Hei replacement

wslonger

New Member
Ok so 2 days ago my '84 would not start at all, I traced it to the Ignition control I went and got a HEI for a chevy truck got it installed and it makes a nice bright blue spark now but the engine just backfires and carries on. The real question is could the HEI have caused a timing issue ? It backfires and carries on like it is out of time. The plug is pretty old and worn so I am going to change it do I use the stock plug type or should it use a different type with the new ignition?
 

Nubs

Cartaholic - V.I.P.
there is no timing difference between the two, if i remember right
rolleyes.gif
if you switch the two leads from the pulsar coil on the HEI it may run better. its been a long time since i did a two stroke.

make sure the HEI is grounded
 

wslonger

New Member
Swapping the red and blue lead from pulser coil made it worse it didn't even attempt to fire with them switched, going to change plug tomorrow getting too warm out already tired of sweating.
 

wslonger

New Member
No good with new plug same situation backfiring and carrying on, I cleaned the carb to make sure it wasn't a fuel issue even though it will eventually fuel foul the plug after a few times attempting to start. I got it to start and somewhat run by closing the plug gap to about .010" The motor got very hot very fast running like this and the plug turned very black leads me to believe it is a timing issue. Anyone have info on timing the pulser coil on a '84 ezgo?
 

wslonger

New Member
I pulled the fan shroud and found timing marks on the flywheel, checking the timing I found that the timing in the forward direction was advanced very far in reverse it was retarded. I didn't change the ignition coil could this be the cause of the timing change?
The original coils resistances are within tolerance for the Ezgo ignition box but may not be good for the GM HEI.
 

dieselmax

New Member
hi i;m new here but i thought i read somewhere that if you use an hei ignition you need to use an hei coil also
 

wslonger

New Member
It appears the HEI doesn't like the original pulser coil, I got a pulser coil from a Yamaha motorcycle, installed and re-timed and it starts and runs great. The original pulser shows correct ohm reading and puts out .6 VAC cranking
 

vintageozarks

New Member
To who ever figured this out Many Thanks My Buggy has been setting for about a year. Because of no way to test the EZ module, Being a semi retired auto mechanic I had the GM HEI module for test purposes in stock wired it up & !!!!! BIG TIME FIRE !!! at plug & Away we go the GM way Thanks again Larry@vintageozarks,com
 
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