Topic: primary chain slack

[Druro]

how much slack should there be in the primary chain when assembling.  i have some slack, but i'm unsure if that is a major problem, or not.

btw..  first time building an engine

[screwtheman]

I'm also elbows deep in open heart surgery at the moment. So it was easy for me to check! My primary chains have about 15mm (~1/2 in.) of travel when I press with firm pressure on the top of both chains halfway between the crank and countershaft. According to the shop manual (if you don't have one GET ONE- http://www.helminc.com), you're supposed to measure from the bottom by removing the oil pan and measuring the distance from the bottom of the chain tensioner bracket to the bottom of the crankcase (where the oil pan gasket goes). You're effectively measuring how much the tensioner is pushing up on the chains. The manual says if it's greater than 70mm, then they need to be replaced.


Hope that helps!