Whoa Timing Off - Need some input
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Whoa Timing Off - Need some input
Just checked the timing.
The Spec for this engine is 12 initial and 36 total.
With the vacuum advance disconnected, and my Idle RPM @ ~850... my initial timing is reading 36.
This is as far as I got. I stopped here and didn't figured I'd see if there are any obvious reasons for this.
I didn't know you could advance the initial timing by that much... can you?
Does this sound like the advance springs need to be replaced?
In case it matters, the timing light wires dont reach the battery, so I connected to the alternater.
Ok... go!
The Spec for this engine is 12 initial and 36 total.
With the vacuum advance disconnected, and my Idle RPM @ ~850... my initial timing is reading 36.
This is as far as I got. I stopped here and didn't figured I'd see if there are any obvious reasons for this.
I didn't know you could advance the initial timing by that much... can you?
Does this sound like the advance springs need to be replaced?
In case it matters, the timing light wires dont reach the battery, so I connected to the alternater.
Ok... go!
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
As long as you have 12V it doesn't matter where you hook the leads. Make sure you're on #1. Does the timing advance when you blip the throttle? If not, you may have lost one or both springs on the timing weights.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Is it possible for it to be advanced this much and still run? And all I need to do is retard it?
Melting Slicks
Joined: May 2002
Posts: 2,716
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From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Its not uncommon for the shaft to gum up and stick, it may be stuck at full advance.
Neal
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Melting Slicks
Joined: May 2002
Posts: 2,716
Likes: 121
From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
should be very hard to start,
Neal
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
Not hard to start. A few pumps of the gas and it usually starts right up when it isn't cold. When cold, it's a little rough for a few minutes until it warms up... but still it starts without too much issue.
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Instructor
Joined: Mar 2013
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From: Sunshine Coast Qld
So by MSD transistor ignition, do you mean you have a 6AL type ignition box? If so, are you using a dial back timing light? MSD warns against using dial back lights as you may get a false reading. If that's what you have of course.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
The MSD box says 6A...doesnt say 6AL that I can see. Not sure if there is a difference. The timing light I have is digital.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
So.... should I assume a false reading from the light? weird that it is false reading exactly what the total timing 'should' be.
OR
DO I try to retard the timing down to 12. Do I risk breaking something in doing this?
OR
DO I try to retard the timing down to 12. Do I risk breaking something in doing this?
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
At this point I would pull the cap and rotor off to inspect the advance weights. If the springs are on there , see iff the weights move freely. Then I would get a thick rubber band and put it around the weights in a manner that allows the distributor to turn but holds the weights from opening at idle speeds. Basically, lock out the mechanical advance and disconnect the vacuum advance.
Melting Slicks
Joined: Jul 2006
Posts: 2,285
Likes: 487
From: Salmon Arm, BC
I agree that it should be harder to start with that inital setting. It sounds like it starts just fine by your explanation....so I'd borrow a buddys timing light to cofirm or dispell this. Have a look at your balancer and see if anything has slipped or out of place as well. MSD will have something on there site about checking timing properly with that ignition system.
Racer
Joined: Jan 2010
Posts: 261
Likes: 4
From: Albuquerque Resistance is not futile. It's voltage divided by current.
"How do you "un-gum" it. If I find that is is gummed? How will I see this?"
Take the distributor cap off and see if the rotor moves freely clockwise and springs back when you let go. (I think cw, I dont
have a dist in front of me.)
If it moves freely and springs back, replace the cap and retard the timing, turn dist clockwise. You'll have to increase idle speed as you retard.
If rotor does not move or does not spring back freely, further
inspection of dist is required.
In other words, take it out, take it apart and have a look.
It'll help you understand how it works.
Is the dist GM point style? HEI? MSD? Other?
Also be aware of timing tapes you can get for the balancer,
to take dial back error out of the equation.
Let us know what you find.
Good luck, GA
Take the distributor cap off and see if the rotor moves freely clockwise and springs back when you let go. (I think cw, I dont
have a dist in front of me.)
If it moves freely and springs back, replace the cap and retard the timing, turn dist clockwise. You'll have to increase idle speed as you retard.
If rotor does not move or does not spring back freely, further
inspection of dist is required.
In other words, take it out, take it apart and have a look.
It'll help you understand how it works.
Is the dist GM point style? HEI? MSD? Other?
Also be aware of timing tapes you can get for the balancer,
to take dial back error out of the equation.
Let us know what you find.
Good luck, GA
Racer
Joined: Jan 2010
Posts: 261
Likes: 4
From: Albuquerque Resistance is not futile. It's voltage divided by current.
and lessen the load on the starter.
GA
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
You shouldn't have to pump the gas when it isn't cold. However, an engine with advanced timing or weak starter may hot start easier with a few squirts. When hot, a few squirts of the acc pump richen the mixture enough to knock down the cylinder pressure a few revolutions
and lessen the load on the starter.
GA
and lessen the load on the starter.
GA
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
At this point I would pull the cap and rotor off to inspect the advance weights. If the springs are on there , see iff the weights move freely. Then I would get a thick rubber band and put it around the weights in a manner that allows the distributor to turn but holds the weights from opening at idle speeds. Basically, lock out the mechanical advance and disconnect the vacuum advance.
Thread Starter
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
I agree that it should be harder to start with that inital setting. It sounds like it starts just fine by your explanation....so I'd borrow a buddys timing light to cofirm or dispell this. Have a look at your balancer and see if anything has slipped or out of place as well. MSD will have something on there site about checking timing properly with that ignition system.
