mechanical advance
Thread Starter
2nd Gear Member
Joined: Jun 2006
Posts: 242
mechanical advance
ok just making sure i read this correctly
my 68 with a 289 has had stumbling problems. i checked the timing
it is set at 10 degrees advance with the vacuum lines unplugged.
with the lines still unplugged at 3000 rpms it still reads 10 degrees.
shouldnt the timing go up because of the springs in the dizzy.
its the factory one with a pertronix btw if that means anything
with the vacuum line plugged in, at 3000 rpms it reads 20 degrees
my 68 with a 289 has had stumbling problems. i checked the timing
it is set at 10 degrees advance with the vacuum lines unplugged.
with the lines still unplugged at 3000 rpms it still reads 10 degrees.
shouldnt the timing go up because of the springs in the dizzy.
its the factory one with a pertronix btw if that means anything
with the vacuum line plugged in, at 3000 rpms it reads 20 degrees
6th Gear Member
Joined: Aug 2007
Posts: 5,896
From: Elk Grove, CA
RE: mechanical advance
Yeah, sounds like your mechanical advance is binding and nonfunctional. That, or the springs are weak/broken and it's advanced all the way, all the time. You can usually pick up recurve kits at your local chain parts store. I'd do that and clean it up real good, see what you can do with it.
Thread Starter
2nd Gear Member
Joined: Jun 2006
Posts: 242
RE: mechanical advance
quick question, i am lining up my 0 timing mark to the TDC marker so i can take the distributer out and i have a question about jumping the solenoid on the firewall to move the engine.
large cable from battery. large cable to starter
do i jump the two small wire on the center of the solenoid
or is it the large cable to the starter to one of the small wires.
its been so long since i have had to do this i forgot.
large cable from battery. large cable to starter
do i jump the two small wire on the center of the solenoid
or is it the large cable to the starter to one of the small wires.
its been so long since i have had to do this i forgot.
Thread Starter
2nd Gear Member
Joined: Jun 2006
Posts: 242
RE: mechanical advance
ok 0 degrees on the balancer is lined up exactly at the pointer and the rotor is pointing at #1 cylinder so all i need to do now is pull the old and put in the new just making sure the rotor on the new one is pointing at #1 again right?
6th Gear Member
Joined: Oct 2006
Posts: 6,417
From: Cork, Ireland
RE: mechanical advance
yah. that's the way to go. pointer pointing to #1, engine (crank) on 0degrees. swap distries.
Just a comment on the first post:
yes you're right, your mechanical advance is probably fried, but it's not the springs who make the advance.
It's a centrifugal system. The springs are holding the centrifugal parts back so that you don't have full advance on 1500.
in other words, the springs will try and keep those to weights centered (no addvance), but the higher refsm, the quicker the spindle in the distr turns, the more the force pushing the weights outside, the more advance ...
so if you don't have a new distributor yet, try to free up those 2 weights that work against the springs
Kalli
Just a comment on the first post:
yes you're right, your mechanical advance is probably fried, but it's not the springs who make the advance.
It's a centrifugal system. The springs are holding the centrifugal parts back so that you don't have full advance on 1500.
in other words, the springs will try and keep those to weights centered (no addvance), but the higher refsm, the quicker the spindle in the distr turns, the more the force pushing the weights outside, the more advance ...
so if you don't have a new distributor yet, try to free up those 2 weights that work against the springs
Kalli