HELP! Valve seal replacement

[HopLite]

What I've done:
- Remove air cleaner, etc.
- Remove valve cover
- Remove all spark plugs
- #1 cyl @ TDC on compression
- Remove valve support block bolts
- Remove valve rocker arms/rocker arm supports/rocker arm shaft together
- Thread hose into #1 spark plug hole, juice it to 100psi with compressed air
- Attempt to compress spring on front most valve

After compressing the valve spring to the point that I can remove the keepers, I noticed that the valve itself would 'fall' about 3/16". So I did not remove the keepers for fear that the valve would fall into the cylinder.

Questions:
1) I thought the compressed air was supposed to keep the valve up? My compression is good, my 33gal air tank is juiced, I do no hear any 'hiss' of a leak. I do not hear any 'hiss' when the valve 'drops.'
2) If the valve did fall in and I am at TDC, would I still be able to grab the tip top of the valve or would it fall all the way in?

I have adjusted my valve lash many times and did not think it would be a big deal to go a few steps further. I was wrong! This is my daily driver...please respond!!!

Thank you!

 

[Mark W]

here is a simple foolproff alternative...
forget the compressed air... get a piece of clean rope that is mall enough to push through the spark plug hole.... lower the piston away from DTC... feed rope in... raise piston until the rope is jammed up tight in the chamber and the piston won't go any further...

Now the valve can not fall.


Mark...

 

[HopLite]

I nearly bailed to the rope method but then I realized that the stem core was on the hose that I was using to inject the air

The rope method, however, is a golden plan B. Thank you for the reminder!

I have replaced all 12 valve seals and had to quit for the night due to severe thunderstorms and my lack of a garage