89 Fj Running Issues

[chefmatt]

Hey fellas......Okay, so about a week ago I put my 89 up for sale. Ran absolutely perfect. Until.....the first buyer showed up. She sat for two days on a tender with new battery. Did the usual start up routine, a little choke and cranked. Starter spun and it would sputter, trying to start, but nothing going. Thought water had gotten into gas, we had a huge rainstorm the night before. I drained the tank and bowls, put in a fresh gallon. Still nothing. Starter spun, it would barely catch and rumble but no go. Pulled the plugs, checked for spark and found weak fire on cyl 1 and four. Plugs back in, starting fluid in the carbs and I got it to idle with full choke but any throttle would kill it. Discovered that 1 and 4 headers were cold. Changed 1 and 4 plug wires, cylinders are now firing. At one point, we had it hooked to a vacuum tester (the no 3 cylinder is reading low), I was revving it and at about 5000 rpm it just stalled, as fast as if I hit the kill switch. It take throttle, idles rough as hell, lopes, also backfire.s, which has never happened. This is a sudden issue, all of the shit happening at once. Other symptoms are a rattle from the timing chain before it dies from low idle speed. I mean WTF. This bike has been a horse all summer, run great, and literally as soon as I put an ad up it doesn't run.

Throw some ideas at me if you would. I have had it up for sale for 2100, no interest, then 1500, got some hits. At 1200 alot of folks want it, but my girl isn't rolling. I am about ready to part it out, the need to sell is that bad. Thanks in advance guys. Matt

[Pat Conlon]

You mentioned that it rained the night before...was she left out in the rain?

You know that #1 and #4 fire from the same coil, so I would start there.
Open up the ignition cover, look for moisture, look for a reason why that left side coil is not firing.

[chefmatt]

Thanks Pat. Didn't check for moisture, but the ignition coil is now firing the 1 and 4. The resistor wires weren't reading correct ohms on the two cylinders, and after swapping them out with a different set, they are firing. The problem seemed to move to somewhere else, if that makes sense.

[Pat Conlon]

Ok, then if she has good spark I would move on the fuel side.

Often the idle circuit pickup is the first to plug from debris. The opening at the bottom of the carb fuel bowl gets clogged, clean that....then move on to the pilot jets....pull them out and clean them.

[chefmatt]

Thanks, pulling the carbs is next on the list. Any thoughts on the rattle from the timing chain? Only happens when the motor is dying from low idle...

[Pat Conlon]

That would be the starter chain rattle...very common at low RPM's, it sounds bad but it is nothing to worry about...set your idle at 1,000-1,100 rpm and you will never hear it again.