Distributor question
Thread Starter
Instructor
Joined: Mar 2013
Posts: 180
Likes: 21
From: Chesterfield Mo
Distributor question
Engine is 75 L82 with HEI. With the timing mark on the balancer set to 0 the rotor on the distributor points straight ahead not at the number one terminal. See the pictures. The engine starts and runs well as set. Is the distributor off a tooth or is this normal? I know that if the distributor is a tooth off the timing can still be set to spec if the distributor vacuum can allows the distributor to turn far enough. Am I imagining a problem where none exists?
Cruising
Joined: Apr 2008
Posts: 10
Likes: 0
From: Knoxville Maryland
Make sure cyl 1 is at TDC and check again, if rotor is not alingned correctly, pull distributor and reset in proper position, Start the beast and set the timing. Be sure to mark the distributor housing where the number 1 plug wire lines up first.
Burning Brakes
Joined: Oct 2008
Posts: 1,037
Likes: 14
From: Mobile Alabama
Don't pull anything out just yet. Get a timing light and check the timing properly. The distributor does not know, or care, where number 1 is plugged into the cap. You could move the wires to wherever, and as long as they are in correct order, and the rotor is clocked to match -you are good.
Burning Brakes
Joined: Oct 2008
Posts: 1,037
Likes: 14
From: Mobile Alabama
You said it is running well as-is, so if the light shows the timing way off, you might have to start from scratch. I have seen balancer rings twist and show wrong. Someone could have changed out the pointer and it doesn't match up. But don't just tear into it before you have a good idea. It is running.
Thread Starter
Instructor
Joined: Mar 2013
Posts: 180
Likes: 21
From: Chesterfield Mo
The engine is set at TDC on the balancer, see photo. It seems that the rotor should point to the number one post on the distributor. The rotor points straight ahead. You can see the number one post on the cap is offset to the side. On my older 62 distributor the rotor points to the number one post at TDC. This is a new old car for me so I'm trying to correct things that are incorrect. I guess Im wanting someone who knows to say, Yes it is a tooth off or it is OK.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
At TDC (0 degrees), you are way past the firing point, and the rotor will not be pointing to #1. If the engine times fine, there is no issue.
The photo in your first post shows the distributor perfectly installed in the correct clocking and position - this is the correct installation for HEI. There is nothing wrong - it's perfect.
Lars
The photo in your first post shows the distributor perfectly installed in the correct clocking and position - this is the correct installation for HEI. There is nothing wrong - it's perfect.
Lars
Last edited by lars; Feb 9, 2015 at 01:04 PM.
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The #2 cylinder is on the front of the engine.
Le Mans Master
Joined: Jul 2006
Posts: 8,117
Likes: 104
From: charlotte north carolina
I think there is something weird about HEI distributors. The exact firing time is different than a points unit. If you switch from one to another, the rotor is in a different position.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
The rotor will be past the number 1 terminal by the amount of degrees BTDC (Before Top Dead Center) that your timing is set without any mechanical or vacuum advance.
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
At TDC (0 degrees), you are way past the firing point, and the rotor will not be pointing to #1. If the engine times fine, there is no issue.
The photo in your first post shows the distributor perfectly installed in the correct clocking and position - this is the correct installation for HEI. There is nothing wrong - it's perfect.
Lars
The photo in your first post shows the distributor perfectly installed in the correct clocking and position - this is the correct installation for HEI. There is nothing wrong - it's perfect.
Lars
As you diverge from stock, you may find the need to adjust BOTH your initial crank timing +/- AND advance timing to compliment your changes. As an example, with my warmed over, low-compression L48 with improvements, I get away with initial crank timing of 12 BTDC. That means, my rotor will just about point to the #1 spark plug tower with the crank mark at 12 degrees BTDC. My engine is in its sweet, low-compression spot with this plus its total advance settings.
Last edited by TedH; Feb 9, 2015 at 06:11 PM.