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Discussion Starter #1
This might be a dumb question, but this is the first time I'm assembling a roller motor.

I'm to the point where I've dropped in the lifters and ready to put the dog bones in and bolt down the spider "keeper". Question is, do the dog bones drop in first and the keeper simply sits on top of the dog bones, or do the dog bones go in the space on the keeper's "tangs" and it installs as one assembly.

I guess in other words, should those dog bones have any movement at all when everything is tightened down or should the be tight against the block? I'll attach a pic of how they are currently but I don't think it's correct. The dog bones are really loose and that just doesn't make sense to me that it would work.

Also, does it matter if the oil hole on the lifter is positioned at the top (away from the heads) or bottom (towards the head) in the lifter gallery?

 

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That's a very smart question, as many get it wrong. The dog bones go directly on first, with the little bump UP, and the spider sits fully on top of them with preload. In-effect, the bones 'see-saw' on each end, pivoting against the bottom of the spider feet. The lifter oil hole position does not really matter, though I place them down for no established reason. LOL

David
 

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This might be a dumb question, but this is the first time I'm assembling a roller motor.
The unask question is the dumb one, even though the answer maybe simple for some...
I guess in other words, should those dog bones have any movement at all when everything is tightened down or should the be tight against the block? I'll attach a pic of how they are currently but I don't think it's correct. The dog bones are really loose and that just doesn't make sense to me that it would work.
I am under the assumption that "play" would be bad, not to mention very noisy. The spyder is built to put a bit of 'load' on the dogbones keeping them in place.
Also, does it matter if the oil hole on the lifter is positioned at the top (away from the heads) or bottom (towards the head) in the lifter gallery.
YOUR preference, as David stated. I have never built a roller engine, but if it were mine and me doing it I would point them the opposite of the way David runs his. ( my thinking is it (the lifter) would 'hold' a tiny amount of oil even at rest, when turned down they would drain somewhat due to gravity)
 

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Discussion Starter #5
Answers were a big help! Thanks!

Now about the upper part of the valve train, specifically the rocker arms. Obviously those little brackets are used under the rocker arms essentially connecting the two together. It appears to me that how you tighten the rockers down does not effect valve lash and I'm assuming lash is not necessary on roller motor?

Do I still follow the same sequence for tightening the rockers though, turning the motor over and doing one cylinder at a time or does it really not matter?

If not, what should I torque the allen bolts to that fasten the rocker to the head?

Thanks!
 

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Refer to your manual first. While the rockers on hydraulic cam positive-stop and pedestal rockers is a bolt-down affair (in any crank position), the lifter preload must first be confirmed or established. Your lifters should have .020 to .030 preload on them when fully torqued to spec. This is done with pushrod length and adjusting shims. This preload must be right before torquing everything down.

An easy way to see if it's about right is to set one cylinder to TDC firing position. Then assemble one valve set together (two rockers, pushrods and the channel alignment piece - no oil), and bring the socket-head bolts down to take-up the slack with your fingers while spinning the pushrod with your other fingers. You should have spinning resistance (zero lash) at less than 1-turn remaining, but more than 1/4 turn. This is outlined in your manual.

If the preload is outside this range, the pushrods, adjusting shims, or both will have to be used to bring preload into spec.

David
 

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Discussion Starter #7
I have no manual outlining the assembly of a roller motor, only the flat tappet style.

If there were no shims to begin with, do I need them now?

And what am I actually measuring to determine pre-load.

This is all new to me. I'd rather be doing a flat tappet but this is a favor for a friend.
 

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Roller with pedestal rockers is no different than flat-tappet with positive-stop studs (the previous way the factory did non-adjustable rockers). The goal is to preload the hydraulic lifters (flat or roller) with a tiny amount of compression (preload) when the rockers are fully torqued-down.

With adjustable rockers, you would screw them down until you had zero lash, and then another 1/4 to 3/4 turn for lifter preload, and lock them there. With non-adjustable pedestal rockers it's the same, but you can't do it with adjusting nuts, and instead it's done with pushrod length and/or adjusting shims.

Do you need to change adjustment now? Maybe not, but there is only one way to be sure - check it. If there had been no machining to the block deck height, nor any machining to the head deck (cylinder sealing surface), and they are the same ones used together before - then you're probably OK assuming the originals were set-up right. Again, there's only one way to know, and it only takes a minute to do the check I described earlier.

David

[EDIT] Here is a video clip by Ken Collins (a member here) on doing pedestal rockers. Although these are aluminum roller rockers, they install and adjust the same as any other pedestal type. What you do not see is how he earlier changed pushrod length as part of the adjustment process.
Valve lash adjustment on a 5.0L with pedestal rockers - YouTube
 
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