[quote=“ctbimmer” post=71804]That used to be the conventional wisdom, but there’s an easier and less-destructive way.
The idea is to take the shaft out the front, regardless of how far you need to go to reach the rocker.
The hard part about sliding the shaft is that it’s impossible to get all 6 valves off the rocker at the same time.
So, the trick is, before starting to remove the shaft, remove all the retaining clips, figure out what your target crank position is (making sure you are aligned to slide the rocker shaft through one of the holes in the cam gear, is to identify the valves that are going to be “up” when you get to your target position.
So, temporarily, rotate engine to move the troublesome cylinders so the pressure is off the rocker(s), and slide them laterally to “park” them in between the lobes. Then, return the crankshaft to desired orientation, and you should have a shaft that can slide without pressure from any of the cam lobes.
The next thing holding you back will be the amount of varnish/crud built on the shaft, making it resist sliding even though there is no valve pressure. YMMV on that one, for sure. With a clean engine, it’s very easy to slide.
Reinstallation is similar. Make note of which rockers need to be parked, and slide the shaft back in and install the retaining key up front. Align the rockers you can, and install their clips. Then, rotate the engine until you can slide the parked rockers back into place. Be careful you don’t get the parked rockers hung up on one of the lobes. Direction of rotation to unpark can be important.[/quote]
This is good guidance.
My addition to it would be on how to move the reluctant rocker arm shaft. The trick is to bonk on the end of the shaft so you can coax it forward. By using a pair of vise grips and a handy big bolt or a small socket extension, you should be able to position a “drift” on the other side of the rocker arm shaft. Then bonk on it and move the rocker arm shaft forward.
As the shaft moves forward you need a progressively longer drift so add socket extensions. Just be wary of the odd socket extension that is a little beefier than the others because it can hang up on the holes in the AL head. You’ll feel sheepish if you’ve been whacking on your drift for a while before you realize that instead of pushing the rocker arm shaft all you’ve done is bash up the rocker arm shaft’s AL hole.
That joke would have worked better if the head was made of Arsenic.