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Those of you who come here from elsewhere other than the yahoogroup, we were a yahoo email list of about 1300 people before we set up this forum. There are excellent files/photos/links all on the yahoo group. Here are the links!

Files: PDF versions of manuals, 4BT dimensions, power output, fuel economy specs, etc.

Photos: Photos of 4BTs in different vehicles, air intake and exhaust manifold setups, modified 4BTs, cleaned up and painted 4BTs, etc.

Links: Conversion parts sources, etc -

ALSO -- BIG THANKS TO BOBS (Moderator) who compiles all of the info for this thread...
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180 Posts
Ok where can we get a manual or specs ?

140 bucks for a manual up here in Canada , there has to be some cheaper sources for manuals or specs out there.
Cummins should sell a CD for 20 bucks and not a cent higher. We also need a source for bearings and gaskets and water pumps and alternators besides cummins.


EDITED to add the answer:
Cummins Service Publications

Premium Member
1989 Jeep Wagoneer, 360v8, 727, stock for now,
2,967 Posts
FAQ: Commonly Asked Questions, 4BT Files, Photos, Links, Etc....

original post by fly71h on Yahoo 4BT site;

"The primary difference between an on road and off road engine is the function of the governer. The on road engine has what is sometimes referred to as a speed governer, which does exactly what the name implies. It limits the maximum rpm of the engine and nothing else. Actual engine speed (below max) is controlled by the throttle linkage on the injection pump. If the load on the engine increases, rpm will decrease unless the throttle is opened further by some outside influence. In the case of a truck engine, that influence would be the driver's foot. The off road engine has a load governer. It's purpose is to keep the engine at a specified rpm regardless of load. As load increases or decreases, the governer proportionally increases or decreases fuel delivery to maintain the same rpm without any movement of the throttle. What this means is, when your truck with the off road engine in it encounters a hill, it is going to try to go faster all by itself. I'm not saying it won't work, but it will be very "different" to drive, and could potentially be dangerous under certain circumstances.

original post by Bob Sova on Yahoo 4BT site;

"I agree with you and could not have said it better. You have perfectly described a "industrial stationary engine" in a power unit such as a pump or generator. They are designed to run at a fixed speed to prevent cavitations in the pump or to maintain the hertz frequency in a generator. There are however some non-stationary off road diesel engines that could possibly be adapted to function in vehicles. These would be found in wheeled and tracked tractors. These engines are designed to be run at variable throttle position speeds and the governor is designed to increase and maintain the engine speed only as far as the throttle is positioned. The major difficulty in using one of these engines would be emission certification requirements that our duly elected officials have established for our own protection."

The other giveaway is the on road Diesel will have a EPA tag stating approved for on road use


5,053 Posts
FAQ: B Series Engine Torque Values

Here are some of the needed torque values for the 4BT in FT/LB's unless otherwise indicated:

Bracket, rear, engine lifting ---------------------57
Connecting rod---------------------------------26, then 52, then 74
Crankshaft damper & pulley---------------------92
Exhaust manifold to head-----------------------32
Flywheel adapter housing, Aluminum-------------44
Flywheel adapter housing, Iron------------------57
Flywheel housing cover [bellhousing to adapter]---18 to 20 Use clean plated bolts; lube threads with oil or Permatex blue silicone sealer
Flywheel to crankshaft-------------------------101
Gear housing timing cover-----------------------18
Head Bolts.............See below;
Injector retaining nut---------------------------44
Injector fuel drain banjo screw (in injector)-------72 in-lb
Intake manifold cover---------------------------18
Intake jacket water aftercooler to head----------18
Main Bearing------------------------------------44, then 88, then 129
Oil Pan------------------------------------------18
Rear seal mounting cover------------------------48 INCH/LBS
Rocker arm support------------------------------18
Transfer pump mounting--------------------------18
Turbo to manifold--------------------------------33
Valve cover-------------------------------------18
VE Bosch injection pump:
Solenoid, fuel shut off---------------------32
Solenoid, KSB-----------------------------16

Cylinder Head Bolt Torque:

Cylinder Head Capscrew Torque Manual (722 KB)
Head torque ? and updated at
More head torque confusion

ALSO SEE: For GENERAL TORQUE SPECIFICATIONS by thread size and material and from - Cummins 1991 (and after) B-series engine Torque Specifications .

Clutch Cover AKA Pressure Plate:

Tighten cover bolts a few threads at a time. Cover bolts must be tightened evenly and to specified torque to avoid distorting cover.

Tighten 5/16" diameter bolts to 17 ft/lb [23 N.m]
Tighten 3/8" diameter bolts to 30 ft/lb [41 N.m]
REF: 1992 Dodge RWD D&W 150-350 truck service manual pg. 6-12 published by Chrysler Corp.

Note: The flywheel adapter housing is what we commonly refer to as a Chevy, Dodge, Ford, or SAE adapter.
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Discussion Starter · #5 ·

5,053 Posts
So where can I find a stepvan with a Cummins 4BT engine?

Check every few weeks at: for the latest "Transportation Auction" listings. Click on the transportation auction listed on the center of the page under Global Auctions Calendar. The individual listings will the be on the right side of the page under "LOT CATALOG"

Additional DoveBid purchasing information discussed in:

Also note prohibited threads on ongoing auction price fixing discussions:

4BT Sources, Where were 4BT installed: <=P30 18' Stepvan Dimensions

5,053 Posts
Misc. Common Part Numbers for P20 & P30 4BT's

From my notes as removed from various stepvans and postings here on 4BT Swaps:

Air filter - Fleetguard AH-1107 used on the 4BT P30 Stepvan
Barring Tool Hole cover - consists of Cummins#'s - Plug, O-ring-3910248 & Seal, O-ring-3910260

Belt & Fan:
Belt Tensioner, CPL 858, Cummins part# 3934823,, also see and for more info
The Gates 38513 is the right part # for the CPL 857 & CPL 858 too.

Block Heater
, engine coolant, replacement with power cord - NAPA- Balkamp #605-1575

Bracket, Throttle cable mounting, P30 w/4BT VE pump, mounts to rear IP mounting brace - Cummins 3910121

Dipstick: <=Part# for shorty dipstick

Engine mounts, rubber isolators - Anchor #2710, same mounts as used on Dodge Cummins diesels from 1989-1993
Eliminator, oil filler plug on timing cover - Cummins 3903463
Fan bearing, 1989-1993 Dodge Cummins fan set up, DF0766LUA
Flywheel mounting bolts, Manual transmission - Cummins 3901395, 8 required
Freeze plugs, soft plugs, engine block - Cummins 3922072
Fuel filter, no water drain - Fleetguard FF-5052
Fuel Heater Gasket:
for bio-diesel:3958485-s
NAPA:1036(This filter gasket will work but thicker; buy the filter and only use the gasket) These numbers may also work for the dual filter to head seal

Fuel pump [AKA feed pump & lift pump] DIAPHRAGM TYPE, non Cummins replacement, part number Delphi HFP274, for use with Bosch VE Pump, available at: and
Other manufacturers part numbers at :
Airtex 1407
Carter M73060

Fuel Pump, electric, 8 psi @ 100 gph, Carter CRT-P4600HP, 3/8" female NPT threads ( Use with lift pump block off cover plate - Cummins Part # 3863441 (or use a Chevy V8 block off plate)

Fuel pump [AKA lift pump] installation parts, low pressure piston type for use with Bosch VE Pump:
  • Cummins Part # 3936320 lift pump (qty 1 )
  • # 3914753 Fuel Line (qty 1)
  • # 3931348 Gasket (qty 2)
  • # 3918191 Seals (qty 2)
  • # 3914284 Spacer (qty1)

Fuel Tank Replacements:


Gasket, cylinder head, CPL 858, 1268, Cummins part numbers:
3917353 Standard
3915720 .15mm oversize
3915721 .50mm oversize
From Case Tractor:
Change the first 3 to a J
J917353 Standard
J915720 .15mm
J915721 .50mm
Others available:
Fel-Pro head set #FP3804896, Fel-Pro head gasket only #FP3283569
Victor head set #HS4691, Victor head gasket only #4691

Gasket Sets, 4BT Other Sources (NON-Cummins):

Exhaust manifold to head gaskets Mopar part #4796511
Turbo to exhaust manifold gasket Mopar part #4429357
Turbo drain flange gasket Mopar part #5003332AC

Grid Heater Relays Used on 1st Gen Dodges:

Mouser Part #: 802-120-901
Manufacturer Part #: 120-901
Manufacturer: Stancor

Description: General Purpose / Industrial Relays SPNO 12VDC, Stancor TYPE 120
Price (2010 in USD) $16.64
Silverlight Page 1,967, Mouser Enhanced Catalog
Supplier: Mouser
1. If the above links fail then search for 120-901 at or google "stancor 120-901"

2. Requires 2 relays, ONE per grid element

Hose, Clamps, Tubing, sources:


Bosch Type A Pump info: <=Isuzu info

Bosch Fuel Injection Publications:
Bosh VE Pumps Manual (1.6 MB)
Injection pump seal kit, VE rotary pump, Bosch DGK-121 also see: and for complete kits.
The 4 cyl. Bosch VE kit # is DGK126. The 6 cyl. Bosch VE kit # is DGK121 REF:

Exploded views and parts catalog listing can be viewed at: (Note that the link for the dpe30125.pdf document at is DEAD!! Might try Googling dpe30125.pdf for possible other reliable sources.)
And the 6BT at:

Description and theory & operation (How it works) available at: and same at:

Diesel Distributor Fuel Injection Pumps - VE:

Bosch VE type injection pump part numbers to Cummins CPL:

3917530 1986-90 VE Series Rotary, CPL 858, 105 HP 4BT
3908191 1986-90 VE Series Rotary, CPL 767, 105 HP 4BT
3917535 1986-90 VE Series Rotary, CPL 857, 120 HP 4BT
3906631 1986-90 VE Series Rotary, CPL 593, 105 HP 4BT
3919716 1991-93 VE Series Rotary, CPL 1260, 105 HP 4BT
3926831 1991-93 VE Series Rotary, CPL 986 & 1848, 120 HP 4BT

Dismantle & reassemble pic at: and 6BT at This is for the VW version which is 90% the same. VE Governor spring install

Injection Pump "full power screw" Bosch part number: 1-463-402-423(-000) & priced around $20. Also see:

Injection pump removal & installation video (includes Dodge-Bosch VE 6BT warranty info) Part 1: and Part 2: and Part 3: <=Fuel system troubleshooting

Resealing a Bosch VE Injection Pump: <=VW Bosch head seal to body replacement instructions

Bosch VE Governor Cutaway:

Bosch P-PUMP Performance Troubleshooting:

HPCR Dodge Cummins Common Rail Diesel Injection Systems: <=Description & operation

Bosch Injector:
VE type return line sealing washer, U shaped double washer, Chrysler part# 4429380 AB
Return Line Copper Washers is the same for 6BT and 4BT - Cummins #3903380
The complete 4BT Fuel Injection Return Line Manifold is Cummins P/N 3909695

CPL 593 injector info:
9mm Injector Assy is: 3909509
--Nozzle: 3905436

Per Cummins, 7mm replacement has superseded the 9mm: 3919345.

The adapter sleeve for 7mm tips into a 9mm head is 3919358.

Cummins CPL 857 4BTA With JWAC Injection line part numbers; see:

Bosch VE injection pump woodruff key part number: 1460023307

Bosch VE Governor Spring Part Numbers:
2800 RPM 1-464-650-386
3200 RPM 1-464-650-366
3800 RPM 1-464-650-374
4200 RPM 1-464-650-354

Current part numbers used in December 2009. Use at your own risk. Available through your local Bosch Pump Shop and some Cummins dealers. Also note: The RPM is the set defueling point of the injection pump and NOT the maximum RPM attainable. The maximum RPM can vary in excess of the defueling point based on your pump adjustments. Past heavy fueling cases have been reported to result in 200 to 400 RPM's past the governor spring's defueling set point. Ref: DTR,, & 4BT Swaps forums.

Bosch VW Injector Pump Governor Operation: VW but same principles

VE Pump Shaft Machining:

Cummins 4BT Intake Cover for use with CAC:
Intake cover for a 4BTA 120 hp PN# 3921500 for use with grid heaters.

Cummins 12-Valve Fuel System Troubleshooting:

5.9 I6 Cummins 24-Valve Diesel Engine:

Oil Pressure Regulator Gasket Source:

P30 Engine & Chassis Replacement Parts; Clutch, Transmission, Mounts, Flexplates, Brakes, Springs, Engine rubber mount cushions, etc Catalog.pdf

Power steering pump, (pump only, no mounting bracket) 1989 4BT, Cardone 208709 possibly updated to Cardone 20-860

Power steering pump, (pump only) 1992-1993 Dodge Cummins replacement, Cardone 208001

Publications, Cummins, Manuals, Operation, Maintenance, Service, Troubleshooting, Parts:
Manuals, service, operation, etc website: Cummins Service Publications <=Online parts catalog
The CUMMINS part number for the 4b INDUSTRIAL parts catalog is 3884232.
Also check: for used & out of print. Search using the word: cummins
NOTE: Prices there vary from dirt cheap to extremely outrageous.

Pulley, Delco alternator, 2.625" od x 1.750" deep - Cummins 3909361

Radiator hose, bottom, one piece - Carquest 21731 replacement used on P30 Stepvans
Radiator hose, top, one piece - Carquest 21729 replacement used on P30 Stepvans
Also see: for additional rad hose part numbers

Radiator outlet-upper, thermostat housing:
Points straight up - Cummins 3285102 (replaces 3903756) also see 3914409
Points forward toward rad - 3914414, 4BT P30, Also see
Points toward drivers side (USA) - 3920353, 92 & 93 Dodge Cummins 6BT, with IC
Points toward passenger side (USA) - ???????, 89 to early 91 Dodge Cummins 6BT, without IC

Radiator inlet-lower hose:
Points straight outward - Cummins part #3916625

Radiator and Coolant Machined Hose SIZE Adapters: for radiator hose reducers;

Starter spacer, 16 mm thick, P30, Cummins 3906647

CNH [Case-New Holland]part number 47616858

Thermostat Replacement with Dodge Part Numbers:
Thermostat housing gasket:
Cummins 392020; Fel-Pro 35526

Timing Cover Oil Filler Plug & Gasket: <=Timing Gear Cover Plug Part#

TURBO Master OEM Application Information. AKA: What's this turbo part number fit:

4" 6BT Cobrahead Exhaust Head Elbow, short bend points down
Cummins Part Number:
Elbow # 3921534 (OLD)
Elbow # 3927862 (NEW)

Found on 8.3 Cummins in ford, freight, RV, Rear Engine Bus

Valve cover with oil filler consists of:
  • Cummins 3928405 (replaces 3902605) valve cover;
  • Cummins 3901895 cap;
  • Cummins 3936876 seal

The following part numbers are found in the Ford 4BT automatic transmission vans. Info from the Yahoo 4BT group. I have no additional information:

Adapter - 3912601 FH9043
Flexplate - 3918957
Clamping ring - 3904361
Crank adapter, (hub?) - 3907620
Torq converter adapter - 3907619
Flywheel Ring Gear # 3905909

The following part numbers are found in the GM TH400/475 4BT automatic transmission vans. I have no additional information:
Flexplate 3918957
Spacer 3907701
Clamping ring 3904361
Wave ring 3908124

Note: Cummins referenced part numbers are frequently updated by Cummins so these listed numbers may only provide a starting point for cross referencing.

Cummins Engine Part Numbers to Case Tractor Part Number Conversion System:
Use the Cummins part #'s. Just change the first "3" to a "J"

So as an example Cummins part# 3928405 becomes Case Tractor part# J928405
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5,053 Posts
Misc. External Links to Parts, Donor Vehicles,Recipiant Vehicles, Online Auctions etc

Not in any specific order:

Government, Local, State, Federal:
Also check your state's website for online and public auctions of surplus equipment and vehicles.

Public Auction Government and Others:

Online Retail Sales:

853 Posts
Wix oil filter 51602
Fleetguard oil filter - LF3345
Napa Gold oil filter - 1602

Wix fuel filter - 33472
Napa fuel filter -3472

Stock-style rubber motor mounts used in Ford chassis vans is Anchor 2469.
Rock auto has them for $2.67, for $7.97, Advance Auto Parts for $7.97
The are the mounts used in '80 Dodge vans and trucks with gas engines.

5,053 Posts

5,053 Posts
How Much Does a 4BT Conversion Cost?

There are many variables involved but generally plan on spending as much as twice your minimum budget before you are done:

Also read this information from "The U.S. Environmental Protection Agency" BEFORE you start:

5,053 Posts
STARTERS: Dodge Cummins 6BT Series Part Numbers

Starter part number cross reference information for folks using Dodge Cummins engines, adapter plates, flywheel housings and etc:

Cummins 3912084
Denso 128000-4910
Lester 17215

Cummins 3921682
Denso 228000-2290
Lester 17548

Cummins 4090084
Denso 428000-1190
Lester 17892

Lester is generally the standard interchange reference number between various manufacturers. Cummins part numbers are generally the most expensive and are subject to frequent change. Denso is the OEM in most cases.

5,053 Posts
Brakes, Hydroboost, Hydraboost, Applications & General Information <=Parts & pictures <=Parts suppliers <=79 Dodge factory replacement hydroboost part# <=82-86 GM truck factory replacement hydroboost part# <=81-85 GM passenger car factory hydroboost part# <=Hydraboost parts & rebuild kits <=hydroboost problems, self applying brakes without touching the pedal <=Hydroboost issues

Brakes, Setups, Sizing and General Information: <=Air brake compressors <=Vacuum booster type<=Sizing <=Hydraboost problems & Tech Forum Link <=Using the step van booster <=Hydroboost and REMOTE MASTER CYLINDER RESERVOIRS <= Setting proper Hydroboost pushrod length

Brakes (& Clutch) Relining Services:<=Antique, Classic, Industrial, Obsolete linings

Brakes, Technical Assistance:

500 Posts
FAQ: Commonly Asked Questions, 4BT Files, Photos, Links, Etc....

From over at the TDR site, a few P/N's that we might find useful. These are for the ISBe 3.9/4.5L I think.

(170hp, 3.9L) can be flipped end-for-end for front or rear sump (SWEET! ).

Here are some part numbers I managed to get...
Cummins part # (as of 2/8/06):
4897997 OEM oil pan
4896964 oil pickup tube for REAR sump
4898301 oil pickup tube gasket
4897887 oil pan gasket

5,053 Posts
Calculators, Gear, MPH, KPH, Tire Size, Crawl Ratio, Metric to US, Dollar Conversions

Calculators, Gear, Tire Size, Crawl Ratio: <=XLS format down loadable <=From the folks at Cummins <=gear ratio calc shows aux trans ratios!

Metric Units of Measure Conversions:

Engineering Fundamentals Design Standards Homepage-Sheet metal thickness Gauge# to thickness in inches, Threads, Sensors, O-Rings, Gears, etc:

US Dollar to 164 Other World Currencies:

Inflation Calculator
The following form adjusts any given amount of money for inflation, according to the Consumer Price Index, from 1800 to 2007. Enjoy! <=US Government sourced

384 Posts
I have a link that you can download the 4bt manuals in .PDF format.

Password: 4bt

There are two types of Engine Parts Manuals and one Service Manual.

I think that rapid share has a limit on how much you can download for free. You can pay like $6 and get a 24 hour pass to download all you want.
Yes, you have to wait 23 minutes after every single download, if you're downloading free.

74 Posts
Since we have the torque specs, here is a mostly complete list of the fasteners used on our B series engines that the torque applies to..
This list is riped from a 6BT manual, so some quanities (oil pan bolts, injector line mounts) will be difrent, adjust as needed.

If you know of something that is inacurate, or have bolts to add, send me a PM and I will update it


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