2005 Ski-Doo Tundra, Skandic, Expedition Shop Manual, Page 51Get this manual
Section 02 TROUBLESHOOTING GUIDE Subsection 02 (ENGINE (4-TEC))
Symptom: ENGINE SUDDENLY TURNS OFF(cont'd)
6Melted andor perforated piston dome; melted section at ring end gap- Spark plug heat range is too hotInstall recommended spark plug (refer to TECHNICAL DATA)- Coolant less than recommended level (engine gets too hot)Repair cooling circuit andor refill with recommended liquid- Poor quality andor wrong fuelClean from contamination and use appropriate fuel (refer to TECHNICAL DATA)7Piston color is dark due to seizure on intake and exhaust sides- Cooling system leaks and lowers coolant levelTighten clamps or replace defective partsAdd antifreeze in cooling system until appropriate level is reachedReplace damaged parts- Oil nozzle is clogged or bentClean or replace oil nozzle (refer to LUBRICATION SYSTEM)8Cracked or broken piston- Cracked or broken piston due to excessive pistoncylinder clearance or engine overrevingReplace pistonCheck pistoncylinder clearance (refer to CRANKSHAFTDRIVE GEARS)9Check piston rings and cylinder surface for grooves- Poor oil qualityUse recommended oil- Contamination through engine intakeReplace defective part(s) and use new air filter10Check valve springs exhaustintake- Broken valve spring damages the cylinder head, valve(s), rocker arm(s)piston piston rings and connecting rodReplace defective part(s)11Check crankshaft, rocker arms movement- Oil pump failure due to leack of oilRepair and replace defective parts and use recommended oil- Oil contamination due to clogged oil filteroil sieveReplace oil and oil filter at the same time,replace defective part(s) (refer to MAINTENANCE CHART and LUBRICATION SYSTEM)