Solid pushrod conversion

Top End (cylinders pushrods etc.)
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jarhead
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Solid pushrod conversion

#1

Post by jarhead »

Picked up a new hydraulic lifter conversion kit with 7/16 aluminum pushrods. Didn't realize but my old adjustable aluminum pushrods have a bigger diameter. 1/2 inch. Does this matter? Or were the bigger pushrods for the older style "welch" rocker arms? To install the new adjustable rods is it necessary to remove the cam, lifter blocks and lifters? I know it was discussed to get rid of the springs that come with the kit but why would they designed to go in there? Just in case of a catastrophic failure? Appreciate all replys.
FlatHeadSix
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#2

Post by FlatHeadSix »

jarhead,

I'm an army guy but I'll gladly give advice to a jarhead, my Dad was a Marine and one of the few survivors of Iwo Jima, I'm living proof!

Here's what I understand about juice lifters. I have an almost completely stock '49 that came with the "oil can" hydraulic push rods. The early systems, '49 - '53, are an easy conversion to solids, back the adjustment off far enough to pull the old rods and replace them with solid push rods. Adjust them correctly and you're back in business.

Hydraulic lifters are a completely different animal. They depend on oil supply to make them work and that requires the correct passages feeding the correct lifter blocks, mated with the matching lifters. It's a system and unless everything works together it doesn't work.

Another thing to remember is that cams are ground specifically for either hydraulic or solid lifters. The ramp on the cam is unique for one or the other. If you try to run solids on a cam intended for hydraulics or the other way around, something is going wear prematurely. Either the roller lifters or the cam are going to break down.

This probably wasn't much help. I guess what I'm trying to say is that you should replace everything as a "system"; cam, lifters, lifter blocks, and push rods. That way you know all the components were meant to work with each other. And make sure that the block is set up to supply oil in the right places.

"army" mike
VT

#3

Post by VT »

The conversion process is detailed in Vol. 1 of our book. Order it used if you like from amazon (pssst...it isn't "used" at all) or through vintagetwin.com/ (if you do, then let me know in the email that you bought it through Hydra-Glide.net [HGN] and we'll donate "a buck" to the site's upkeep.)
Or, just use Colony's pushrods and conversion kit. The reason we say remove the springs under the tappet cap is because the springs allow the tappet cups to change positions and possibly lash. When the conversion tappets cups were new, we took a Q-Tip and cleaned the tappet bore with brake cleaner, then used two drops of Loctite (red) to glue the cups. This kept the tappet cups glued for awhile, but I soon noticed that the Loctite released it's grip and the cups spin now. Still, you don't need the springs under the tappet caps. I ran my conversion pushrods under the old '48 removable rocker arm cups for 30K + miles, no problem. But, you want the pushrods and conversion kit as a whole Colony kit. I really like adjusting finger spinning my pushrods at every oil change. My motor talks to me this way.
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