| Rebuilt Engine Information >> LOOSENING OF CRANKSHAFT PULLEY |
Installation Of Crankshaft Pulley To Prevent Loosening On Chevrolet 4.8L (292 CID)
It has been reported that, in many cases, the heavy crankshaft pullet on Chevrolet 6 cylinder 292 CID engines comes loose. A two-groove original equipment pulley, No. 3857352, reportedly gives considerable trouble because of outer hub separation from the rubber vibration damper. A three-groove replacement, No. 3890230 has been recommended.
The crankshaft hub diameter is 1.247 while the ID of the pulley is 1.245, providing a .002 interference fit. Driving the pulley on to the crankshaft causes a distortion to the inner pulley hub causing it to work loose. A proven method if installing this three-groove pulley to prevent loosening is asfollows:
1. Polish crankshaft nose. Do not reduce diameter more than .0005.
2. Heat pulley in boiling water until hub has reached water temperature.
3. Slide pulley on to shaft. No heavy hammering should be necessary to seat the pulley.
4. Place Loctite on the retaining bolt and torque to 65 lbs. Rap the bolt head ad recheck torque.
CAUTION: Check thread condition of retaining bolt before reusing. Also, mark keyway location on pulley before heating to facilitate alignment of key and keyway while handling hot pulley. For safety wear protective gloves. The AERA Technical Committee
July 1972 - SPB 7
##END##
Looking for replacement engines? Visit our online Rebuilt Engines Store.
Need to fix your engine? Access here the comprehensive online repair guide for your engine.
Click Here to find a used engine.
|
|