New timing chain loose

[GreenZZZ]

I've got an E31 head on a stock L24 block.  The head probably has 15K miles since a valve job done by Motorsport Auto in the early 90's.  I sent it the head to Motorsport because I wanted a "Z guy" to do the work properly.

Reason I'm posting is I'm putting a new chain and like the last time, the chain is really loose.  I remember with my E88 head it was always a serious effort to get to cam chain on mark "1".  With this head, I go straight to "3" and move the passenger side chain guide to the inner more tight position.  Is this an E31 thing or a sign of an improperly shimmed cam tower??  The towers have one shim on them.  Stock valves which don't hit the pistons.

I bought the E31 off the old ZHome/IZCC forum way way back in the day so no telling how often it has been shaved.  Back when the internet was only good for getting Datsun parts and Grateful Dead tickets!  The head/chain ran great until I spun a connecting rod at Harris Hill race track...

What do you think?

 

 

Edited June 16, 2017 by GreenZZZ
type-o

[240260280]

Good talking!

 

Have a look at the photos here:

 

 

 

Philip

[siteunseen]

For what it's worth mine was cut once since I've owned it to straighten it, can't remember the thousandth though but here's where mine is against the E31 stamp. My machinist told me it wouldn't need to be shimmed?

 

Edited June 16, 2017 by siteunseen

[240260280]

The bottom of the passenger side guide should be further  to the left so that the chain tensioner  is doing most of the pushing at that point.

The bottom of that guide should be tucked in away from the chain so that there is no wear on its leading edge. Take a look at this:

 

[GreenZZZ]

Thank you thank you!

My head looks similar.  Probably got some life left in it.

 

[siteunseen]

Yes! They have that same slant towards the "1". Maybe I will need shims? Thanks for posting that pic.

Hoping for the best on your rebuild.