as required.
W.) High pressure inlet valve leaking. Inspect, clean or repair as required.
Any Questions, Comments, Problems or Parts Orders
Call Powerhorse Product Support 1-866-443-2576

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Limited Warranty
Dear Valued Customer:
The Powerhorse Product you just purchased is built with the finest material and craftsmanship. Use this
product properly and enjoy the benefits from its high performance. By purchasing a Powerhorse product, you
show a desire for quality and durability. Like all mechanical equipment this unit requires a due amount of care.
Treat this unit like the high quality piece of machinery it is. Neglect and improper handling may impair its
performance. Please thoroughly read the instructions and understand the operation before using your product.
Limited Warranty
Powerhorse shall warranty any piece of equipment manufactured, or parts of equipment manufactured, to be
free from defects in material or workmanship for a period of 2 years for noncommercial/nonrental use and a
period of 90 days for commercial/rental use from the date of purchase by user.
Powerhorse shall warranty any wear item, including, but not limited to, valves, seals, pump diaphragms, hoses,
and filter elements to be free from defects in material or workmanship for a period of 90 days from the date of
purchase by user. This warranty applies to the original purchaser of the equipment and is non transferable.
Verification of purchase is the responsibility of the buyer. Parts will be replaced or repaired at no charge, except
when the equipment has failed due to lack of proper maintenance. Any misuse, abuse, alteration or improper
installation or operations will void warranty. Determining whether a part is to be replaced or repaired is the sole
decision of Powerhorse.
NOTE: Some services performed by parties other than Powerhorse may void warranty.
This warranty covers parts only. It will not provide for replacement of complete products due to defective parts.
Components not manufactured by Powerhorse are guaranteed by their manufacturer and can be serviced at
factory-authorized locations near you. Any costs incurred due to replacement or repair of items outside of a
Powerhorse approved facility is the responsibility of the buyer and not covered under warranty. Powerhorse can
supply you with the service center location in your area.
This warranty specifically excludes the following; failure of parts due to damage caused by accident, fire, flood,
windstorm, acts of God, applications not approved by Powerhorse in writing, corrosion caused by chemicals, use
of replacement parts which do not conform to manufacturer’s specifications, and damage caused by vandalism.
Additional exclusions: loss of running time, inconvenience, loss of income, or loss of use, including any implied
warranty of merchantability of fitness for a specific use.
Warranty does not cover items subject to normal wear such as tires, receptacles or any part subject to direct
physical contact by the public. This warranty does not cover any personal injury or damage to surrounding
property caused by failure of any part.
This warranty is in lieu of any other warranty expressed or implied and Powerhorse assumes no other
responsibility or liability outside that expressed within this warranty.
Please fill in the following information and have it on hand when you call in on a warranty claim.
Customer Number: ______________________________________________________________
Date of Purchase: _______________________________________________________________
Powerhorse Serial Number: _______________________________________________________
Item Number: __________________________________________________________________

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Manufactured by
Northern Tool + Equipment Co.,
2800 SouthCross Drive West
P.O. Box 1499 Burnsville, MN 55337-0499