Hydraulic lifter retrofit

[mrbell321]

So... what is involved in retrofitting hydraulic lifters to an engine that came with solid lifters? I've seen stuff about going the other way... but I'm not after every last rev or HP(and I'm not a luddite)

[Eddie010]

The only things that you need to change is
the cam
the lifters
and the pushrods.

['77 Westy]

And rocker spacers.
But don’t do it.

[R2.0]

The only things that you need to change is
the cam
the lifters
and the pushrods.

And while I think you can get a new hydro cam, I'm not sure you can get the lifters new. So that means either regrinding a used set of lifters, or getting a used cam and lifters, all matched up lifter-to-lobe.

By the time you do that you'd be better off just getting a hydro core with the lifters still there.

[Clatter]

And rocker spacers.
But don’t do it.

Exactly.
You might also consider running the later hydraulic lifter case with the different oil bypass,
But i’m not sure that’s needed.

Why to hate hydraulics:
1. They bleed down when set on their side for a long time.
Or a short time sometimes.
The clattery pump-up period can be nerve wracking.

2. They’re picky about clean oil - not always a problem but can matter in hard use and long bus journeys.

3. Quality is getting spotty on some lifters

.4 This should be #1.
How are you ever going to know the condition of your valvetrain?
Because the achilles heel of these motors is the valves and seats,
With solids you’re always going to hear trouble or feel it at valve check time.
Otherwise, it might be a catastrophic “too late” scenario when you discover there was a problem.


When you have everything dialed in right,
Most every oil change valve adjustment becomes just a valve check.
Even with a heavy hard-run bus, the valves will not need adjustment for tens of thousands of miles.

[mrbell321]

Yeah, It probably won't happen, at least any time soon. Perhaps if/when I decide to strip the block down and rebuild it. I was just curious if there were casting differences, or insurmountable challenges.