1974 FORD CAPRI spark plugs

Chapter 1 Engine 49
----------------~--~----------------= anuill transmiSsIOn models, remove foul clops bolt~ n automatic 1.,J;lsmission .models. drilm the torque conve!ler ,\Ild 18 Ihe drivep l . odelS make s"re Ih,lt the torqlle converter ,em,,!!)s lilly 1f1 1he $lOI1 m transmission . 20 When the engine hilS been SCpM,lICd from 11l(l 11.,11$1111551011, 1,lllh!.! . ,lowly chccklll9 j,equently to see (hMllle CflUllle does not loul " ng,ne . ~nv part of the bo?ywork. 21 W hen the engUle 's cle,lr of the iJody . lower it to the ~lfOun(i. Of
Ir~nsler it to a WOrk lJench
4 $ Engine disill1lotling -generill
Refer \0 Sec t,on 7
46 Engine illlcillilrics -removi\1
..
1,',lh the engine sep,l rated from th" t r;IIl~:nHS~r()" remove Ihe ~.tcrnally mounted componelliS ;l~ lulluw~
C;J//)Ulello, i.lnd fllcl {lump (C"'1!,lt" 3) IlIlel ,wll exhiwsl tII,wi/a/ris (Chaf!/t't 3) Sp,>r/( plugs and drS/fllmlor (Chaplet 4) AllCllwlor (Chaplet /2) F.w ,7I!d policy (CII,71I1C' 2) W.JICf pump ,wd Ihcffllos/.1I (Clmp/t't 2) C, ,1IIkc,lSC vcn/iliilion lubc 011 {,f/CI (Scc/ion 40) Ol/Icvl!! r/rpsllc/o; and {,/lCf C,?!, [II!1int' 1II01tn/ill.ll h,.1r:kvls Ciulell (Ch,7/I/l'l 5) Powl'r S/Cl'l/IIN 1'(11111' (Ch;lll/Vf 10J
<11 Cylind(Jr heads relllowti with engine in car
I
Q,scunnecllhe IJiltlery le,lds ") ~cmove the splilsh slucld. by renuJVIII , R ernove the servo V,lCUlUl1 hose I ~ DI~conrlccl Ihe rilll,.llul hose from Ihe ilulomallC choke D,s·
,onneCI the vac\JUnl h"e I • D,sconnect" I I I 10 0 le ea( co I I~con"ecllhe HT ICilds Irom the spark plugs and IrOlillhe Ign'llon I ,1od remove Jlw L T I I I I .
MId I I If . CiI( 10 lie dlSl1i Julor Reillove aile h Xlng bolt 11 0
' I
a Ihe dlst"I>[1I0r ilSsemlily.
'Sconllect Ihe all II 51 halts' , ' ernillOr Cil) es. ilcken the ailelllntor 1110ul1l11lg un( Pusil rod . C,II1)e "Oled. 11 IS very Imporl "IOC>! "
Fi~,. 1 .10 Turn the rocker (HillS to olle side 10 relllove the pushrods (Sec 47)
15 n,,,,,ove Iwelve lIolts ilnd delilch Ihe exh,lusl I1\,lrlllolds frOI" Ihe cylrrlrtr:f he,lds. 16 Sinckell the cyhmter hend boilS progressively in the revtnSe order to Ih"l shown ill FIll 1.19. IlcrllOVC Ihe bolts nlld hit olt Ihe cylindOf head.
It lile (.Iilsket has stuck and the cylrnder heJd cannot lJe lifted off. wp the cylinder heild wllh n hide·f.1cert. or plnstic·headed hJmmer. 00 nOI try to pri se IlIelil off wllh a screwdrivOf Of rtilillage WIll result.
4 8
Cylinder he,l(ls -rernovfli wilh engine O\lt o f car
Follow Ihe sequence (.I,,·elllll SectIon '17. 51;lItll1g.l1 PillillJl1lph 10. dl$lcoa,d,n!1 leil.!lellCeS to pa'is willch hJve alreildy bcen rcmuved
49 Villve$ _. removal
Rt:rllove the d('POSIlS /'0111 tire corllb\lsl,on chambers ~nd vnlve
h eads by ScrilPIl1!l and W" ~ b'\Ishlll(.l Tilke CJre nOI 10 scratCh the cyllnde, he~d gaskel lilces 2 Lay the CylOl(ier hemt on ,IS sllll) .llld h t the lo,~ed cnd of .1 VJlve spllng compressor ove, the ~plln9 rctiluler ""d ti le head uf the complessor screw in Ihe cenl'e of Ihe v"lve head 3 Compress Ihe sprrng abolll " qUJller 01 an Ulc h 10 Iree Ihl} split colle l hom the top 0 1 the v,llve stelll. If Ihe sPltng ,eliHner "nd collel Slicks. do not screw the co",p,essor down lurlhc< . bec"use IIIIs lII.ly dJr11J\je the valve Slem. bUI lJp the sprong reliluler sha,ply wllh a Ioghl
hammer. 'I When the Iwo halves of Ihe collet h')ve been '(:nloved. onscrew the spllng compressor umrl Ihe spring IS no longe, compressed nnd
remove Ihe compreSSOr . 5 f1Olllove the spltng retnlner. the spflng and the oil seal from Ihe villve Slem. Ihen wrlhdrflw Ihe villve from I he cylinder head. 6 D iscard the valve Slem all senls and plflce Ihe Olher componenls to\jellrCt. identilying them so Ihal they arc refItted III the correC I plnce
III Ihe cylinder head. 7 Remove Ihe sp,11k plugs from Ihe cyhnder hend. II nOI alrendy
removed.
50 Rocker arms -removal
1 Remove the SIIfI nul from Ihe foch" .1'111 Illoullt,n\) stud 2 Lift off the rocker re moved.
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Chapter 4 Ignition system
Contents
"'ondcnsc! (30 Iotre cnUIIlC) teslI llU . removal and rc h1!ln g .... 5 '"tact b.ellkc . POIllIS (3 .0 litre CIlUIIlC) ,lI 11us1mC lll 3 ConlilC ! brCi.ke< POintS (30 lIue cnumc) -Hlllloval fllIIl rclr ninH . " f" '~lnb\llo, (1111 CIl\ Ji llCS) lema",,1 .lIlt! .cll1l1n\) (j nhlllOr (28 lilre Cilomo) -overhalll.. 8 D,stributor (30 h\le cnuinc) overhaul . 7 Faull diagnos is -iUm\loll system. 12
S rICcificin ion s
System ty pe
3.0 lit.e engine 2.8 litre engine
Convent ional ignition
Distributor
ROIDlion Condense, cnp Iqnition timing
c 1 !H6 model yC Jil
I',im Spark plugs
Type Elect. ode U .
8reaker/ess igllilion
Distributor
Rotation .. HT lead rCSlstn llCe .
Firing order
Ignition timing
Coil
Primary rcs,sWnce
Secondary resis lan ce ............... .
Spark plugs
Type Electrode {jap .
,1/ systems
Torque w rench settings SpD,k p lugs (3.0 litl(l CIl!JUlC) SPD,k plug s (2 8 hl,e engine)
Geller,11 dCSCfll>, ioll 19r1lllon tnnphlicr Inodule (2 8 hire engine) -. emov,l l and 'Ch1tmO ... ......... .............. . IUrlltlon timinlJ -ndJuslmcnl . flOulUl!) Ill;untenancc . Spark plugs -rem Oval, servicing an d .cl'!lu \g ,
ConvcmiOllill. with cantilCl tu cilke. Br eake rlcss. clCCltOnic
Clockwbe 0 2110025 mid
0 .61 mm (002510) 36" t o <10 · 30000 ohm mOlX"U,uU 1 <1 2 5 3 6
10"' B1 DC 11\· BTDC
0!l5 10 1.60 ohm 50001 0 !l300 o h m
M ot
o,,,,,lt AGR 22 o. Ch;lIllp lon RN 9Y C 060 IlHIl (0024 in)
Cl ockw,se 30000 ohm Il1 12 *
BTOC
0 .
75100.85 o hm 5000 to 6000 ohm
Moto"ra" Super AGR O .GO mill (0024 in)
N rn 30 to GO 25 to 38
22C 0' ChJlllplon RN 7YC
Ibl It 22 to 30 1 8 to 28
10
9
2 11
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Q
Chapte r 4 Ignition system
®
0 -
-@ @
Fig. 4 .1 Diagwll1 of the hre(lkerlcs5 ignition syslem on the 2 .a litre engine (Sec 1 )
A higgcf ",,(I stiltor ,1(111$ 8 Am/Jlt/icf modufe C Iylll/ion SWJ/i:lr o BMI£'fY E 'm:lmJIIl"/l:f F COIl G D is/nUll/a , c.-,/! H Ho/or .11111 J 5p,1fK, IJ/ug K 'fi''l)CI co,1
Gcneral de:;criptio n
To ;l(; h.cvc OP\I"'U'" pCl lo.mancc hom an CIl(lUlC ;\Old In mCCI ~1""\JCUt e.h,1u~t C""5s"m r .. ' - '),uk nece ss1Hv to start thc: Illlxlu1I1I""!1 ;md the In~t;"l\ ill wh'ch ,union occurs IS Y;lrI"d auwnJ.1tlC;lllv as ""\line Opet(lt'U g cOl1llot'I)I1 $ d';1r1ge The ''In,tlon systc)t1I COIIS '5 15 01 a PWll;IIV (low tc n slon) CUClnt ill"t J ondarv (1I1g11 tens,on) Cirelnl. Wlwl I he '\lnI\IOIl IS SWltchlid on. CUlrellt IS fe d 10 Ihe coil p r;111;uv wirl(hllUS nnd i1 IIHl\l11Ctic f,p.ld IS cst~lbhshC(1 At Ihe r equired 1)0"11 o r 101l1\10n. the pri"':Irv CItCl/lt IS Ifl tcrruptClluV the conlnct hfenker POUlIS OllCflmg (3 .0 hire e"gI01(I) or the \l'g\le. tJrfllpasslt'g the s tator ;11111 (2 8lrt,e enUn .e) The milunCIiC
f 'eld collilpscs :Ind il 5tlCOndntV hi~h YOIIIl~~ In 'nduced i n the se~ond,1rv win(lin\!s. This HT volt:lUc IS te d via th e d'SH ,IJUtor rOIOI :Iun
1 0 the lelevllllt spnrk plu~. Alter dcllvenng the spar k the pmnnrv cirC Uli
I S re-energised lind the cvcle .s rep-Cillcd. The igni tion t iminu '5 Controlled centro lugllllV JnO UV II vacuum IHl II t o compensme lor englflC speed ,1no 10lld On Ihe 3.0 litre enginc the i~l1;lion s y Stelll II1corporales a b,1ita $1
resistor wire which effcctively UOOSIS th e HT volw~e durlllg SHul,ng.
2 Routine m aintenance
At Ihe in tervals speCIfied in tl w Rouline Ma;ntenance section in the fran I of the nl;Jnua l cJrrV out the foll owmg proc edures .
Clean and adjust Ihe spark plugs. or renew Ihem 1 Refer to Sec tion 11.
Clean ofld chec k fhe distribulor cop. rolor. NT leads illlr/
t. Re lease the twO chI'S securmg Ihe (h Slllbu101 cap 10 Ihe d'5111l1utor uodV and I, ft away t he ca l) . ereJn Ihl;l C:lP inside and oul wilh a dtv
---we F
Fig. 4 .2 (J"II(ls t resistor wire locilted on tho left·h'Hld side of the ongino compartment -urrowed (Sec 1)
clO lh . Closely inspec t the ",side of thc cap and the si. segments. It there are any siUns of Cr<1Ckulg 01 ,f the segmentS are bumcd o. scorl;ld e~cessivelv the Cal) will h ave to be renewed.
3 Also Check Ihe cenlrc segment (3.0 htr a en\]ine) or carbon brush (2.8 IIlre engine) f or wailr. 4 Remove the rOIOI arm i1nd check 1110 ' cra ck ing and burning of the melal scgmem (pholo). On the 2.8 h ire en gin e check tM Sp S W'th Ihe . o to r aIR. removed. lub.icate the felt pad in the Centr e of the distfluutor sh ah wilh twO drops o f enyine oil. 6 Rel;lthe rOtor arm and dt$Uluutor cap (photo).
d
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Monsurin g plug gnp . gaugo ;;:;;;-;;;"",,',,"," ignition sysICm spccilicalions) should have a sliUht 'drag' when slid between the olocuuch~s. Adjust {[liP if necessary
N orm al. r, dcpo~il~.liUlolly coaled corc nose. increasing by around 0.00 1 in (0.025 mm) pc, 1000 miles (1600 km). Plugs ideally suited to en\j ine. "nd engine in good
condition
Oil fouting. Wet. oily dr~pOl;its. cal,se eventually misfirc. Fllult : wmn bores/ilision 'ingSOf valve guidcs: sometimes OCC"'!! (temj.lO'Hrilyl d .. ring lunning-in
poriOd. Plug~ C()I1 IJ() H! u~ecl "ftc. thorouUh cleaning
-," ..
. \\'
in Electrode demoge. ;;;;,:;;;;;;;:;;;~;~;';::;;i ;;,,, ",,;; h;,
bumed, glazed appearance. Fa ult: pre')gnohon Check: as 101 'Overheating' bllt may be more sovero. Discard plugs ar1d rornedy fault belorc piston or v31vc d~",age occurs
.'
.. ", . ~,'''':c." ~~:~~~~~~::i, Adjusting plug gap. Tlu, plug gap is, 03rth electrode inwards, or oulwards, as I correct clearance is uillaim!d. NOlO II,,! use 01 tho COlfcct tool
spark ami I I' Chock: cMhulOllor , • sellings, 1I0al level ,lIld iot siles; c hoke (lJlOla lion .mel cltlanli n()ss 01 ai, fillel. Plugs can bo rc­usod :"1 Overhoating EI()cuud'ls h,lVO \Jlilwd ~ppcaf3nce, CO'O noso vely while lew dello~iIS. f;I!I't Ilh,O uvelheatinu. Chec k: plug
vlJlue, iunitiun limill H. I"clu t;lillle I1Itillu (tOO lowl mixture lWQ w('ak). DisC , ,.
i Split cor o noso (mny npllollI i 8 crBck). Damage is
sel f.evide nt, bUI cruc ks will only showalter cloaning. Faul t: pre­ignition 01 wrOIl!) !)ap settin!) technique. Check : ignition liming,
cooling SYStCIl1. 1",,1 O C t;"" .. r alin!) (too low) and fuel mixlure lton woak) . Discilld "Iu!)s. ",Clllv laul t immediately
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Chapter 4 Ignition sys te m 95
)
) .. . '.
. 2 1!11"I'On ampllf,er mod"l~ .1m1 mull< .pluu eOllllecto,s
2 With til() l~pll!lOn sw'tehud off rhsconner.1 thO two llIulu·plu!) comW(:I 11 Spark 1)lugs -re m oval, servicing and retitling
l' Rem ove the ilir clea ner or inl et duCling ilS rC{luuC tl. 2 Identify Ih c HT leads for posi lion \hen c11Se 0I1I1CCI them from thc sp.,.k I)I!I!J$ hy plllhn!) on the IC'fl,i",11 ends. not Ihc tIIilin leilds (photo) 3 US'''!! a sp;"k pluy Sl)ilnnrlr. unscrew tllf! pluUs 1'0111 the cyhnder
h
Ci'ld s (ph"lo~1 4 H Ih'l IIl',,,laIOl no~ of Ilw sp",k pl"H IS dean i'lnd wh,te. wl1h 110 (ICPO$115 tlw;.~ ".dlCo1l1ve of a w,~;,k n"~IUH1. 0' 100 h o t .1 plug (,1 hot plug II;'n~h:ts 1",.11 aWily fWIl' t he I)h.~:I.odc slowly il cold I lhl!1 triHl sle.s ,I ;rw.lY "",dly) <; lhl! IIltl!JS f'l1l:d ilS stimrJi"d a'c ilS hSICd IIllhoJ S pccifleallol1s!lt Ilic ha. d black look",U depos.ls. th..,,, Ih .s .s ,mheilhve Ihilt Ihe m'~I\I.e IS o "eh Should Ihe plllg he h l"ek amI Oily. Ihen II IS lik ely thaI the .I U ine IS fairly W Olfl. (IS well il~ Ihe mixilne benlU 100 Itch 6 If th c lllSuliltor nose '5 cove.ed wnh I I\Jll t Ian 10 glcY ls h blown (ICI>oSIIS. Ihen Ihe mlxllue's CO"I..'CI ,lnd II '5 h kely Ihallhe eng"'e IS ill good condurOll 7 "the.c ilfC illly Iraces of lo"g b.ow n tnpC""1J stilU'S onlhe OUlslde 0 1 Iho wh'le pOl lion ollhe plug. the n th O pl\l\: 1 W ill h,1V(l1O be renewed.
as Ihis shows Ihiltlhere .s il filulty Jom l helween Ihe plug ilnd body and Ihe insulilIO '. and comp. ess.on .s beltlU ilflowed co IC 3
4 \)6
Fig. 4 .6 HT I Cild l)osilion5 o n the 3.0 l i tro C "~Jine (Soc 11)
AllOW III'''(;,lICS ,,,,,,1 ul "'''UtllC
Fig. 4 .7 HT lead posit io ns 011 Iho 2.8 lilro engino (Sec 11)
AllOW imilc,lles I'UII ! 01 ell!}"''''
8 Plugs should be clCilned by.1 So,,,(1 hlilsung n'achme w hich w.lIl.ce thcll' from cil.bon mo.e Iho f
enewcd.
~. . -,,' ;-------
..... -.,.""I'~ -, .. C"
-C~i < , ','" , ,., :.."
.---.
. ~~ ' . ." , _ t~ .
,
I • I 2 DlSCOllllCC I thO lIT leild . 11.3A ... unsc.ew the spa.k plug I I 38 and remove 11
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,6 Chapter 4 Ignition system
9 The spark plug gaf} is 01 conside rable impor1~e. as. if it is too lilrge or too small. the size of the spark ilnd its efficiency will be seriously impilired. The spilrk plug should be set to the ligure given in thl} Specifications ill the beginning of this Chapter; IOTa sel it, measure the gilp with a/cere, gauge. and then bend open. or close. the outer plug electrode untillhe correct gap is achieved. The centre electrode should never be benl as this may crack the insulation ilnd cause plug fAilure if nothing worse. 11 Relit the plugs, and re/ilthe leads from the distr ibu tor in the correct I"ing order. which is given in the Specifications. Screw the plugs in by hilnd initiilily then tighten them to the specified torque using the plug spilnnel.
12 Fault diagnosis -ignition system
By lar (he nlo1jori (y 01 brCJkdown and running troubles ilre caused by InUits In the igrlOlron system er(her in (he low (enSlon or high tens ion circuns There LJratlon or fuel Injec tion Setlln(Js, ilre normally tllle to faults in the d,strrllulOr Or 10 Incorrect I(Jrlltion tlllllrl!J .
Engine fails 10 staft 1 If the engine falls to StM( and t he cal was IIJnning norll1t1l1y when.t wns IJst used, first check ther e is fuel in the petrol wnk. If (he engille tums ovel normally on (he starter 1I10tor and the bilHery is evidently well chmged. then the lault mny be in either the high or low tension circuits. Firs( check Ihe HT circuit. Note: If lire hal/cry is known 10 hI! {(Illy ch,}lged, Ihe ignilion liglll cOllies on, ,1I)d Ihe s/arler 1II010r {,lils /() tum IIIe ongine check the tightness o f the le'lds on the biltlely terillinilis ,1I)d <1Iso (lte seCUIIHWSS oflhe e,l,th leold (0 irs cOllllec/ion 10 tire body It is qui(e common for tlie le,1(ls /0 Ii,}ve wOlked loose. l.'vc'1I If Ihey look ,1n(/ lecl seclI,e. /I one 01 the boll/my ((:{minM {Josts [11.'1.1' vC'IV liot wi".." (Iyiny (0 wOlk Ihe s/mler 1II0tOl (his is ;/ sUie IIId'C,7/IUI/ 0/ ;/ I;wlty COllllel;('On 1(1 1h.11Ie"lIillal. 2 One of tile commonest rOilsons lor bad stmtln!J IS wet or d;UllP sp,uk plug lead~ and dlstribu(or. Hemove (he distllblltor cap. H "JOdenSil(Ion is v iSIble IIlte!llillly dry the CJp With il rag and also wIpe ;lCf the leads nelu the cap_ 3 If (he enUiue sull fmls 1 0 St.l.t. check that cunent IS reachlllg (he JUS, by dlscounectln!1 ench plug le,l<1 in turn ilt the sp1Hk plllU end, .. ,ld holdlllg Ihe end olthe callie about 5 mm (0.2 Ill) aWilY from the cylillder block. Spin the enu'ne all the sta rter motor. 1 Spa,klllg between the end of the cable ilnd Ihe block should he fa"ly strong With J strong leuulm blue spark_ (Hold (he lead WI(h wbber to ilvold elec(IIc shocks) If Clluelll is reilching (he plugs. then rel110Ve them and clean and reg,lp them. Tho engine should now SWrt 5 If there is no spilrk ilt the plug leilds. wke of! the HT lead from the cenlre of the d'sltibutor C 6 If Ihere me no spmks Irom the end of the lend 110m the coil check the connections atlhe coil end of the lead. If il is in order 5(31 1 checking (he low tension circuit. 7 Use iI 12V voltmeler or a 12V bulb ilnd two leng(hs of w ire. On conventional distributors switch on the ignilion i1nd ensure tha t the points arc open. On breakerless dlstlibulOlS ensure thilt Ihe segments on the rOlor are nOt adJilcenl to (he triggel coil. Make a tes t between the low tension wire to the COil ( + ) terminal nnd eilrth. A leading of 7 (0 8 'lollS should be obtained. N o reJding indiCiites a break in the supply from the ignition swilCh or il f,1UIl in the ballast resiswnce wire. A correct rending indicn(es a faulty cojl or condensel, or n blok en lend between the coil ilnd the distrIbutor. On breokedess ignition systems the (rigger coil and ilmplificr module are suspect . H~ve (hem checked by a Ford dealer. . 8 Take the condenser wire off the points assembly Jnd with the points open test between the moving point ilnd eMth. If there is now a leildrng then the tault is in (he condenser. Fit a new one as dcsclibed in this Chapter, Section 5 9 W,th no reilding from the moving point to eilrth, wke ,1 reildrng between eil/th ,1nd the ell or negiltive ( - ) teminal ot (he COIl. A rendm(J here shows a broken wire which will need to be renewed hetween (he COil ilnd dis(rihutor. No retlding confirms thil1the coil hilS failed ilnd must be renewed, afler which the eno"te wdl run once more Rcmtmher (0 rel,t tho condenser wire 10 the pomt$ ilssemhly.
Engine misfires 10 If the enOlnr. mlsfues re!Julariy. run It ilt a f~st irllrng speed. Pull off eilch 01 the plu(! C,lpS III hUll nnd hsten t o (he note 01 the engrne. Hold the phl(J cnp In il dry cloth or with a rubber g love other Pollt of the dlstllhu(or. These lilles J,e p,lths which now conduct electllcit y Jcross the CJp lhus lewng it run to e,,'th. Tile only answer IS a new distllbutor CilP_ 16 APilit frorn the Ignition tll1l1ng being Incorrect. other Ciluses of rlllsl,,,ng hilve already been denl( w l(h under Ihe section dealrng with the f,lriUre of Ihe enuine to star I. To reCi!p - these 0110 Ih,lt:
(,J) The cOllm.lV be {,lufly giving ,111 iniNmil/elll mislile (b) Thele limy he ,1 (/iJmiJged wile or loose cOrlflee/ioll in till! low (eflsion circuil (c) The condensel /II,lY I;e shOll circuiling (i{ filled) (d) There nwy be a meehanic,lllolUI! IiI Ihe dis/flbll/or (bfOken dliving spindle or eOlllac/bleaker spring. if filled)
17 If the ignition (iming is too far reto1lded, it should be noted thallhe engine will tend to overheat. and there will he a quite no(iceable drop in powel. If the engine is overheating and Ihe power is down, and Ihe ,oni(ion tim in!) is correct. then Ihe carburenor or fuel injection should be checked, i1S ,I is likely that this is where the Iilult lies.
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