But check to see where # 1 is first....
Timing Question
Thread Starter
Intermediate
Joined: Aug 2011
Posts: 33
Likes: 0
Timing Question
I bought this 78 about 2 months ago, it has been running fine. I thought i would check it's timing. Engine was warm, plugged the vacuum advance, hooked up the inductive timing light. Started the engine, pointed the light at the timing mark and can't find timing mark on the balancer. Shut down the engine, bumped engine until I verified that there was a timing mark on the harmonic balancer. loosened the distributor, started the engine and check it again, moved the distributor about an 1/8 th of a turn and can't find the timing mark in the timing light. What am I missing? What should I be checking
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Odds are that the distributor has been re-clocked by #1 cylinder being shifted one plug wire off of the normal location on the distributor cap. Don't assume that the #1 plug wire is located where the "book" tells you. Your best bet is to move the distributor back to where it was, then check for a timing mark on the plug wires on either side of where you think #1 wire should be located.
Once you figure out which wire REALLY goes to the #1 cylinder, your problems will be resolved.
Once you figure out which wire REALLY goes to the #1 cylinder, your problems will be resolved.
Melting Slicks
Joined: Aug 2010
Posts: 2,487
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From: Palm Beach Florida
St. Jude Donor '12
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Drifting
Joined: Dec 2004
Posts: 1,714
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From: Austin Texas
Thread Starter
Intermediate
Joined: Aug 2011
Posts: 33
Likes: 0
Found timing mark for #1 is currently at 12:00 position, when I try and adjust the distributor to get to 4 BTDC it becomes very rough. Checked to see if any of the other cylinders would give me the timing mark and none would. So what am I facing? A slipped balancer or a distributor in the wrong spot?
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
Definitely a slipped balancer, needs replaced as stated earlier. Hit up the local parts store for a new one and many of the stores will rent the puller for a deposit that is refunded when the tool is returned.
Le Mans Master
Joined: Dec 2007
Posts: 6,422
Likes: 591
From: McHenry Illinois
Pull out the #1 spark plug and turn the engine till the timing mark lines up. Put a screwdriver in the hole to touch the top of the piston, then rotate the engine in the opposite direction, so the timing mark goes up, probably the piston will go up farther indicated by the screwdriver moving. If the balancer is good the timing mark will line up at 0 when the #1 piston is at the top. Sounds like yours is far enough off that this simple method will tell the story. Also if you remove the lower belt pulleys, there will be a key way inside the bore of the balancer hub which should be either lined up with the timing mark on the outer ring or a very few degrees off depending on the year of the engine.
Drifting
Joined: Mar 2011
Posts: 1,886
Likes: 9
Don't even think about using a hammer!