Crankshaft engine problem Brisbane - WORN OUT
Severely worn out crankshaft journals are normally associated with worn bearings and all the reasons and symptoms are explained under big-ends/mains / worn out. However the incorrect selection of bearings can cause excessive wear of the crank while the bearing shells are reasonably normal. Some cranks must be nitrided during the grinding process and run fairly hard bearings. The introduction of embedded abrasive material can wear the crank pins and journals more than expected leaving the bearings at first glance relatively unscathed. When the lack of nitriding is the suspect cause all journals will generally be similarly affected. Check hardness. The rear main seal area can be severely worn where the seal lip contacts the shaft. This can be the result of hardening of the seal over time. Most shafts suffer this problem and this area can be reground provided the shaft diameter stays within the seal specified shaft size. If this is not possible by grinding a speedy sleeve can be fitted to reclaim this area. A loose front pulley or balancer can also damage the front snout of the crankshaft. Welding and re- machining can reclaim the keyway and snout area. This process also has its problems and all repaired shafts should be crack-tested. Again this process should only be carried out after discussion with the customer. Good service procedures can prevent this problem occurring. Disclaimer Agreement : Every care has been taken in writing this information and procedures, but no responsibility can be excepted for errors, omissions or misuse of this information and procedures. The information available on this site is for your instruction only and cannot be copied for sale, © copyright 2001 UMR Engines
Worn main bearings
and crankshaft
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Queensland Transport Authorised to approve LA1,LA3,LB1,LD1-2,LK1,LK6 Modification’s to light vehicles
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LPG Approved Workshop
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RWC Licence
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RACQ Approved Automotive Repairer
Crankshaft engine problem Brisbane -
WORN OUT
Severely worn out crankshaft journals are normally associated with worn bearings and all the reasons and symptoms are explained under big-ends/mains / worn out. However the incorrect selection of bearings can cause excessive wear of the crank while the bearing shells are reasonably normal. Some cranks must be nitrided during the grinding process and run fairly hard bearings. The introduction of embedded abrasive material can wear the crank pins and journals more than expected leaving the bearings at first glance relatively unscathed. When the lack of nitriding is the suspect cause all journals will generally be similarly affected. Check hardness. The rear main seal area can be severely worn where the seal lip contacts the shaft. This can be the result of hardening of the seal over time. Most shafts suffer this problem and this area can be reground provided the shaft diameter stays within the seal specified shaft size. If this is not possible by grinding a speedy sleeve can be fitted to reclaim this area. A loose front pulley or balancer can also damage the front snout of the crankshaft. Welding and re-machining can reclaim the keyway and snout area. This process also has its problems and all repaired shafts should be crack-tested. Again this process should only be carried out after discussion with the customer. Good service procedures can prevent this problem occurring. Disclaimer Agreement : Every care has been taken in writing this information and procedures, but no responsibility can be excepted for errors, omissions or misuse of this information and procedures. The information available on this site is for your instruction only and cannot be copied for sale, © copyright 2001 UMR Engines
Worn main bearings
and crankshaft
7 Moss Street, Slacks Creek, Qld 4127
