Problems installing new pushrods!

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Hi Carl,
First, per Harland Sharp instructions, no more than 2-3 threads showing ball side of stud max, not ideal. You will break it off and also screw up your pushrod geometry. Second, forget about feel. Use actual measurement as in post #12-#13-#21 with chart in post #24 from top of lifter plunger to snap ring. No matter whose hydraulic lifter that clearance/preload is .050-.080 and will
cover any thermal dimensional change, block/heads/pushrods. No need to adjust like a chevy again, ours stay where you adjust them ;-). All hydraulic lifters work the same way, flat or roller. Anti-pump up just has more clearance from plunger to body to
bleed a little faster. Run to heavy oil viscosity and they loose there advantage.

In your picture it seems you bottomed the lifter plunger and are holding the valve open, or your pushrods are to short. Lifters
without oil take .200 or more to bottom out and the pushrod will finger spin until they hit bottom then you preload the valve
open. If that is what happened then your pushrods might be OK. Measure/Measure/and Measure again, install in car and
whoopa##. Feel/feel/twist twist slap slap and all you have is brand x. ;-) Just poke'in fun, they all run with the right attention.

Rick
 
Man after bending a rod, then snapping one off due to over revving, I bought a better quality set from Manton based on measurements of the ones that I know fit. I’m getting frightened reading this thread and wonder if I should just leave well enough alone.
 
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Nothing to be frightened of in this thread, a lot of good information on how to set up the most forgiving of valvetrains.
Assembling it several times without checking a couple easy measurements is very expensive.
Think of it this way. 1 machine shop, 1 person machines your block another decks your heads, another the valve job,
another the crank. None of them a trained general machinist not cnc, most of those are just operators. They are just
operators of a dedicated job machine at your engine machine shop. I am not generalizing here as there are a lot of
outstanding steller machine shops but they are not the majority. I retired from the manual machinist trade as a
master grade machinist of over 40yrs, I have a deep understanding of both trades.

Then you source parts from another 12 manufactures. Then you put it all together and hope everything works with
everything else. I my self don't realy like those odds, I prefer to check.

The information and guidance on this site is way above average, outstanding realy. It's always your choice to bolt
something together and assume it is ok.

Enjoy your evening everyone,
Rick
 
Rick
Yes it believe what I did was tighten down on the lifters which were low on oil vol until they bottomed out. I’ll be sure to look at the number of threads showing after following the correct procedures. 2-3 being ideal for the adjustment.

I also want to thank everyone that has shared valuable information through this thread. It has given me such a better understanding of how the heads and valvetrain function. Without the guidance I would never be able to accomplish this on my own in my garage.
Carl
 
Hi Carl,
Glad I was able to help. Just remember that 2-3 threads out is max. Every setup I did for my self or customer engines
with higher end aluminum rockers with geometry fixtures, the threads almost always ended up flush to the arm surface
on the under side or very near. Longer push rods and you are on the other side of the sweet spot and run the risk of the
cup hitting the arm surface, shorter rods and you will break off the balled adjuster and be on the other side of the sweet
spot. 1.6 ratio rockers stress the adjuster even more, as it moves the fulcrum point closer to the center pivot point. Your
length window for your push rod is even tighter.

The best way to check if your pushrods are the right length is to start your engine with the valve covers off. Watch your
pushrods at the rocker arm. If they move closer to the rocker shaft and away as they open and close the valve they are to
long or to short. They need to go straight up and down for correct geometry. Think about it, if the top of the rod is moving
back and forth that is why you bend/break pushrods. Worst case can even break the rocker at the shaft.

Take care and never lift,
Rick
 
NITROTRIP said:
Watch your
pushrods at the rocker arm. If they move closer to the rocker shaft and away as they open and close the valve they are to
long or to short. They need to go straight up and down for correct geometry. Think about it, if the top of the rod is moving
back and forth that is why you bend/break pushrods. Worst case can even break the rocker at the shaft.

Rick
Click to expand...
This has got to be the simplest and best advice ever given (here) for pushrod length. However I would not do it with the engine running. You can easily see this motion by turning over the engine with the starter. Or even by measuring from a reference point while tuning the engine by hand... which is how I'd do it.
 
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