I rebuilt my LMM for my swap into my 1967 C10. It quickly developed a noise in about 500 miles from the timing cover, a pulsating sound at camshaft speed. I chased the noise for a bit and ended up finding a strange wear pattern on the cam gear teeth. The teeth are shiny and rough, and the pattern shows about 50% of the tooth to about 90% of the tooth coverage going around the cam gear. I was certain this was the noise and put a used nice condition LB7 solid gear on. Most of the noise is gone, but I'm still concerned because the crank gear has the same ''look'' to the teeth, but the pattern is consistent all the way around.
Anyone else ever come across this? It was a LMM from an ambulance with 270k miles, likely lots of idle time. The original cam bearings and camshaft bearing journals were heavily worn. New cam bearings and new Wagler camshaft installed during rebuild. I did not notice the pattern on the timing gears when I rebuilt it and had reused those parts.
I'm having trouble finding a NEW crankshaft timing gear, gm parts shows its only sold as part of crankshaft assembly. Picture of teeth attached.
Anyone else ever come across this? It was a LMM from an ambulance with 270k miles, likely lots of idle time. The original cam bearings and camshaft bearing journals were heavily worn. New cam bearings and new Wagler camshaft installed during rebuild. I did not notice the pattern on the timing gears when I rebuilt it and had reused those parts.
I'm having trouble finding a NEW crankshaft timing gear, gm parts shows its only sold as part of crankshaft assembly. Picture of teeth attached.
