roller rocker preload

Superloop

Registered User
Hey everybody I'm in the process of assembling my engine and wanted some info on how to properly adjust the rocker arms. I have 1.73 stud mount rollers. Thanks!
(Dalke explained it to me, but I'm still confused:rolleyes:)
 
I typically go to zero preload then add a half a turn. If using pedestal style rockers you will need to use shims on the underside of the pedestal and determine which ones to use that will get you to the correct preload. If you are using a custom cam you may need a different pushrod. If that is the case use a pushrod checking tool and check all 12 lifters. You will need to rotate the engine to insure each cylinder for which you are working is at TDC of the compression stroke (the valves should be closed on that specific cylinder when adjusting preload).
 
The problem with zero lash then half turn or whatever is that finding zero lash by eye or feel then addi half turnish is a fairly inaccurate process. If you are off exactly half turn by a couple of degrees or zero lash by a couple degrees then its easy for your adjustments to vary by 5-10 thousandths. Daves method of draining all the oil out of the lifters then using a feeler gauge to set the preload is much more accurate.
 
Thanks for the responses!
I have new lifters completely drained. I'm confused on how to do it with the feeler gauge. Could you elaborate a little more on the process?:eek: At what point do you stop turning the adjusting nut/bolt? and what is the final tightening torque for the lock screw? Thanks
 
I have been building engines for about 25 years. Yes Dave's method is great. I never said it wasn't. It just isn't how I do it. I have developed a feel for this over the years. Additionally I have never experienced any type of valve train failure on an engine that I have built, broken valve spring, bent pushrod, broken rocker arm, etc. There isn't much of a science to it. You should be able to quickly tell when a cylinder is at TDC on the compression stroke with a valve cover off. Even if you are off by a lot the valves are still perfectly closed and as long as both lifter are riding on the heel of the cam then you can set preload. Heck you can also use a dial indicator to set preload. I am also an ASE certified Master Tech (not some kid from the street or back yard mechanic)

As with any goal there is more than one procedure on how to get there. I have owned 4 SC's and worked on countless others. My last SC build had over 300HP at the wheel and the the gentleman who bought it (over 8 years ago) has been taking it to shows, etc. and has never had to pull off a valve cover (custom grind cam too I might add with .573 lift and 216 degrees of duration @ .050). In fact the only thing he has had to do is replace the starter motor. that's not too bad in 8 years. I haven't been around in a while but I will be on a lot as I have recently purchases another SC that I plan on building up. They are fun cars.

I only ask in the future that before you wish to try and put someone down you know who it is you are speaking to. I have a great deal of respect for all of the members and I remember Dave from back in the day when I used to be on here fairly often. Yes he is what I would call an expert.

My ASE# is 5290-2242 if you care to do any research. I also teach automobile technology part time, I worked at a Ford dealership for many years, was a crew chief on a sponsored Harley Drag team for 3 years, am very well respected in the industry. You can call Tony Figga, who is a legend in Southern Jersey, and I am certain he can validate my credentials.
 
i've built quite my share of engines as well, and i can honestly say, i've never spun an engine to tdc on each cylinder to set the rockers ;)

i turn until i feel confident that its where i want it at, spring loaded or not :D

never an issue, its not that detrimental, we have some folks that only use 1/8th turn and others that use a full turn, its not going to make or break anything so long as the valve seats and the rocker stays on the tip


now don't get me wrong i don't recommend that method unless you have developed a feel for your own, im just stating that there's more than one way to do it
 
Im not who you think is putting you down....but its definately not me...you really need to chill out we are each just sharing our experiences....not putting your opinion down.

With the feeler gauge method as you tighen down on the adjuster nut slip the feeler gauge between the valve and the roller....eventually you will find a point where you can no longer insert the feeler gauge....at that point lock it in and ypu are there. It pretting interesting how a few degees of adjustment will make the difference begween being able to insert the feeler and not. Im sorry for not typing in a better procedure but i am on my phone.....a search should turn up a more detailed description.
 
superloop, spin the engine until you see a rocker start to come up and another go down, now hand tighten all the other rockers until they are snug, wiggle the rocker to make sure its not just the threads binding, speaking of which you should be using either a thread paste, oil, or thread locker on the threads, one you've got all other 10 rockers hand snug, put a half turn on them and your there, you can now tighten the lock nut, now spin the engine until the other two rockers are down and two others are in motion, now do the same process for those two.

/done

if you have any issues give dave a shout, im sure he wouldn't mind going over it with you one more 'gin
 
I gave the OP my phone number to call with any questions but I have not received a phone call or email asking for further assistance. There are specific reasons for the adjustment procedure I outlined which I do not wish to get into here. My phone is on and I am available to answer questions. I can also address specific questions via email if that is preferred.

Thanks,

David
 
I used the Pick up the PHOne and call up Dave to get the instructions over the phone method. Seems to work out ok its not brain surgery as I though prior to the call. :eek:
 
Hey everybody I'm in the process of assembling my engine and wanted some info on how to properly adjust the rocker arms. I have 1.73 stud mount rollers. Thanks!
(Dalke explained it to me, but I'm still confused:rolleyes:)

I just watched Dave do this! Call him and let him explain it to you. Not hard at all as long as you read the feeler gauge right :D
 
Thanks for all the replies. Dave had to explain it to me once again and I finally understood how to do it right.
 
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