Timing Way Off

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goodnigh

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Location
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My Car
1971 M-code Grande
So we got the new battery and starter installed. Works fine.

We noticed the car was running a bit rough, fiddled with the

carb a little and checked the timing. At idle the timing mark

using a light was off the scale. We rotated the dizzy counter

clockwise until it stopped and we could see the mark around

20 advance. What happened? Either the dizzy or the "points"

are bad. I would think replacing the ignition would be easiest

and likely the problem. I think it has an MSD module now.

What say you?

mike

 
Mike cleveland balancers are known for turning in the rubber and being off the mark.

 
It also has a plastic coated timing gear , if the chain gets loose, it will jump timing...usually around 80 K miles or more. Pull #1 spark plug, and the coil wire, put your finger over the plug hole and have someone bump the starter until the compression pushes your finger from the hole...that will be close to TDC...pill the dist. cap off and see if the rotor is close to # 1 wire.

You can also put a socket on the balancer bolt and see how much slack is in the timing chain.

 
Mike cleveland balancers are known for turning in the rubber and being off the mark.
Click to expand...
The problem developed overnight and

has not worsened.

My mechanic's first concern was the

dizzy skipped a gear.

mike



It also has a plastic coated timing gear , if the chain gets loose, it will jump timing...usually around 80 K miles or more. Pull #1 spark plug, and the coil wire, put your finger over the plug hole and have someone bump the starter until the compression pushes your finger from the hole...that will be close to TDC...pill the dist. cap off and see if the rotor is close to # 1 wire.

You can also put a socket on the balancer bolt and see how much slack is in the timing chain.
Click to expand...
Engine is rebuilt with maybe 3000 miles on it.

Good point, pull #1 and set TDC. See where

rotor is pointed. Excellent!

mike

 
Last edited by a moderator:
electronic ignition can go wacky overnight, happened to me. car running fine, park it, next day start it, smoked like crazy would not idle or sound right.

because it is an easy swap go back to points and see if the car is normal again.

the balancer is known to slip, but even if it did slip the original timings should of held the next day.

plug the advance and swap in ignition points and condenser and see if the timing holds.

I had 2 petronix ignitions go bad, one was defective magnetic pickup, other was some kind of internal failure.

i think you mentioned you installed a petronix III.

go back to points to weed out issues. if it still isn't right, then could suspect something more serious happened.

also double check ignition wires are solid in the distributor and the plugs. I once had a ignition wire on 1 spark plug magically loosen and it threw the entire engine out of wack.

 
electronic ignition can go wacky overnight, happened to me. car running fine, park it, next day start it, smoked like crazy would not idle or sound right.

because it is an easy swap go back to points and see if the car is normal again.

the balancer is known to slip, but even if it did slip the original timings should of held the next day.

plug the advance and swap in ignition points and condenser and see if the timing holds.

Your post arrived too late. Already ordered a

I had 2 petronix ignitions go bad, one was defective magnetic pickup, other was some kind of internal failure.

i think you mentioned you installed a petronix III.

go back to points to weed out issues. if it still isn't right, then could suspect something more serious happened.

also double check ignition wires are solid in the distributor and the plugs. I once had a ignition wire on 1 spark plug magically loosen and it threw the entire engine out of wack.
Click to expand...
Your post arrived too late, already ordered Petronix "points".

This will be the second time I have replaced the "points". Car

had points that the owner replaced with "points" because he got

tired of the points sticking together. This will be the second time

I have replaced the "points" since I bought the car.

"Points" will be here tomorrow, ordered from Summit Racing and

always next day delivery.

When points go bad, they go bad gradually and not overnight like

"points".

mike

 
Since you had a rebuild 3k miles ago you probably had a true roller timing gear/chain installed. And since you changed the battery and starter and then began seeing rough running i would check wiring of the starter and check your ground. Did you change the battery cables too? MSD's need a solid ground. Check the starter wiring again. Hate to say it but if the key was left on for more than a minute during the swap you could have done damage to the coil. It happens all the time. As for the timing, im betting it was fine. You gotta pull the advance hose, plug it, and dont forget you are supposed to have sombody in the seat, foot on the brake, trans in drive, and the lights on. Wait, the car in gear and lights are for setting the idle speed. Ha!

 
Last edited by a moderator:
If you mean you are replacing a petronix electronic ignition module for another of the same then we are not talking about points and a condenser. You can still order one I keep a set in my trunk for when the electronic one fails. You can try the local auto store and grab a points and new condenser it should be like 20$.

You should still have a back up if you do have a bad ground or you keep fring ignition modules.

 

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