Hi all, a few years ago I was gifted a 1985 GSL from my dad. He let it sit for awhile but I was able to nurse it back to drive-able with some help. A year ago the tach started jumping at idle and I had inconsistent power at temperature. It seemed to run better when choked. Now, it tries to start after pumping but won’t run. I changed plugs but that’s it. I’m thinking maybe the ignition, or timing, but really have no idea where to start. Thanks in advance!

 

Having to pull the choke tells me there could be a vacuum leak. Try spaying some brake clean around the carb and rats nest but not down the carb. If the idle jumps, inspect the area sprayed for a broken hose.

it could be timing, but there isn't much adjustment. If the leading ignitor went out, it could cause a no-start. Most of the time a trailing ignitor isn't even noticed when it goes except for the tach not working.

Try the brake-clean first. It' a non-intrusive thing. Also check for spark on the leading and trailing plugs (one at a time).

 

Thanks for the tips... I finally got around to checking for spark one wire at a time. Isolated the problem to wire one. Replaced all wires and it fired right up. Amazingly, my tach is steady now and my power is back. I think anyone with a bouncing tach should start w new plugs and wires. Thanks again!