Similar to the wont run once warm post

[jdsledsrgr8]

Spent the past 2 days up in Price County WI doing some trail riding. Trails were in great condition. Saw very few sleds which surprised me. My 440 Cyclone ran great, however similar to a recent post, I noticed that after riding for an hour or so when I would stop at a stop sign and visit with the guys, my sled did not want to idle and wanted to die. Then it was pretty reluctant to restart. It would restart and off we would go but still it sort of concerned me what was going on.

Engine ran great, had plenty power and fuel efficiency was your standard 40 miles per 8 gallons.

Is this something others have occur? It would not occur right away on the trip, I would say after a good hour or 2 hours of riding it would start this. When we did stop at a bar for food and it sat for a good 30 mins or so it would fire up right away and sit there and idle all day. It only occurred when the engine was warmed up after some serious riding and when we stopped it wanted to die and then to restart it right away it took a good many cranks to finally get back going.

Appreciate your thoughts?

[DLDeere]

I have very similar issues with my 400 and 300.

[Don O]

chech this post
http://www.jdsleds.com/community/viewto ... f=5&t=2473

Don O

[DLDeere]

Good article on spark. When I have this problem I still have spark. I still think it's a carb problem but don't know what.

[harleysportster]

Spent the past 2 days up in Price County WI doing some trail riding. Trails were in great condition. Saw very few sleds which surprised me. My 440 Cyclone ran great, however similar to a recent post, I noticed that after riding for an hour or so when I would stop at a stop sign and visit with the guys, my sled did not want to idle and wanted to die. Then it was pretty reluctant to restart. It would restart and off we would go but still it sort of concerned me what was going on.

Engine ran great, had plenty power and fuel efficiency was your standard 40 miles per 8 gallons.

Is this something others have occur? It would not occur right away on the trip, I would say after a good hour or 2 hours of riding it would start this. When we did stop at a bar for food and it sat for a good 30 mins or so it would fire up right away and sit there and idle all day. It only occurred when the engine was warmed up after some serious riding and when we stopped it wanted to die and then to restart it right away it took a good many cranks to finally get back going.

Appreciate your thoughts?

Not sure what year your Cyclone is, it was not uncommon for the 76 ignition system to fail once the engine got hot. The CDI box would short internally and or the Stator would short out as well. Your symptoms were an early sign of complete failure down the road.
If you have an in-line spark tester, take it with you and check for spark at your next failure.

[jdsledsrgr8]

Thanks for the info Harleysportster. It is a 76 cyclone. It has a Hewitec CD and a NOS stator that I put in a year ago with a complete engine overhaul. I sure hope spark failure is not in my future.

If failure does occur what does that mean? What things can I do to correct today as preventative? I do have another new stator that I could put in if you think that would fix the problem. I can not imagine it is the Hewitec CDI but maybe it has something to do with that. I can email this to Scott at Hewitec to get his thoughts?

On the carb issue one thing that bugs the mechanic that works on my machine is the way the engine sits the carb going into the air box sits at a bit of an angle. The mechanic is a really sharp guy and he has fooled around with it and has it sitting pretty level but still there is a little tilt that bugs him. I would not think this would be causing this issue when it gets hot.

[jdsledsrgr8]

Found time today to go to my trusty mechanic to test to see if ignition failure was a possiblity.

Orginal post was that I noticed after riding my 1976 440 Cyclone for 20 miles or so, it did not want to idle and wanted to die when I would stop at a stop sign. If I did let it die, it would be real reluctant to start back up. If I let it sit for a good 20 minutes or so it would fire right up and sit there and idle all day.

The suggestion was to consider it as early signs of ignition failure, possibly the stator going bad. So it was suggested to test the ohm when cold and then when hot. If the ohms went down when hot then I could have a soon to be issue with the stator or CDI.

I also ran this by Scott at Hewtec and he suggested the same thing. He thought it might be the stator because I was using one of his CDIs and it was basically new and wired correctly.

Engine cold. One wire tested 44 and the other 360. I know these numbers do not match the numbers I was told should be in the range but the mechanic thought it might because he was using one of the new ohms readers and could possibly give different readings when testing older electronics. Still to test we felt the values were relative, the point was to see if they went down.

Went out and rode it hard for 10 miles. I really let it eat. Got back to the shop and it would idle but the mechanic thought like it sounded like it was loading. We immediately tested. The one wire that was 44 cold now tested 66 and the other wire that was 360 cold now was 620. The values went up certainly not down.

So now my question is. Does that make sense for values to actually go up when hot.

We concluded that I do not have electrical issue and we fooled with the carb a bit and everything seems great.

Group thoughts?

[harleysportster]

first off, the meter is set in the wrong range. The ohm reading will be the same if using an old analog or a newer digital style.
The low speed windings should be 2.7K ( thousand) with a 10% tolerance. Try opening the throttle slightly when it won't restart.

[400brian]

My '74 X8 will do much the same thing. I've come to the conclusion that it is a vapor lock issue.
Worse on warm days, on last years Vintage Challenge when I blew a hole in the exhaust, I had the problem so bad I had to keep tossing snow in the engine compartment to make it run. After stopping to replace a belt, I had to squirt fuel in each plug hole to get it to restart.

The X8 has a firewall that originally was insulated, I'm going to see if I can replace it, and review my fuel line routing to see if I can find a cooler path.

Something to think about.