97 challenger stalling

[rockytsi]

Hey guys/girls, i'm new to this forum so hello to everyone. I recently bought a 1997 challenger single engine 787. It's loads of fun to ride, but it stalls at start-off. It starts and idles fine, but when I ease the throttle on, it stalls. I have to be very, very gentle on the bottom 20% throttle to keep it going. This is very frustrating. Any suggestions/helpful tips would be greatly appreciated.

Cheers,

Rocky

 

[Bills86e]

Your symptom sounds Electrical IMO But doo a compression test & change *plugs.
Unplug the connector for the lanyard post and clean it, then clean the inside of the lanyard itself. Then try it again. You can also clean, dielectric grease and test all fuses, wire connectors, and grounds, unplug the magneto connector plug and clean it too. Hopefully you just have a corroded terminal somewhere that is breaking contact. Check your lanyard to see it it fits all the way on. A pencil eraser works.
Besides grounds, fuses and fuse holders, the main places to be concerned with are the innards of your coil box, and all igniton related connectors, including the stop start switch and lanyard post, mpem, cdi and coil connector.
Worst case senario is a bad ignition pickup in the magneto housing that may be broken or is covered with metal debris and is getting shorted out. Bills86e

 

[rockytsi]

Changes fuses...tested connections. Spark plugs changed. DESS cleaned. Still stalling on start-off. Maybe carb/rave dirt?

 

[Bills86e]

U bad ignition pickup in the magneto housing that may be broken or is covered with metal debris and is getting shorted out when engine vibrates on take off.

 

[seadooya]

or the carbs need gone thru/excel pump-fittings cleaned out

 

[voodoo]

If you do a search here there is a lot of info on the general nature of fuel system service that applies to any of the 2stroke family, every segment must be in good order or leanout and burnt pistons will result from neglected fuel troubles masked as other problems, begin with a compression test and move along the fuel lines fixing anything that looks like a leak - an air leak is as bad as a fuel leak, if the lines are the grey color ones then plan a day of fuel system service with all new lines and cleaning out the tiny filters inside the carbs, the selectro switch can be repaired by most but a new one is only about 25bux here and will eliminate a tough-to-locate fuel/air leak.

 

[rockytsi]

Hey,

I took it out for a run this evening to re-diagnose the problem so I could post a better description of it on here. Well, now it will only run on one cylinder. It ran the same as described above for the first 20 mins....then only one cylinder and never went back to two. I checked the spark on both sides and they seem ok. I'm pretty new to this stuff so any suggestions would be greatly appreciated.

 

[rockytsi]

Also, the prev owner has it coated with "anti-foul?" paint. I assume this is what it is. (green/grey paint applied to the bottom half of the boat/nozzle assembly. How can I remove this?

 

[rockytsi]

My problem does appear to be electric in nature....
Where is the magneto/housing located and how can I clean it?

 

[seadooya]

install new plugs, clip the plug wires' at boots' ends 1/4in, and clean the raves.

 

[rockytsi]

By boots you mean plug caps? Also, is there anything I should watch out for when I remove the raves so I dont damage or reinstall them wrong?