Cm870 Jake detent worn

[Rawze]

(04-10-2017 )Pete379 Wrote:  On Friday I heard a strange intermittent clanging noise from the passenger side of my cm870 when I parked the truck. Over the weekend I pulled the valve cover and noticed that the jake detent was worn on #6 and the noise was from it not sitting in detent while not engaged. The jake wiring harness also is in pretty bad shape so I plan on replacing that as well.

I was wondering if anyone had any experience replacing the rocker lever shafts and could give and tips or information that might help me when getting into this repair...

MY injector leak-down test series shows the upper end being pulled apart and re-installed.






In this series, I said 70 ft-lbs on the bolts in one of them. It has been found that it is better to torque the rocker shaft retaining bolts to 105 - 110 ft-lbs. I now set them to 95 ft-lbs these days, especially if they have been off a couple times.

reference: http://rawze.com/forums/showthread.php?t...2#pid10802



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and I also discuss them in detail in my re-build series...





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I disagree with the book for setting the rocker shaft positions. It tells that the rocker shaft(s) can be rotated to get the correct clearance between the detent position of the rocker and the top of the valve stem. This is old out-dated information and is not correct. Here is a discussion about rocker detent clearance, wear and getting the rocker shafts in place correctly...

http://rawze.com/forums/showthread.php?t...66#pid9466



Maybe that helps.