Running on just 1 cylinder INDY 500 - 1991 Indy CDI ? started by fish6996
	December 30th 2008 at 6:48 PM Post #1
	fish6996 New Member 61 Posts Group: Members Member Since: January 16th 2003 Location: Derry, NH, USA
	Is it possible for one output of the CDI to give a weak spark to the extent that one cylinder will not run. 91 Indy 500 liquid, Getting fuel...Has 120 PSI in both cylinders yet the mag side does not run. I can run the sled and pull the wire off the bad cylinder and it does not die just keeps running on the PTO cylinder Has spark at both plugs with a tester and when just looking at the sparkplug. I cleaned the carb Neeld and seat appears to be function properly. This just started running crappy one day last season as I was heading for home... I was going to tyr to swap out with a known good CDI but the connection are not the same. Is thre a way to actually t est the out put using a meter or something.. any other ideas...or advice out there..? Thanks... FISH 91 Indy 500 Favorite Quotes: I read it on Snowmobile Fanatics ... I'll take care of it... I'll be back in just an hour... Rating: 0 Quick Edit Edit Topic

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	January 2nd 2009 at 7:49 PM Post #2
	STEVE650 future dad 1997 Posts Group: Members Member Since: December 6th 2005 Location: magog, québec, Canada
	try to interchange the wire with the one that is running. I already see a bad plug that just don't spark under compression condition.... for real! Or interchange the spark plug to see if the trouble change place. But I think you have a bad coil that is making a weak spark. There's no way to test a CDI, you have to try another one that you know it is working. Hope it helps! Rating: 0 Quick Edit Full Edit

	January 2nd 2009 at 8:18 PM Post #3
	TeamNFG Advanced Member 1457 Posts Group: Members Member Since: February 22nd 2006 Location: SomeSno, Ab., Canada
	check spark try new plugs if nogo pull the exhaust and look up into the engine with the y pipe off, look for a broken piston skirt, pull the carbs and reeds and if you can see the piston do the same, look for a broken piston skirt. A broken piston skirt will still show compression, but will not pull fuel in to the combustion chamber, resulting in a dead hole. If it all looks good try new plug caps, then new wires, then see if there is a coil you can try. If the CDI is shot you would have no spark at all Good Luck Fix it till its broke! Rating: 0 Quick Edit Full Edit

	January 2nd 2009 at 10:41 PM Post #4
	John_Lennon92 Starting Member 14 Posts Group: Members Member Since: December 9th 2008
	I have to agree with these guys that say try switching out the plugs. I had the same problem with mine. the left cylinder was the only one running. monkey with the carb a bit on the dry cylinder if the piston skirt looks good. you may not have enough fuel going into the cylinder. Rating: 0 Quick Edit Full Edit