Topic: Timing mark???
in Forum: C3 Engines
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Hartland, WI - USA
Joined: 4/5/2008
Posts: 5
Vette(s): I have my FIRST VETTE it a 1974. L48(Engine Suffix CLC), ORIGINAL COLOR(Paint Code 74L), SADDLE LEATHER (Trim Code 416), AUTO, AC, PS, PB, PW, T/T Steering Wheel, GLASS T-Tops, MAP LIGHT all matching #'s Over all Fair shape always a work in progress!!!
When I use a timing light on #1 wire, the timing mark can't be see on harmonic balancer when the engine is running! Is there a possibility that the key way is missing or broke off? Engine is running good right now!!! Any ideas??? THANKS
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It's possible the key is gone ,but I doubt it,more than likely your harmonic balancer has started to come apart.basically the balancer is 2 pieces,an inner ring and an outer ring ,with rubber in between them.the rubber starts to decompose and the outer ring moves,ergo the timing mark moves.it's probably time for a new harmonic balancer,B-4 it totally comes apart,an raises all kinds of h e l l 
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Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
or you could be testing it wrong and it just isnt in range.
cthulhu 2008-04-27 17:42:59
ive seen way too many people do this.
did you pull and plug the vac advance.
is the car idling at the right rpm (800 auto, 1000 stick)
im assuming you have an older style analog light as well. I have a calibrated digtal light with advance and tach, etc. and i have an "old school" analog light that isnt even in the ballpark. I've opened it and it doesnt have any calibration pots. it is junk. I use it to illustrate how unreliable low end analog lights are.
I have another.. an analog offset light that I had to calibrate myself as the timing at 0 offset was correct but the offset dial was basically about 50% too high.
so when you dialed it to 10 advnace it was really 15
all of this to stay that i prefer to set initial timing by vaccum and have detaield the procedure in mind numbing detail here quite a few times.
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Vette(s): 1980 with a Banks Twin Turbo
1969 Convert Big Block
1996 Grand Sport Convert
I'd have a Real Good Look at the Balancer and find the Timing Mark on it and Paint or Mark it White as this shows up Real Good with a Timing Light. If the Rubber on the Balancer looks bad You might just replace it. Then I'd Remove the Distributor Cap and Bump the Engine over till the Rotor is at the #1 Spark Plug. At this Point You should be able to see the Mark somewhat near Top Dead Center.
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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Ben's Timing tips 1
Ben's Timing tips 2
You either have your light on the wrong plug wire, or the outer ring of the balancer has slipped.
You can use Richard's(Gale Banks 80) method to get the #1 plug up on it's compression stroke, and see if the balancer mark is off. If the outer ring has slipped, the balancer should be replaced. It can cause major damage to the car if it comes completely part while driving.
Ben's Timing tips 2
You either have your light on the wrong plug wire, or the outer ring of the balancer has slipped.
You can use Richard's(Gale Banks 80) method to get the #1 plug up on it's compression stroke, and see if the balancer mark is off. If the outer ring has slipped, the balancer should be replaced. It can cause major damage to the car if it comes completely part while driving.
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Former Member
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Hartland, WI - USA
Joined: 4/5/2008
Posts: 5
Vette(s): I have my FIRST VETTE it a 1974. L48(Engine Suffix CLC), ORIGINAL COLOR(Paint Code 74L), SADDLE LEATHER (Trim Code 416), AUTO, AC, PS, PB, PW, T/T Steering Wheel, GLASS T-Tops, MAP LIGHT all matching #'s Over all Fair shape always a work in progress!!!
When I bring it to the compression stroke the mark is way off still! must be the balancer slipped!! Looks like replacemen time!!!LOL after that I plan I trying the Vac method to set the timing. We'll see what the differences is then... then everyone!!
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Vette(s): 69 Conv #'s match 427, TKO-600/.64, 3.36HD-Posi, HT, T/T, PS, PB, PW, SP, Leather, Comp XE264HR & Roller Rockers & Lifters, Air-Gap RPM intake, Holley St Av 770 VS, MSD 6AL+Dist+Blaster SS, K&N, Jet-Hot Hooker Side-Pipes, Steeroids, Al Rad, Spal Fans
[QUOTE=Adams' Apple]Ben's Timing tips 1
Ben's Timing tips 2
You either have your light on the wrong plug wire, or the outer ring of the balancer has slipped.
You can use Richard's(Gale Banks 80) method to get the #1 plug up on it's compression stroke, and see if the balancer mark is off. If the outer ring has slipped, the balancer should be replaced. It can cause major damage to the car if it comes completely part while driving. [/QUOTE]
Ben's Timing tips 2
You either have your light on the wrong plug wire, or the outer ring of the balancer has slipped.
You can use Richard's(Gale Banks 80) method to get the #1 plug up on it's compression stroke, and see if the balancer mark is off. If the outer ring has slipped, the balancer should be replaced. It can cause major damage to the car if it comes completely part while driving.
[/QUOTE]
i had balancer come off on a 72 caprice while doing about 80....
needless to say the shroud was gone.. radiator too....
not pretty
Lifetime MemberJoined: 9/8/2005
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Vette(s): 1980 with a Banks Twin Turbo
1969 Convert Big Block
1996 Grand Sport Convert
The other night on the Speed Channel Pinks a Balancer came off a Mustang ( no Surprise) and He went ahead and Raced it one more Pass. The # 6 Rod blew a Hole in the Block but Yes it was a Ford. The good news is that 90% of Fords are stiill on the Road today. The other 10% made it home. OK OK my Method of Finding #1 was very Crude and not very Accurate but should give You an Idea of how far off the ballancer is. A more accurate way would be to remove the #1 Spark Plug and install a Piston Stop and Turn the Engine over by Hand untill the Piston Runs into it. Mark the Balancer at the Timing Mark on Cam Chain Cover and then Turn the Engine the opposite Direction untill it stops again and Mark it again. Top Dead Center will be 1/2 way between the Marks. You can make a Stop out of a Wood Dowel. Of Coarse if You have allready determined that the Balancer is Bad this is all a waist of Time. If Your Car is a Rare one You may Consider Rebuilding the Original. I have never done this but Some of the Restores should know who dose.
I have a white grease pencil (an old tire lettering crayon). I mark the groove in the balancer and the timing mark on the tab. Wipe off the excess, fire it up, and turn on the timing light. Works like a charm.
in Forum: C3 Engines
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