Have to lash valves when studding?

[AMassaro]

I'm slightly confused here. When I install head studs, I was under the impression that you must lash the valves afterward. And it makes sense to me since you have to remove some of the rockers which are in the way.



Yet I've read some threads where lashing wasn't required? What gives?

 

[JStieger]

If you are in that far, you might as well spend an extra 30 minutes just for the peace of mind. For grins and giggles I measured valve lash before removing rockers and right after reinstalling rockers and it did change on some about 0. 001" - 0. 002", but most were still the same, although some may argue that to detect 0. 001" difference is splitting hairs due to feeler gauge technique :-laf . It's your truck... if it was mine, I would do it.



BTW good research on the ARP torques!

 

[WCounts]

I would go ahead and do it while you have the valve cover off. Only takes 30 mins.

 

[AMassaro]

Thanks for the replies... I'm still trying to figure out the "logistics" of this... maybe I'm confused because with Chevy V8's or others for that matter, if you removed a rocker arm, the only way to properly re-install it was to set the lash again... . Never having my Cummins valve cover off, though I've seen pics, it must be a quite different type of stud/rocker/valve train... .

 

[WCounts]

Thanks for the replies... I'm still trying to figure out the "logistics" of this... maybe I'm confused because with Chevy V8's or others for that matter, if you removed a rocker arm, the only way to properly re-install it was to set the lash again... . Never having my Cummins valve cover off, though I've seen pics, it must be a quite different type of stud/rocker/valve train... .

Quite a bit differant from chevy rockers. The rockers on the Cummins have a socket screw and jam nut to set the lash and a seperate bolt to clamp them to the head. So you could remove them with out changing the lash by much.

I would set a table be side the truck and keep the rockers in order so you can put them back where they came. You'll be removing all the exhaust rockers and #s 5 and 6 intake. The rest will have to be loosened. Don't forget to notch the lower rocker box where the rear stud makes contact. Easy to see what you need to do.

 

[AMassaro]

Sounds similar to a Jesel setup, if you've ever wrenched on that type of valvetrain... Thanks for clarifying...

 

[jwilliams3]

Quite a bit differant from chevy rockers. The rockers on the Cummins have a socket screw and jam nut to set the lash and a seperate bolt to clamp them to the head. So you could remove them with out changing the lash by much.

I would set a table be side the truck and keep the rockers in order so you can put them back where they came. You'll be removing all the exhaust rockers and #s 5 and 6 intake. The rest will have to be loosened. Don't forget to notch the lower rocker box where the rear stud makes contact. Easy to see what you need to do.

Just a side not but you wont have to notch the rocker box if you bottom tap.

 

[AMassaro]

Gotcha. . and I will.



Justin, your truck sounds really good in your vids. Stupid question though... Is that your clutch that sparks in the darker vids? Never seen that before.

 

[jwilliams3]

Tony,

Thanks!!



Yeah, those are sparks from the clutch. That truck pulling thing is pretty hard on clutches... . You can literally see the money leaving my wallet when I pull at night!!