Timing WAY advanced, Runs Again!
MooseNelson
04-12-2008, 03:11 PM
Hi there, I posted back a silly thread about having adjusted valve clearance on my rocker arm cam 1992 eagle summit (mitsu 1.5).
So after changing the plugs under heavy throttle, this sickening stutter, like serious backfiring, almost dangerous inability to accelerate.
So today I messed around and finally got the courage to advance the timing by unlocking the distributor and rotating it. moving towards advanced, idle goes way up and under heavy throttle pressure, WAM, straight up the RPMs, no stutter.
SO:
Bought a timing light to look at what is going on. CAM notches line up when crank mark is lined up, so don't think i jumped a tooth.
But this thing stutters like Ron Jeremy when timed to marks (nice little $10 inductive shooter), I have to advance the distro almost all the way, to achieve any unflattened accelerate pressure.
WHY? Is the advance timing compensating for crappy spark?
:dupe:
So after changing the plugs under heavy throttle, this sickening stutter, like serious backfiring, almost dangerous inability to accelerate.
So today I messed around and finally got the courage to advance the timing by unlocking the distributor and rotating it. moving towards advanced, idle goes way up and under heavy throttle pressure, WAM, straight up the RPMs, no stutter.
SO:
Bought a timing light to look at what is going on. CAM notches line up when crank mark is lined up, so don't think i jumped a tooth.
But this thing stutters like Ron Jeremy when timed to marks (nice little $10 inductive shooter), I have to advance the distro almost all the way, to achieve any unflattened accelerate pressure.
WHY? Is the advance timing compensating for crappy spark?
:dupe:
Moppie
04-12-2008, 05:17 PM
It is possible the auto advance has seized in the dizzy.
UncleBob
04-12-2008, 07:32 PM
what moppie is referring to, the mechanical mechanism in the distributor that applies advance is a simple weights and spring setup, as the distributor spins, the weights get flung out and overcome the springs at a set RPM
If that assembly is seized, it won't advance as teh RPM's increase
Simply put the timing light on it and rev it up with vacuum hoses disconnected (if any). You should see a 20 or so degree increase from idle, by 2500-3000 RPM's or so. If it doesn't move at all, it needs a distributor, or you need to rebuild the one you have.
If that assembly is seized, it won't advance as teh RPM's increase
Simply put the timing light on it and rev it up with vacuum hoses disconnected (if any). You should see a 20 or so degree increase from idle, by 2500-3000 RPM's or so. If it doesn't move at all, it needs a distributor, or you need to rebuild the one you have.
Automotive Network, Inc., Copyright ©2025