Te c h n o l o g y, L L C

TABLE OF CONTENTS
How it Works . . . . . . . . . . . . . 1
“Seeing is Believing®” . . . . . . . . . 2
Important Safety Precautions . . . . . . 3
Fuel Pro 382 Dimensions . . . . . . . . 4
Installation Instructions . . . . . . . . . 5
Fluid Heater Installation . . . . . . . . . 7
12 VDC and 24 VDC
Electric Pre-heater Installation . . . . . . 8
Water in Fuel Sensor (WIF) Installation . . . 9
Preventive Maintenance . . . . . . . . . 10
Visual Diagnostics . . . . . . . . . . . 12
Diagnostic Procedures . . . . . . . . . 14
Check Valve Diagnostics . . . . . . . . 17
Service Parts . . . . . . . . . . . . . 18
Warranty and Customer Service . . . . . 19

FOR UPDATED INFORMATION, VISIT WWW.DAVCO.COM

FUEL PRO 382

®

TECHNICAL MANUAL
2011 ©DAVCO Technology, LLC.
Updated 08/29/2011
 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

HOW IT WORKS
• Fuel from the tank enters the Fuel Processor body (suction side of the fuel system).
• Large contaminants and “free” water are separated from the fuel and remain in the body.
• Fuel rises into the clear cover.
• Contaminants and emulsified water are captured by the filter media.
• Fuel level rises to maintain a fuel path through the clean filter media with low restriction.
• Clean, water-free fuel exits the Fuel Processor and flows to the engine fuel injection system.

Fuel System Diagram

FUEL TO ENGINE
FROM FUEL PRO

FUEL PRO LIFT PUMP

382
INJECTION
PUMP

ENGINE

FUEL FROM FUEL TANK

TO FUEL PRO

FUEL TO FUEL TANK

FUEL TANK

Figure 1

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“SEEING IS BELIEVING®”
• See when NOT to change the fuel filter.
• See the condition of the fuel. Seeing what collects on the filter media or what’s happening inside the clear cover
can help diagnose many fuel and mechanical conditions.
• “Filter on Top” configuration. Water and debris removed from the fuel falls to the lower chamber and stays away
from the filter media resulting in longer filter life.
• Built in protection when priming the fuel filter. Unfiltered fuel is kept on the “dirty” side of the filter media during
priming ensuring only clean fuel reaches the engine.
• Patented media. The “Best in Class” StrataPore™ media removes 98% of free and emulsified water over the life of
the filter. This far exceeds the performance of cellulose media.

When new, the fuel level in the filter will be very Fuel level increases in clear cover. As contaminants
low with minimal restriction. As the filter is used, collect on the filter, the fuel rises to a non-contami-
contaminants collect on the filter from the bottom up. nated section of the filter, providing optimal filtration
Fuel rises on the filter indicating remaining filter life. while maintaining lowest restriction.

Fuel level at filter wrap level. Even though the fuel The filter element is now completely covered by
level is now more than half of the filter element, the fuel. At this point, all of the media’s surface area is
fuel is still flowing through clean media at minimal utilized. Restriction is increasing and the filter element
restriction levels. The filter still has significant life should be changed at the next scheduled mainte-
remaining. nance interval.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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IMPORTANT SAFETY PRECAUTIONS

WARNING: When diesel fuel is circulated through an operating engine, it can become very hot.
To prevent personal injury:
몇 Scalding hazard! Do not allow fuel to come in contact with eyes or unprotected skin. Allow the engine and fuel
to cool to ambient temperature before replacing the fuel filter or performing service operations which could result
in spillage of fuel from the fuel system. If this is not possible, protective equipment (face shield, insulated hat,
gloves, and apron) must be worn.

몇 Fire Prevention! Heated diesel fuel can form combustible vapor mixtures in the area around the fuel source. To
eliminate the potential for fire, keep open flames, sparks or other potential ignition sources away from the work
area. Do not smoke during filter replacement or service operations.

몇 Inhalation Prevention! Always perform engine or vehicle fuel system maintenance in a well ventilated area that
is kept free of bystanders.

몇 The ignition key must be in the off position.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

FUEL PRO 382 DIMENSIONS

6.75 (171.5) MAX

SERVICE HEIGHT
1.5 (38.1)

3.28 (83.3) 3.9 (99.1)

16.00 (406.4) MAX

1/2" x 14
NPTF
FUEL INLET

1/2" x 14 NPTF FUEL

FUEL OUTLET IN
Ø .43 (11.0)
(2 PLACES)

5.91 (150.0) 3.46 (88.0)

FRONT RIGHT SIDE

6.58 (167.1)

.50 (12.7)

BOTTOM
All dimensions are in inches (millimeters)

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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INSTALLATION INSTRUCTIONS
Installation Location Fuel Line Routing
The Fuel Pro must be installed between the fuel tank and To minimize fuel system restriction, observe the follow-
the fuel transfer pump. In some cases, the Fuel Pro can be ing guidelines when plumbing the fuel system:
used as the only fuel filter in the system. This is generally • Keep the fuel line routing as smooth as possible with no
dependent on the engine model year. Consult the engine low-hanging loops which can trap water.
manufacturer for their recommendation. If the Fuel Pro can
• Use 90° elbows only when necessary.
be used as a single filter, DAVCO offers a diverter cap to
replace the secondary filter. (See diverter cap installation • If the fuel hoses are cut to length on the job, be sure that
section) the inner liner of the fuel hose is not cut by the fitting,
which can cause check valve performance issues. Make
sure hoses are clean and free of debris before installing.
Mounting the Fuel Pro
• To avoid damaging the aluminum Fuel Pro body, do not
Mount the Fuel Pro keeping the following points in overtighten fuel lines or fuel line fittings.
mind:
Step 1: Route the fuel supply line from the pick up on the
• Do not install the Fuel Pro directly on the engine.
fuel tank to the Fuel Pro inlet (labeled “Fuel In”).
• Mount vertically with the cover and element pointing
Step 2: Route the fuel outlet line from the Fuel Pro outlet
up.
(labeled “Fuel Out”) to the inlet of the fuel pump.
• Make sure there is enough top and side clearance for
the cover to be conveniently removed for filter replace-
ment. Priming the Fuel System
• The Fuel Pro MUST be installed so that the Filter Ele- Step 1: Check to make sure the drain valve at the base of
ment is above the "FULL" level of the fuel tank. the Fuel Pro is closed.
Step 1: With the engine shut down and at ambient temper- Step 2: Remove the vent cap from the top of the clear
ature, close the fuel shutoff valve (if equipped) and place a cover. Fill the Fuel Pro full with clean fuel. Reinstall the vent
suitable container under the fuel filters. cap and tighten by hand only.
Step 2: Remove the primary fuel filter element assembly, Step 3: Start the engine. When the lubrication system
sedimenter, and/or water separator. Drain the used ele- reaches its normal operating pressure, increase engine
ment and dispose of it in an environmentally responsible RPM to high idle for one to two minutes. After the air is
manner, according to state and/or federal (EPA) recom- purged loosen the vent cap until the fuel level lowers to
mendations. just above the collar. Tighten the vent cap by hand only.
Step 4: Hand tighten the collar again while the engine is
running. To avoid damage, do not use tools to tighten the
collar.
Note: The clear filter cover will not fill completely during
engine operation. It will gradually fill over time and the fuel
level will rise as the filter becomes contaminated.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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INSTALLATION INSTRUCTIONS
Diverter Cap Installation Diverter Cap Required Required Required
If a single fuel filter system is approved by the engine Part Number Filter Head Filter Head Filter Head
manufacturer, the following steps are to be taken to install Stud Size Seal ID Seal OD
a diverter cap properly. 101480 1"-14 2.475" 2.895"
Step 1: Select the required secondary filter head diverter 101589 1"-14 3.225" 3.435"
cap from those listed in Table 1. The required diverter cap 101570 M16 x 1.5 2.475" 2.895"
is determined by the size of the spin-on filter stud and the
filter sealing surface diameter. 101466 ¾"-16 2.475" 2.895"
101492 7/8" x 14 2.475" 2.895"
Step 2: Drain and remove the secondary fuel filter element.
Step 3: Lightly lubricate the seal on the top of the diverter Table 1
cap with clean engine oil.
Step 4: Thread the adapter onto the secondary filter stud
and tighten by hand only.
Step 5: Install the “Do Not Remove” label on the diverter
cap.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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FLUID HEATER INSTALLATION

The engine return fuel heat and engine coolant heat options apply ONLY to the fluid heater base shown in Figures 2 and
3. If the bottom plate is flat with ½" NPT ports, only the electric pre-heater can be used. Contact DAVCO Customer Ser-
vice to obtain the appropriate bottom plate.

Engine Coolant Heat Engine Return Fuel Heat

To use engine coolant as the Fuel Pro heating fluid, con- High flow and high temperature return fuel engines can
nect a hose (5/8" silicon heater hose) from the high pres- use the return fuel as the heating fluid for the Fuel Pro.
sure side of the engine coolant system to the Fuel Pro Route the return fuel line from the engine into the heater
heater base. Either heater port will work as an inlet. Route base of the Fuel Pro. Either heater port will work as an in-
another hose from the heater base to a low pressure port let. Connect a second fuel return line from the heater base
in the coolant system. DO NOT route into the cab heater to the fuel tank return port.(See Figure 3)
system. (See Figure 2)

return fuel
Fuel Pro Fuel Pro
transfer pump transfer pump

fuel tank fuel tank

coolant

inlet or outlet ports inlet or outlet ports

Figure 2 Figure 3

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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Te c h n o l o g y, L L C TECHNICAL MANUAL

12 VDC AND 24 VDC ELECTRIC PRE-HEATER INSTALLATION

Installing 12 VDC and 24 VDC Pre-heater Wiring without Relay
Electric Pre-heaters
The Fuel Pro 382 12 VDC or 24 VDC electric pre-heater is FUEL PRO

installed in the processor base as shown in Figure 4.

Key Controlled Circuit

Fuse*

Switch Heater element

20 A
+
Battery

GND GND

*24 VDC pre-heaters require a 15 A fuse.

Figure 5

Figure 4
Pre-heater Wiring with Relay
Step 1: Drain all the fuel from the Fuel Pro. The fuel can
be reused after the pre-heater is installed. If the fuel is not FUEL PRO

reused, dispose of it in an environmentally safe way.

Step 2: Remove the pipe plug in the Fuel Pro base plate.
Fuse*
Step 3: Apply liquid thread sealant to the pre-heater
threads and install into the Fuel Pro base. Tighten to 15-30 20 A Heater element
+
ft-lbs. Battery
Key Controlled Circuit
Step 4: Connect the chassis harness and wire. Relay

• For 12 VDC or 24 VDC without a relay, refer to Figure 5. GND

GND GND

• For 12 VDC or 24 VDC with a relay, refer to

Figure 6. *12 VDC pre-heaters require a 20 AMP fuse. If the keyed circuit will not
handle a minimum of 20 amps, use a relay.
• If the keyed circuit will not handle a minimum of 20
amps, use a relay.
Figure 6
• Provide proper (20 amp fuse) electrical protection for
source voltage supplied to the pre-heater.
Step 5: Remove the vent cap from the top of the clear
cover. Pour fuel into the Fuel Pro to one inch below the
top of the filter element. Reinstall the vent cap and hand
tighten.
Step 6: Start the engine. When the lubrication system
reaches its normal operating pressure, increase engine
speed to high idle for one to two minutes. After the air is
purged, loosen the vent cap until the fuel level drops to
just above the collar. Tighten the vent cap by hand only.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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WATER IN FUEL SENSOR (WIF) INSTALLATION

Step 1: Remove the ½"-20 WIF plug in the bottom of the Step 7: Connect the black ground lead with a 3/8" diam-
Fuel Pro. eter loop end on the WIF wiring harness to the ground
Step 2: Install the WIF Probe (See Service Parts Page source near the Fuel Pro (if applicable).
for P/N) into the bottom of the Fuel Pro. Torque to 20-24 Step 8: Connect the green signal wire on WIF wiring
in-lbs. harness to green signal wire on WIF indicator light. Use
Step 3: Install the WIF wiring harness (P/N 102600) on additional green wire as needed.
WIF Probe. The harness has the following connections: Step 9: Locate 12 VDC or 24 VDC key controlled on
black ground lead with a 3/8" diameter ring terminal and power source. Install a red wire from the power source to
a green WIF wire. the red wire on WIF indicator light. Add a 1 amp in-line
Step 4: Drill ½" hole in the instrument or control panel fuse (not included).
where the WIF indicator light is to be located. Note: Use appropriate connectors to attach the wires. To
Step 5: Connect the black ground wire from the WIF test the WIF indicator light, pour water into the body of
indicator light to a ground source. Attach additional black the Fuel Pro until it covers the WIF probe. The WIF indica-
wire as needed. tor light should illuminate.

Step 6: Install the WIF indicator light by pressing firmly

into the drilled hole.

WATER-IN-FUEL
(WIF) FUEL
WARNING LIGHT

WATER

PROBE

TO ANY KEYED
12 OR 24 VDC SOURCE RED GREEN

BLACK

CHASSIS
CHASSIS GROUND
GROUND

(Recommended fuse: 500ma for 12 VDC. Do not exceed 1 A.)

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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Te c h n o l o g y, L L C TECHNICAL MANUAL

PREVENTIVE MAINTENANCE
• Weekly – Drain water
• Turn off the engine and open the vent cap.
• Place a suitable eight ounce, plastic or metal container under the drain valve at the base of the Fuel
Pro and open the valve.
• Water will flow into the container. When fuel begins to flow out the drain, close the drain valve. Drain
the least amount of fuel as possible.
• Hand-tighten the vent cap.
• Start the engine. Raise the RPM for one minute to purge the air from the system.
• Every filter change
• Change the cover and vent cap o-rings (included with the service filter kit).
• Every 12 months
• Check all electrical connections for corrosion. Check all fuel fittings for leaks.
• Extreme winter or salt corrosion environments may require lubrication of the collar threads with
anti-seize lubricant every 180 days.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

FILTER CHANGE PROCEDURE

Filter Change Step 6: Reinstall the clear cover and collar. Hand tighten
the collar.
For filter selection visit www.davco.com/parts.html (Parts
And Cross Reference) for the correct filter for your applica- Step 7: Prime the unit by filling the clear cover with clean
tion or call DAVCO Customer Service at 800-328-2611. diesel fuel until it reaches the top of the filter.
Step 1: Remove the vent cap and open the drain valve to Step 8: Install the vent cap. Hand tighten only.
drain the fuel below the collar level. Step 9: Start the engine and run for one minute. Slowly
Step 2: Remove the collar (using the DAVCO collar open the vent cap and allow the fuel to drop to about one
wrench) then remove the clear cover. inch above the collar.
Step 3: Remove the filter, cover and vent cap seals. Step 10: Close the vent cap. Hand tighten only. It is
Dispose of the filter and the seals properly. normal for the fuel level to vary after the initial start-up and
during engine operation. Filter performance is not affected.
Step 4: Using a clean shop rag, clean the cover, the collar
and threads on the Fuel Pro body.
Step 5: Install a new filter, cover seal and vent cap seal.

Service Wrench Information

• The DAVCO Fuel Pro vent cap and collar are
designed to be removed with a DAVCO wrench.
• Vent caps and/or collars damaged as a result of
not using the DAVCO wrench will not be covered
under warranty. Wrench is for removal ONLY.

Description P/N
Metal Collar/Vent Cap Wrench
Metal Collar/Vent Cap Wrench 380134

Composite Collar/Vent Cap Wrench 382002

Composite Collar/Vent Cap Wrench

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

VISUAL DIAGNOSTICS
Fuel level is not at the top of the fuel Fuel level is at the top of the filter. Low
filter. power.
Normal - Do not change the filter. Change the filter at the first available
opportunity.

Fuel level is at the top of the filter and There is a power complaint and the fuel
appears to be full of wax. level is below the collar.
Change the filter - Run the engine for Check for a missing grommet at the
a minimum of 25 minutes at idle. Do not lower end of the filter or missing/broken
run at full RPM. spring at top of filter.

Bubbles are seen flowing in with the Water is noticed in the cover.
fuel. Drain the water. If engine coolant is
Check all fittings and lines from the visible, follow proper engine pressure
fuel tank to the fuel processor. Check testing procedures to determine root
lower and upper collar o-rings. cause.

Fuel drains back to the fuel tank when No engine coolant flow to the Fuel Pro
changing the fuel filter or draining sepa- heater.
rator. Check for closed cutoff valves at
Remove the check valve assembly. the coolant lines to the fuel processor.
Clean or replace and retest. Check air Make sure the cab heater valve is open.
leaks in the fuel system.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

VISUAL DIAGNOSTICS
There are two kinds of bubbles that may be visible at the fuel pump inlet of a diesel fuel system. The bubbles can be
characterized as either air bubbles or vapor bubbles.

Air Bubbles Vapor Bubbles

(will affect engine performance) (will not affect engine performance)
Air bubbles are caused by any air leak on the vacuum (suc- All diesel fuel has some level of entrained air caused by the
tion) side of the fuel system from the fuel tank pick-up to, natural splashing that occurs in the fuel tank during normal
and including, the lift pump. (See Figure 7) vehicle or equipment operation. Vapor bubbles develop in
If there is an air leak in the fuel system, air bubbles will the Fuel Pro because the pressure inside the Fuel Pro is
be present in the clear cover of the Fuel Pro. Follow test lower than the atmospheric pressure in the fuel tank. Vapor
procedures outlined in "Troubleshooting" for air leak diag- bubbles can vary from champagne size up to ¼" in diam-
nostics. eter. They may increase in size or volume as engine RPM
increases. The lower pressure draws the entrained air/va-
If there are no bubbles present in the Fuel Pro cover and
por out of the fuel and these bubbles will be visible as the
the engine continues to run rough, lopes or has a loss
fuel exits the Fuel Pro. (See Figure 8)
of power, there may be an air leak between the Fuel Pro
outlet port and lift pump inlet. This type of air bubble can As the fuel enters the lift pump, it is pressurized and the
be seen if a sight tube is installed at the lift pump inlet. Air bubbles are compressed back into the fuel. There will be
bubbles may also be visible in the fuel return (spill) hose no bubbles on the fuel return side of the system. (See Fig-
out of the fuel gallery. These leaks are easily eliminated by ure 8). These vapor bubbles will not affect the performance
checking and torquing the fuel fittings in the area of the of the engine.
leak. There is no diagnostic or repair procedure required for
If there are no air leak symptoms, but bubbles are pres- vapor bubbles. Vapor bubbles do not cause performance
ent in a sight tube at the fuel lift pump inlet, they are most issues and will not be present after the lift pump.
likely vapor bubbles.
Note: A quick procedure to determine if the air leak is
between the fuel tank and the Fuel Pro is to remove the
Fuel Pro inlet hose and route a new hose from the Fuel Pro
inlet into a container of fuel or the fuel tank fill cap opening.
Start the engine and check for bubbles.

ENGINE ENGINE
FUEL RETURN FUEL RETURN

LIFT PUMP LIFT PUMP

AIR
FUEL PRO VAPOR FUEL PRO
BUBBLES OR OTHER OR OTHER
PRIMARY
FILTER
BUBBLES PRIMARY
FILTER

Figure 7 Figure 8

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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

DIAGNOSTIC PROCEDURES
Air Leaks drain valve and/or check valve. If the
Every Fuel Pro is factory tested for leaks and is identi- Fuel Pro is equipped with a pre-heat-
fied with a traceable number prior to shipment. Most field er, do not remove the pre-heater.
issues associated with leaks are related to loose fittings. 3. Apply 15 PSI of air pressure at the
These leaks are easily eliminated by checking and torqu- fuel inlet. Immerse the Fuel Pro in a
ing the fuel fittings in the area of the leak. Some fittings tank of water and look for air bub-
may also require the application of liquid Teflon sealer. bles.
Note: All suction side fuel filters experience bubbles. It 4. Correct the source of the air leak and
is normal to see champagne size bubbles in the Fuel Pro retest.
cover, at the Fuel Pro outlet or at the lift pump. B. Bubbles Not Visible: If there are symptoms of
IN ORDER TO RETURN A FUEL PRO FOR EVALU- sucking air (indicated by engine loping/rough
ATION, THE FOLLOWING PROCEDURES/TESTS running performance/power loss, etc.) and
MUST BE COMPLETED BEFORE REQUESTING A there are no bubbles in the clear cover, the air
DAVCO RGA (RETURN GOODS AUTHORIZATION) leak is either at the Fuel Pro outlet fitting, vent
NUMBER. cap o-ring, the lift pump inlet connection, or the
fuel hose/connections to the lift pump. Inspect
I. Air Leak: Air bubbles will be visible in the clear cover
and tighten fittings as needed.
of the Fuel Pro if the leak originates between the fuel
tank up and the fuel filter. The following is a quick test II. Excessive Restriction: If the fuel level is at the top
to isolate the air leak source. of the filter, replace the fuel filter. The Fuel Pro will
not cause excess system restriction if the fuel level
A. Bubbles Visible: Remove the Fuel Pro inlet
is below the top of the filter. The only exception is if
hose.
the grommet is not installed in the bottom of the filter
i. Install a jumper hose from the Fuel Pro to element.
the fuel tank (through the fill cap) or to a
III. Loss of Prime: When air is introduced into the fuel
container of fuel.
system, (i.e. draining water from the Fuel Pro or when
ii. Start the engine. If this eliminates the air replacing the fuel filter) a check valve is needed to
bubbles, the air source is at the fuel tank keep the fuel system primed from the Fuel Pro back
fittings or hose connections. to the fuel tank. A check valve is standard with every
1. Tighten all fittings and connectors Fuel Pro
2. Retest A. To test for proper check valve operation,
iii. If air bubbles persist, the air source is on remove the fuel inlet hose and open the vent
the Fuel Pro side of the system: cap. Fuel should not flow out of the Fuel Pro ,
although a slight seepage of fuel is normal.
1. Tighten all fittings on the Fuel Pro .
B. If fuel drains back to the fuel tank, remove the
2. Hand tighten the top collar.
check valve assembly at the fuel inlet fitting.
3. If the drain valve is suspected, install Disassemble the check valve assembly. Clean
a plug in place of the drain valve (for and inspect. Replace the assembly if any cuts,
test purposes only). grooves or nicks are evident in the ball or body
iv. If air bubbles continue to persist, test as seat. Reinstall the check valve assembly.
follows:
1. Remove the Fuel Pro from the chas-
sis.
2. Plug the fuel outlet port. Do not
remove filter, cover/collar, vent cap,

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

DIAGNOSTIC PROCEDURES
Fluid Heater Thermovalve Test Electric Pre-Heater and Thermoswitch
Step 1: Drain the Fuel Pro completely. Tests
Step 2: Remove the fluid hoses going to the bottom plate.
These will either be engine coolant hoses or return fuel Equipment Needed:
hoses. Engine coolant hoses will have to be plugged when • A precision low resistance Ohm Meter capable of mea-
removing them from the Fuel Pro. suring 1/10th Ohm or less is recommended.
Step 3: Remove the bottom plate. • Current Flow Meter (Clamp-on type for DC current).
Step 4: While looking into the fluid port of the bottom plate • Ice, dry-ice, CO2 or some means of chilling the thermo-
(see Figure 9) flow cold water over the thermovalve for switch.
30 seconds, then run hot water over the thermovalve and • A flameless source of heat. Infrared heat lamp, etc. (a
determine if the thermovalve spool is opening and closing. Vortex tube is a good tool to heat and cool for testing).
Step 5: Replace with a new bottom plate seal and install  DO NOT USE a test light that has a wire probe for
the bottom plate onto the Fuel Pro. any of these tests. If the insulation of the wiring is
Note: There are two styles of bottom plates. punctured, moisture and road salt can penetrate into
the wires creating a corrosion issue and potential
• Torque the collar version to 50 to 60 ft-lbs (the use of failure.
2-3 drops of Loctite 406 is recommended to secure the
bottom collar). Use seal P/N 101994. There are various configurations of electric pre-heaters and
thermoswitches available for the Fuel Pro. These include
• Torque the bolts on the bolt-on version bottom plate to
12 VDC pre-heaters, 24 VDC pre-heaters, 120 VAC pre-
10 ft-lbs. Use seal P/N 910005.
heaters, thermoswitch, and combination pre-heater ther-
Step 6: Reconnect the fluid hoses to the bottom of the moswitch. The voltage and wattage ratings are stamped
Fuel Pro. either on the sheath or the hex of each component for
Step 7: Fill the Fuel Pro with fuel and restart the engine. identification.
If it is necessary to remove the fuel from the fuel/water
separator:
• Shut off the engine and set the parking brake.
• Attach a length of hose to the drain valve and into a
Thermovalve container.
• Loosen the vent cap on top of the clear housing, and
open the drain valve to drain the fuel into the receptacle.
• When the fuel is drained, close the drain valve.

Pre-heater Test
Step 1: Disconnect the pre-heater from the harness.
Step 2: Connect the Ohm meter leads to the pins of the
pre-heater (connect to a pin and the bushing for pre-
heaters with one pin).
Port to view Step 3: Using the Table 2, read the value of the resistance
thermovalve and determine if the pre-heater is within the acceptable
spool range.

Figure 9

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

DIAGNOSTIC PROCEDURES
Electric Resistance Range diesel fuel until it reaches the top of the filter.
Watts
Pre-heater in Ohms Step 5: Install the vent cap. Hand tighten only.
12 VDC (two pin) 250 W 0.6 to 0.8 Step 6: Start the engine and run for one minute. Slowly
open the vent cap and allow the fuel to drop to about one
12 VDC (single pin) 250 W 0.6 to 0.8
inch above the collar. Close the vent cap. Hand tighten
12 VDC (single pin) 150 W 0.8 to 1.1 only.
12 VDC (two pin) 150 W 0.8 to 1.1
24 VDC (two pin) 250 W 2 to 2.5
24 VDC (single pin) 250 W 1.8 to 2.3
24 VDC (single pin) 150 W 3.6 to 4.1
120 VAC 75 W 173 TO 203
120 VAC 37 W 369 TO 411
Table 2

12 VDC Thermoswitch Test

Step 1: Disconnect the thermoswitch harness (see Figure
10).
Step 2: Connect the Ohm meter leads to the pins of the
thermoswitch.

Figure 10
Note: This test requires the thermoswitch to be below 40°
F. (Use one of the cooling sources listed under "Equipment
Needed".) The resistance should be less than 0.1 Ohm.
Step 3: Using one of the heat sources listed under "Equip-
ment Needed", raise the temperature above 60° F. The
resistance should be more than 10M Ohms.
Step 4: Prime the unit by filling the clear cover with clean

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

CHECK VALVE DIAGNOSTICS

To test for proper check valve operation, remove the fuel Note: The spring retainer snaps into a groove in the check-
inlet hose and open the vent cap. Fuel should not flow out valve body.
of the Fuel Pro, although a slight seepage of fuel is normal.
Step 5: Replace the check valve assembly into the body
If fuel drains back to the fuel tank, remove the check valve and torque to 44-60 ft-lb.
assembly at the fuel inlet fitting.
Step 6: . Connect the fuel inlet hose, using liquid or paste
Step 1: Use a back-up wrench to hold the check valve type thread sealant.
body and remove the fuel hose from the inlet of the Fuel
Pro. Step 7: Prime the fuel system, start the engine and check
for any fuel leaks.
Step 2: Remove and disassemble the check valve assem-
bly.
Check Valve Body Check Valve Service Kit
Step 3: Clean and inspect the check valve body. Replace
the check valve body if any cuts, grooves or nicks are
evident or if the ball seat is not smooth.
Step 4: Inspect the check valve spring and spring retainer.
If the spring or spring retainer is broken or if the check ball
has groves, nicks or is out of round, replace with a check
valve service kit. Otherwise, clean and reassemble the
check valve assembly. P/N 090037 P/N 101132

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

SERVICE PARTS
Service Parts Visit www.davco.com for OEM service part number listing.

Description Part Number

Collar 102425
Clear Cover 102420
Spring 380056 Collar
visit www.davco.com/parts.html
Filter Element Vent Cap Kit
for filter ordering information.
(part no. 380043)
Drain Valve 102008 Includes Vent Cap
Electric Pre-heaters visit www.davco.com, Form F1263 with vent cap seal installed.

WIF See Page 9

Check valve body 090037
Spin-on stud
13/16"-12 320620
(Yellow Zinc)

Check Valve Body O-Ring Kit

Spring (part no. 380072)
Includes a vent cap seal
and a cover seal.

Filter
Check Valve Service Kit: P/N 101132

Service Kits
Description Contents Part Number
Vent cap and
Vent cap ser- Spin-on Stud
Vent cap 380043
vice kit
O-ring
O-ring Vent cap and Cover
380072
service kit O-rings
Check Valve
Retainer, spring and Service Kit
Check valve
ball (does not include 101132
service kit
the check valve body)
Drain Valve

OR
DAVCO Wrenches
Description Part Number
Check Valve Body

Metal Col- Check Valve

lar/Vent Cap 380134 Service Kit
Wrench

Heated
Composite
Drain Valve
Collar/Vent 382002
Cap Wrench

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

SERVICE PARTS
Bottom Plate - Service Kits and Parts
Description Part Number
Seal (Bottom Collar) 101994
Seal (Bolt-On) 910005

Unheated Bottom Plate (Bottom

382006SVC
Collar)

Fluid Heated Bottom Plate (Bottom

382015SVC
Collar)

Unheated Bottom Plate (Bolt-On) 382027SVCB

Bottom Plate Upgrade: Includes:

Radiator o-rings (2)
Thermo-Valve Assembly
Bottom plate seal (square cut) 382029SVCB-1
Spool assembly
Bottom plate plug w/o-ring

Pre-heater - Service Parts

120 VAC Preheater

120 VAC “Y” Cord 102015

120 VAC Straight Cord 101868

*Note: See Form www.davco.com, Form F1263 for 12 VDC and 24 VDC Pre-heaters. For Specific OEM numbers for
pre-heaters, contact customer support at 1-800-328-2661

Visit www.davco.com for OEM service part number listing.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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Te c h n o l o g y, L L C TECHNICAL MANUAL

SERVICE PARTS
Water-in-Fuel (WIF) Service Parts

1 Pin WIF sensor 101017

2 Pin WIF sensor

102507
(Fleetguard and Bus Applications)

2 Pin WIF harness

102519
(17" Freightliner Chassis)

2 Pin WIF harness

102512
Deutsch (Grey)

2 Pin WIF harness

102521
Deutsch (Black)

Visit www.davco.com for OEM service part number listing.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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 FUEL PRO® 382
Te c h n o l o g y, L L C TECHNICAL MANUAL

WARRANTY AND CUSTOMER SERVICE

LIMITED PRODUCT WARRANTY
Fuel Pro 482, Fuel Pro 382, Diesel Pro 243, Industrial Pro, Shop Pro, Pro-Chek, Sea Pro and REN Products
DAVCO Technology, LLC warrants these product lines to be free of defects in material and workmanship for 5-years,
500,000 miles or 10,000 hours (whichever comes first) and electrical parts for 2-years, 200,000 or 4,000 hours (whichever
comes first) from the purchase date.*
EyeMax, Electronic Gauges, Electronic Dipsticks, Fuel Pro 384**
DAVCO Technology, LLC warrants these products to be free of defects in material and workmanship for 2-years or
200,000 miles (whichever comes first) from the purchase date.*
In the event of a defective product, DAVCO will either rework the defective product or replace it.
Note: Shop Pro Motor has a one year warranty from the date of purchase.
Limitation:
• DAVCO is not responsible for failures resulting from misuse, misapplication, faulty installation, alteration, poor
maintenance, neglect or accident.
• DAVCO does not warranty any aftermarket or OEM part or product not approved specifically to work with a
DAVCO manufactured product.
• DAVCO is not responsible for downtime, loss of profits or income, living expenses, or other incidental, special
or consequential damages.
• This warranty is the sole warranty made by DAVCO. DAVCO makes no other warranties, expressed or implied,
of merchantability or fitness for a particular purpose.
• Service parts are not warranted.
If you feel you have a warrantable issue, contact DAVCO at 800-328-2611 for a Return Goods Authorization (RGA) Num-
ber. An RGA number is required prior to the return of any product.
* Purchase Date Definitions: The date a new truck (OEM piece of equipment) is purchased by the first retail purchaser
from the OEM Dealer or the Factory. For “Over the Counter” purchases: The date the DAVCO product is purchased by
the first retail purchaser.
**Fuel Pro 384 products are warranted when used in an application containing not more than 20% of ASTM spec bio-
diesel blend stock.
DAVCO Technology, LLC reserves the right to modify this document without notice.

PARTS RETURN GENERAL POLICY

Note: A Return Goods Authorization (RGA) must be obtained from DAVCO prior to returning any products. Returns may
be accepted under the following circumstances:
Order Shipping Error: A credit against the original invoice, including freight charges for both ways will be issued for re-
turns in which DAVCO inadvertently shipped incorrect quantity or product.
Overstock: Returns for ordering more product(s) than required, or incorrect part(s), will be accepted within 60 days from
the date of purchase. Proof of purchase will be required, IE: original invoice/delivery receipt. These types of return(s) are
subject to a minimum restock fee of 40% or $40.00, whichever is higher. Additional restock fees may apply. Product(s)
will be inspected for “like new” condition and additional costs will be the responsibility of the customer. No obsolete
parts may be returned.
Freight charges for return(s) will be the responsibility of the customer.

DAVCO Technology, LLC P. O. Box 487 Saline, MI 48176 Call 800-328-2611 www.davco.com F1271
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