REPOR T RESUMES - ERIC

1 REPOR TRESUMESED 021 078VT 005 661 AUTOMOTIVE diesel MAINTENANCE 1. unit VII, ENGINETUNE-UP-- detroit diesel ENGINEERING INSTITUTE, CLEVELAND, OHIOREPORT NUMBER PTAM-1-7 PUB DATE 11 OCT 65 EDRS PRICEMF-$ $ *STUDY GUIDES, *TEACHING GUIDES, *TRADE ANDINDUSTRIAL EDUCATION, *AUTO MECHANICS (OCCUPATION), *DIESELENGINES, ADULT VOCATIONAL EDUCATION, TRANSPARENCIES,PROGRAMED MATERIALS, INDIVIDUAL INSTRUCTION, INSTRUCTPOWALFILMS, PROGRAMED INSTRUCTION, MOTOR VEHICLES, EQUFNENTMAINTENANCE,THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOPAN UNDERSTANDING OF TUNE-UP PROCEDURES FOR diesel ARE SCHEDULING TUNE-UPS, AND TUNE-UP PROCEDURES. THEMODULE CONSISTS OF A SELF - INSTRUCTIONAL BRANCH PROGRAMEDTRAINING FILM "ENGINE TUNE-UP-- detroit diesel ENGINE" ANDOTHER MATERIALS. SEE VT 005 655 FOR FURTHER IN THIS SERIES ARE AVAILABLE AS VT 005 655 - VT 005684.

2 MODULES FOR "AUTOMOTIE diesel MAINTENANCE 2" AREAVAILABLE AS VT 005 685 - VT 005 709. THE 2-YEAR PROGRAMOUTLINE FOR "AUTOMOTIVE diesel MAINTENANCE 1 AND 2" ISAVAILABLE AS VT 006 006. THE TEXT MATERIAL, TRANSPARENCIES,PROGRAMED TRAINING FILM, AND THE ELECTRONIC TUTOR MAY (FOR $ PER WEEK) OR PURCHASED FROM THE HUMANENGINEERING INSTITUTE, HEADQUARTERS AND DEVELOPMENT CENTERS2341 CARNEGIE AVENUE, CLEVELAND, OHIO 44115.(HC)STUDY AND READINGMATERIALSAUTOMOTIVEMAI/ ENGINE TUNE-UP:DETROITDIESEL ENGINESECTION ASECTION BCETABLE OF CONTENTSUNIT VIISCHEDULING TUNE-UPSTUNE-UP DEPARTMENT OFHI ALTH, EDUCATION& WELFAREOFFICE Of EDUCATIONTHIS DOCUMENT HASBEEN REPRODUCEDEXACTLY AS RECEIVEDFROM THEPERSON OR ORGANIZATIONORIGINATING OF VIEW OROPINIONSSTATED DO NOTNECESSARILY REPRI SENTOFFICIAL OFFICE OfEDUCATIONPOSITION OR 1-710/11/65(HUMAN ENGINEERING INSTITUTE4 PTAM 1-7 SECTION A--SCHEDULING "fUNE-UPSIn previous units we have covered the basic components of both the inline71 and the Vee-71 series detroit diesel Engines.)

3 By this time we know aninjector from a governor, a valve from a crankshaft, etc. We have beensubjected to the four flows in the diesel :air, water, fuel, and oil. We knowhow the components of each flow operate and function, and how each one isdependent on the other for maximum engine efficiency and there are numerous combinations of engines and types of governors,(i. with a limiting speed single or double weight; inline withvariable speed; Vee with a limiting speed etc. ), this unit will cover thestep by step procedures for tuning an inline series with a limiting speedgovernor and a Vee series with a limiting speed governor. Check yourmaintenance manual for the difference in steps and readings necessary totune the other combinations you may be working , it is important to know when an engine tune-up is engines, regardless of type should be tuned-up new engine is new engine has run 100 hours, or 300 is engine has just been cylinder head assembly has been mechanical engine governors, as mentioned before, are identified bya nameplate attached to the governor instance letters D.

4 W. L. the governor as being a double weight, limiting speed weight, variable speed would be stamped S. W. V. , when performing a tune-up on an engine in service, it is onlynecessary to check the various adjustments for a possible change in , if the cylinder head, governor, or injectors have beenreplaced or overhauled, then certain preliminary adjustments are requiredbefore the engine is BTUNE-UP PROCEDURESThe preliminary adjustments consist of thefirst four items in the tune-upsequence as outlined procedures are the sameexcept that thevalve clearance is greater for a cold engine.(Refer to your maintenancemanual for this information. )To tune-up an engine completely, all of theadjustments, except the valvebridge adjustment on four valve cylinder heads, aremade by following thetune-up sequertce given below, after the engine hasreached the normaloperating the adjustments are normally madewhilethe engine is stopped, it may be necessary to runthe engine betweenadjustments to maintain normal operating : The exhaust valve bridges on thefour valve cylinder head areadjusted at the time the cylinder head isinstalled on the engine and, untilwear occurs, no furtheradjustment is required.

5 When wear isevident,perform a complete valve tune-up procedures apply to thindividual engines of multiple engineunits as well as to the single , the throttle linkageof multiple engine units must beadjusted after the individual engines havebeen is extremely important thatthe following tune-up steps be followedinsequence:Tune-up Sequence for the exhaust valve the fuel the governor the injector rack control the maximum no-load the idle the buffer the linkage and throttle 17 PERFORMING STEP No. 1-- EXHAUST VALVE CLEARANCE NOTE: unless specified the same procedure is used on the inlineseries as on the Vee correct exhaust valve clearance at normal engine operating temperatureis important for smooth, efficient operation of the valve clearance can result in loss of ^,ompression, misfiringcylinders, and- eventually - burned valve seats and valve seat valve clearance will result in noisy operation, especially in thelow speed the cylinder head is overhauled, the exhaust valves are recon-ditioned or replaced, or the valve operating mechanism is replaced ordisturbed in any way.

6 The valve clearance must first be adjusted to thecold setting to allow for normal expansion of the engine parts during theengine warm-up will insure a valve setting that As closeenough to the specified clearance to prevent damage to the valves whenthe engine is Exhaust Valve Adjustment on Engines with Two ValveCylinder Heads--The exhaust valve clearance is always adjusted at thepush rod. DO NOT DISTURB the exhaust valve bridge of the exhaust valves may be adjusted duringone full revolution of performing valve clearance adjustment on a cold engine the governor stop lever in the NO- FUEL the crankshaft until the injector follower is fullydepressed on the cylinder to be 1-7 CAUTION: When using a wrench on the crankshaft bolt at thefront of the engine, do not turn the crankshaft in a left-handdirection of rotation; this will loosen the the push rod lock " feeler gage,tool J9708, between thevalve stem and the rocker arm (See Figure I).

7 Adjustthe push rod to obtain a srr ooth "pull" on the feeler the feeler the push rod with a 5/16"wrench and tighten the lock nut with a 1/2" the this time, if the adjustment iscorrect, " feeler gage will pass freely between thevalve stem and the rocker arm, but the . 013" feeler gagewill not pass and adjust the remaining valves in the same manner,as outlined ,.. " '5*4*--,FEELERGAGEFig. 1 - Adjusting valve 'k/.7111,PTAMWhen perfuviningvveiectuanee adjustment on a but engine, rememberthat maintaining the normal engine operating temperature is particularlyimportant when making the firat valve clearance the engineis allowed to cool off before set ting any of the valves, the clearance whenrunning at full load may become the engine at normal operating temperature (160 to 185 F), recheckthe exhaust valve clearance with the feeler this time, if thevalve clearance is correct, " feeler gage will pass freely betweenthe valve stern and the rocRer arm, but " gage will not pass the push rod, if Exhaust Valve Adjustment o.

8 Engines with Four ValveCylinder Heads (Cold Engine)--The above steps used to adjust valveclearance on engines with two valve cylinder heads are exactly thesameas those used with engines having four valve cylinder heads except insteps 4, and 6, as step 4-- place a . 017" feeler gage, tool J9708, between the end of thevalve stem and the valve bridge adjustment screw (spring-loaded bridgeonly) or between '.he valve bridge and the valve rockerarm pallet(unloaded bridge only).In step 6--recheck the this time, if the adjustment iscorrect, " feeler gage, J9708, will pass freely between the valvestem and the adjustment screw (spring 'loaded bridge) or between the valvebridge and the rocker arm pallet (unloaded bridge), but " feelergage will not pass the engine at normal engine operating temperature (160-185 F. ),recheck the exhaust valve clearance with the feeler this time,N5 PTAM 1-7if the valve clearance is correct, " feeler gage must pass freelybetween the valve stem and the valve bridge adjusting screw (spring-loadedbridge) or between the valve bridge and the rockerarm pallet (unloadedbridge), but " gage must not pass the push rodif good tip to remember is:after checking the adjustments, mark therocker arm with chalk as you complete each one, to keep track of what hasbeen STEP No.

9 2-- TIMING THE INJECTORS -- NOTE: Unlessspecified, the same procedure (below) is used on the inline series as onthe Vee the rocker arms for checking injector timing. Crank the engineuntil the rod clevis ends of the valve rocker armsare up, fully de-pressing the exhaust the engine may be done by depressing the remote starter sure the stop lever is in the stop position before cranking the you use a wrench on the crankshaft bolt or crankshaft nut, besurenot to turn the engine in a left-hand direction of rotation, as the bolts willbe the injectors can be tuned during one full revolution of the Table 1 to identify the proper timing gage necessary to turn theinjector in your 1-7 InjectorTiming GageDimensionITiming GageTool "J "J "J "J "J 1853S551,460"J ". "J "J ". "J "J "J ". "J "J "J 1853N651,460"J "J "J "J 'J "J "J "J "J ".

10 "J "J ".11853 Table 1 - Timing gage chart for injectorsTime each fuel injector as outlined the governor speed control lever in the NO-FUEL the crankshaft until the exhaust valves are fully depressedon the particular cylinder to the small end of the injector timing gage in the hole pro-vided in the top of the injector body with the flat of the gagetowardthe injector follower, see Figure the push rod lock the push rod and adjust the injector rocker armuntil theextended part of the gage will just pass overthe top of the in-jector the push rod and tighten the lock the adjustmentand, if necessary, readjust the push the remaining injectors in the same manner asoutlined inItems 1 through ( - Inserting the injectortiming STEP No. 3 LIMITING SPEED MECHANICALGOVERNORAND INJECTOR RACK CONTROLADJUSTMENT - (INLINE)After completing exhaust valveadjustment and injector timing,there arefour governor adiustments to be inline engines areequipped with either asingle weight, ordoubleweight limiting speed Vee engine hasonly the , on the Vee engines,there are two typesof double weight limitingspeed in adjustmentsfor both types will bepointedout in the following THE GOVERNOR GAP ONLINE SINGLE WEIGHT TYPE)