TB9804

S.T.M. TECHNICAL BULLETIN

HISTORY: Delco Remy America and Detroit Diesel have recognized and are attempting to remedy aproblem concerning the Detroit Sixty Series Engines. According to a service bulletin published by the twomanufacturers the Detroit engine produces a harmonic vibration. If the vibration to the alternator is severeand constant, "structural and electrical malfunctions may occur." Delco has made different attempts tocounteract this problem including a bracket bolted on to the popular 30SI alternator to reduce the vibration.The more permanent version of this is the 34SI alternator which has a "quadramount" frame design. Atthis time we have not done any long term testing of the 34SI alternator.

EFFECT: The vibration that is created is more than most alternators can endure. Problems includealternator separation (at the cases), rectifier failure due to semiconductor failure, and brush failure. Somealternators are more resilient than others due to design characteristics. Our JB and 30SI series alternatorsseem to be particularly affected while the 21SI (having limited long term testing) seem to be moreresilient.

SOLUTION: We have found one alternator that is both reasonably priced and is holding up very wellunder the vibration. Here are some of the reasons it makes the distance;

ˆ Double Ball Bearing Designˆ Alternator Case Bolts Are Much Largerˆ Diodes are Built to Tolerate Motionˆ130 Amp. Output

OTHER BENEFITS INCLUDE;ˆ100% New Constructionˆ 18 Month Nation Wide Warranty

IF YOUR COMPANY IS SELLING TO USERS OF THE DETROIT SIXTY SERIES ENGINES, YOUSHOULD SUPPLY THEM WITH THIS ALTERNATOR!!

PART# DT130N

WHAT YOU NEED

TO KNOW ABOUT

THIS IS . . . .

TB9805

S.T.M. TECHNICAL BULLETIN

12 Volt Charging/24 Volt Starting Systems ExplainedBackround-Manufacturers designed electrical systems with 24 volt starting and 12 volt operating voltage.

This takes advantage of the better starting properties of the 24 volt system while retaining the advantage of having 12 volt accessories. This does pose some techinical difficultlys

Some of these create more problems than they resolve. In this bulletin will examine the following items;1) Theory Behind Batteries in Series and Parrallel1) Series Parallel Switches2) Transfomer Style Systems3) Eliminating 12-24 Volt Systems

Theories

1) Inorder to achive 24 volts one battery must beisolated from ground.

2) Cold cranking amperes on batteries in parallelare added to achieve total C.C.A..

3) C.C.A. on batteris in series is an average of all the batteries C.C.A..

1) Contactor Connection2) Contactor Connection3) Relay Contact for Charging Circut4) Starter Solenoid Activator5) Relay Contactor for Charging Circut 6) Coil Grounding Circut7) Coil Energizing Circut (Ignition Switch)8) Starter Solenoid Coil Grounding Circut9) Starter Solenoid Energizing Circut 10) Starter Solenoid Motor Terminal11) Starter Solenoid Battery Terminal

Principles of Operation

11158451) When the series-parallel switch is engaged (with current from the ignition switch to #7) a circut is completed

between #1 and #2. This allows the series circut to be completed and the starter is supplied with 24volts.2) When the series-parallel switch is engaged the circut between #4 and #5 is completed. This gives the starter

solenoid the current (24 volts) to engage the drive and start to crank. 3) When the series-parallel switch is at rest (charging mode) #1 and #2 are open, a circut is completed between

#1 and #3 (completing the ground circut), a circut is completed between #2 and #5 (completing the positive circut)

1115844 1) When the series-parallel switch is engaged (with current from the ignition switch to #7) a circut is completed

between #1 and #2. This allows the series circut to be completed and the starter is supplied with 24 voltsand will crank immediately after.

2) When the series-parallel switch is at rest (charging mode) #1 and #2 are open, a circut is completed between#2 and #13 (completing the ground circut), a circut is completed between #1 and #12 (completing the positive circut)

� � � �

Principles Of Operation

11198451) When the series-parallel switch is engaged (with current from the start(ignition) switch to #7) a circuit is

completed between #1 and #2. This allows the series circuit to be completed and the starter is supplied 24 volts. At the same time a circuit between #4 and #5 is completed. This gives the starter solenoid the current (24 volts) to engage the drive and the starter will begin to crank.

2) When the series-parallel switch is at rest (charging mode) #1 and #2 are open, a circuit is completedbetween

#1 and #3 (completing the parallel ground circuit), a circuit is completed between #2 and #5 (completingthe parallel positive circuit)

11198441) When the series-parallel switch is engaged (with current from the ignition switch to #7)

a circuit is completed between #1 and #2 and acircuit is completed between #12 and #13.This allows the series circuit to be completed,the starter is supplied with 24 volts and will crank immediately thereafter.

2) When the series-parallel switch is at rest (charging mode) #1 and #2 are open as are #12 and #13, a circuit is completed between #2 and #13 (completing the parallel ground circuit), a circuit

is completed between #1 and #12 (completing the parallel positive circut)

TB9805

S.T.M. TECHNICAL BULLETIN12 Volt Charging/24 Volt Starting Systems Explained

1119845

Background: Manufacturers designed electrical systems with 24 volt starting and 12 volt operating voltage. This takes advantage of the better starting properties of the 24 volt system while retaining

the advantage of having 12 volt accessories. This does pose some technical difficulties however.In all but the best circumstances these create more problems than they resolve. In this bulletin we will examine the following items;1) Theory Behind Batteries in Series and Parallel2) Series Parallel Switches

Next month we will examine the following related items;1) Transformer Style Systems2) Eliminating 12-24 Volt Systems

Theories

1) In order to achieve 24 volts one battery must be isolated from ground.2) Cold cranking amperes on batteries in parallel are added to achieve total C.C.A..3) C.C.A. on batteries in series is an average of all the batteries C.C.A. (Including dead batteries)

TB9806

S.T.M. TECHNICAL BULLETIN

12/24 Volt Charging-24 Volt Starting Systems ExplainedBackground-Last month we examined 12/24 volt systems utilizing series-parallel switches. This month we

are going to examine a different way these systems have been engineered.Manufacturers designed electrical systems with 24 volt starting and 12 volt operating voltage.

This takes advantage of the better starting properties of the 24 volt system while retaining the advantage of having 12 volt accessories. In this bulletin will examine the following items;1) Transformer Style Systems2) Eliminating 12-24 Volt Systems

ADVANTAGES

With this style system the 12 volt side of the alternator charges battery one, while the 24 voltside charges battery two (as well as battery one)

The starter draws off of the 24 volt side (two batteries in series) while the truck operates off of the 12 volt side.

Two manufacturers have utilized this system. Delco has the 30SI/TR (S.T.M. #3090NTR) andLeece Neville has the 2600JB/TR (S.T.M. part #26105JBTR) This alternator also has circuit breaker protection on the 24 volt leg.

PROBLEMS

Trouble shooting is difficult for mechanics unfamiliar with the system. Often starters are replaced prematurely due to slow cranking whenthe 24 volt portion of the alternator has failedcausing low cranking voltage for the starter.

Eliminating 12-24Volt SystemsBoth of these systems have problems inherent with their design. They are as follows;

On series parallel switches 1) There are several connections that deteriorate over time. Every one of these connections is like a chain and takes the full current of the system. If one connection corrodes it will create a low voltage situation. 2) The parallel part of the system can malfunction not allowing the number 2 battery to charge therefore creating a low voltage situation.3) After replacing the series-parallel switch the system is often assembled with batteries in deteriorated condition causing near immediate failure.

On transformer systems 1) Transformer systems can fail causing slow starting and "parts replacing" due to lack of information known about these systems.

Solution-As the creation of batteries that create more Cold Cranking Amps it is less practical to use these types of systems to start at 24 volts. Replace the 12-24 volt system with a standard 12 volt system with 2 or 4 batteries wired in parallel to achieve a 12 volt system. All that is required is;

1) 12 volt starter-There is a 12 volt version of your 24 volt starter. If you need the appropriate part number please call2) Wiring-The starter wiring must be replaced because of the increase in cranking amperage3) We recommend the batteries be replaced with 2 or 4 matched batteries

Recommended Cables and Their Length Total Cranking

Circuit Length* Cable (in inches) Size

Quad 0400 Single Path Circuit Dual Path Circuit

Quad 0350

Triple 0300

Triple 0250

Double 0200

Single 0150

Dual Path Circuit

Use dual path250

Quad 0200

Triple 0150

Double 0100

*Circuit length includes both positiveS.T.M. Heavy Duty Electric and negative cables measured from (610)967-3810 Fax(610)967-3496 the last battery to the starter.

TB9807

TECHNICAL BULLETIN

42MT STARTER DRIVE END ROTATION

History: Truck manufacturers continue to strive to pack more into less. One of the items effected by this is the space occupied by the starter. On certain applications the starter requires a rotation of 88 degrees instead of the standardly possible 82 degree position.

Solution- Delco Remy accomplished this by creating a drive end which has the mounting holes turned 6 degrees.This is difficult to see however below we have illustrated the difference.

Which part numbers are effected-The following Delco part numbers have the D.E. 8; 1990489, 1990490, 1990491, 1993822, 1993835, 1993945, 10479017, and 10478932.

What does this mean to me- In most circumstances the 82 degree position of the D.E. 1 is sufficient to fit theapplication. In those rare instances when 88 degrees is required then you must use the 42MT starter with a D.E. 8 part number suffix. (i.e. 421211 D.E. 8) It is also possible and more economical to stock just the D.E 8 nose housing.

Drive End #1 Drive End #8

Notice the intersection of the drive end mounting hole at the arrow.You will see a subtle difference between the two noses.

TB9808

TECHNICAL BULLETIN

Delco 22SI Alternator

The new version of the 21SI alternatoris the 22SI. Delco has made severalchanges to improve the longevity oftheir alternator. The following are thechanges made and information on specifications.

Changes made from the design of the 21SI alternator

Physical Changes1) The housings, both drive end and slipring end, have been made more sturdy.2) The thru bolts were increased in size from 10-24 to 1/4-20.3) Series designations (22SI) are clearly cast into the S.R.E..4) The grounding boss has been moved slightly.

Internal Changes1) The brush holder has been engineered from an entirely different principle. Instead of the "swing brush" setup

Delco designed a very long straight brush that has nearly constant brush spring tension throughout its life.2) The diode trio assembly has been changed to lower "turn on" speed and increase reliability.3) Most other internal components are similar to the 21SI alternator.

The Ups and the DownsWe are impressed by the increase in size and strength of the housings and especially thru-bolts. The diode trioseems to be a good item as long as it makes the distance. We were not so impressed by the brush holderassembly as the brushes would seem to stick in a seal created to keep debris out of the brush holder. It seems itis a step in the right direction, we just don't know how far.

S.T.M. Part Numbers22100N -100 AMP. NEG GRD. 12 VOLT S.T.M. REMANUFACTURED22130N -130 AMP. NEG GRD. 12 VOLT S.T.M. REMANUFACTURED22145N -145 AMP. NEG. GRD. 12 VOLT S.T.M. REMANUFACTURED22160N -160 AMP. NEG. GRD. 12 VOLT S.T.M. REMANUFACTURED2250N-24 -50 AMP. NEG. GRD 24 VOLT S.T.M. REMANUFACTURED2270N-24 -70 AMP. NEG. GRD 24 VOLT S.T.M. REMANUFACTURED

22100NX -100 AMP. NEG. GRD. 12 VOLT NEW22130NX -130 AMP. NEG. GRD. 12 VOLT NEW22145NX -145 AMP. NEG. GRD. 12 VOLT NEW22160NX -160 AMP. NEG. GRD. 12 VOLT NEW

TB9809

TECHNICAL BULLETIN

LEECE NEVILLE 7000 SERIESBackground-Leece Neville made the 7000 series alternators to fit specials applications which current alternators

did not fit. These applications include fire engines, ambulances, and tow trucks which are usually Ford vehicles. A large portion of these applications are high amp. draw/high output applications.

Differences-There are several different varieties of the 7000 series alternators, we are currently cataloging over 50 units. The upside of this is that only 2 or 3 of these are popular. These units and theirdifferences are outlined below.

Alternator Number 7601AAˆ "76" prefix of the Leece Neville part number indicates 105 Amp.ˆ "AA" suffix of the Leece Neville part number indicates externally regulatedˆ The "spool" portion of the alternator is 3" in lengthˆ The pivot bolt diameter is 7/16"

` ˆ The rotor shaft diameter is 7/8"ˆ The hold down bolt is only on one side

Alternator Number 7706JAˆ "77" prefix of the Leece Neville part number indicates 165 Amp.ˆ "JA" suffix of the Leece Neville part number indicates internally regulatedˆ The "spool" portion of the alternator is 1" in length

` ˆ The rotor shaft diameter is .669"ˆ The hold down bolt is on both sides of the alternatorˆ The alternator conforms to the usual Leece Neville two wire

hookup (Pos. and Neg.)ˆ The rectifier assemblies and regulators are brand new O.E.M.

components for long lifeˆ To test, hook up the positive and negative leads(from the

battery to the alternator) and start the vehicle. The output should be between 13.5 to 14.5 with the batteries at 90% charge, measured between the positive and negative terminals on the alternator.

TB9809

TECHNICAL BULLETIN

LEECE NEVILLE 7000 SERIESTROUBLE SHOOTING GUIDEAny of the Leece Neville/S.T.M. part numbers that end in "AA" indicate unit that is externally regulated. Thismeans that a good portion of the time that the charging system fails it is the regulator that has failed. When thenew alternator is installed the unit still does not function. The following is a guide to use when troubleshootingthe externally regulated systems.

1) There is a small jumper wire between the negative output terminal and the brush body. Make sure that thejumper is installed and in good shape.

2) There is a wire from the regulator, mounted on the frame, thatattaches here. This wire must also be connected properly

3) As most other Leece Neville alternators the battery cables mustbe hooked up to both the (+) positive and (-) negative.

"EVERY THING LOOKS LIKE ITS HOOKED UP PROPERLY AND YET IT DOES NOT CHARGE."

Bypassing the voltage regulator1) Disconnect the regulator terminal (at arrow #2) and jump between (+) positive and the terminal on the brushholder that the regulator normally connects to(at arrow #2). There should be a small spark. This is a normalcondition. 2) With the engine running the alternator should be charging, however, the alternator will chargeuncontrollably since the voltage regulator is being bypassed. This should only be done to determine thealternator is functioning properly. Extended running will harm or destroy the batteries.3) Under the above condition the alternator with the batteries charged to 90% the alternator should charge morethan 13.5 volts. In the event it does not and you have all the jumpers in place correctly (#1 to negative and #2to the (+) positive) the alternator is defective.

IF YOU HAVE ANY QUESTIONS CALL THE FACTORY ASSISTANCE LINE AT 1-800-353-2243

TB9810

TECHNICAL BULLETIN 37MT STARTER

IDENTIFICATION GUIDEBACKGROUND-There are many 37MT starters that are cataloged, however there are only a handful that are

popular. The two most popular are outlined below. There are different combinations of drives, drive ends, voltages, and thermal overcrank switches that create all the other part numbers. In

the event that Delco Remy has not assigned a remanufactured number, S.T.M. will use the long (new) number.

ˆUNIT PICTURED IS S.T.M. PART # 37-842 (323-842)ˆ12 VOLT -CHASSIS GROUND (NO EXTERNAL GROUND

POSTS OF ANY KIND)ˆNEW O.E.M. 12 TOOTH DRIVEˆDRIVE END #2 (1/2" MOUNTING HOLES)ˆAPPLICATIONS INCLUDE INTERNATIONAL DT 360 + 466

ˆUNIT PICTURED IS S.T.M. PART # 37-840 (323-840)ˆ12 VOLT -CHASSIS GROUND (NO EXTERNAL GROUND

POSTS OF ANY KIND)ˆNEW O.E.M. 10 TOOTH DRIVEˆDRIVE END #5 (NOTICE THESE TWO MOUNTING BOLTS

CUT INTO THE HOUSINGˆAPPLICATIONS INCLUDE FORD 6.6 +7.8 L. AND CARGO STAR

OTHER IMPORTANT FEATURES

IF YOU HAVE ANY QUESTIONS CALL THE FACTORY ASSISTANCE LINE AT 1-800-353-2243

1993866GROUND STUDAND OVERCRANKPROTECTION ARE ON THE BACK

10478890GROUND STUD LOCATED IN THE"NORMAL" POSITION

37-818 (323-818)NOTICE GROUND STUD ON FIELD FRAME

TB9811

TECHNICAL BULLETINREMANUFACTURED 37MT

STARTER FEATURES FROM S.T.M.

Units Are Tested to Meet or Exceed Delco Specifications Every Time

IF YOU HAVE ANY QUESTIONS CALL THE FACTORY ASSISTANCE LINE AT 1-800-353-2243

Unit Noses are Properly Rotatedand Torqued for

Immediate Installation

100% of the Solenoid Coils are Removed and Inspected or Rewoundto O.E.M. Specifications

100% New Contactsand All New Contact

Disk With Anti-Fungual Coating

100% New Brushesand Sintered

Bronze Bushings

100% of the Field Coilsare Removed and

Varnished or ReplacedWith New

Starter Drive is Replaced100% With New

Drive For Increased Longevity

Drive Retaining Collar and Clip are Both

Repalced With NewDelco Components

Every Time

Armature Shaftsare 100%

Replaced W/Newand Armaturesare Varnish

B a k e d

TB9901

S.T.M. TECHNICAL BULLETIN

Split Battery Systems

History-Truck batteries become discharged if the driver uses them to provide power to the accessories while thetruck is not producing current (The truck has been shut off).

Effect-This does not allow enough current in the battery to start the vehicle thus causing an expensive delayuntil restart. Low battery voltage starting is also very hard on the starter and may lead to premature starterfailure.

Solution-Some truck manufacturers have isolated one of the four batteries to power the engine off loads. Thisallows three fully charged batteries to start the truck even if the fourth battery has been fully discharged.

Details- The fourth battery in the system is isolated from the rest of the batteries by a magnetic switch. Theswitch is activated when the alternator produces current(when the truck is running) thus allowing the fourthbattery to be recharged during the normal use of the truck.

S.T.M. Heavy Duty Electric 7601 Chestnut St. Zionsville, PA 18092 1-800-353-2243 (610)967-3810 Fax(610)967-3496

TB9902

TECHNICAL BULLETIN

Delco 28MT Starters There are many 28MT starters in our catalog. The following are

some of the more popular of these starters.

S.T.M. # 28-447 Pictured S.T.M. # 28-419 Pictured 12 Volt 24 Volt 12 Volt 10 Tooth Drive 10 Tooth Drive 10 Tooth Drive

Delco # 1113276 S.T.M. # 28-447 S.T.M. # 10479611 Fits Ford and Cummins Delco # 1113266,267,269, Delco # 10479611

270,295,296 Fits Military 6.2.L Fits 6.2 + 6.5L. G.M.C. .

S.T.M. # 28-451 Pictured 12 Volt 12 Tooth Drive S.T.M. # 10479614 Pictured Delco #1113273 12 Volt 10 Tooth Drive

Fits Clark, New Holland, Hyster, Fits Ford Trucks Bobcat, and Perkins

S.T.M. Heavy Duty Electric 7601 Chestnut St. Zionsville, PA 18092 1-800-353-2243

TB9902

TECHNICAL BULLETIN

Delco 28MT Starters Continued .

S.T.M. # 1113271 Pictured S.T.M. # 28-482 Pictured 12 Volt 24 Volt 12 Volt 10 Tooth Drive 10 Tooth Drive 10 Tooth Drive

Delco # 1113289 S.T.M. # 1113271 S.T.M. # 1113272Fits Mack Midliner Delco # 1113271 Delco # 1113272 Fits John Deere Fits John Deere

S.T.M. #10479615 Pictured12 Volt 10 Tooth DriveDelco #10479615 and 10479618Fits Blue Bird Bus and Ford Truck

S.T.M. Heavy Duty Electric 7601 Chestnut St. Zionsville, PA 18092 1-800-353-2243