Can I change the valve springs without pulling the head?

I've heard of pumping the cylinder full of air, but I don't know where to get a "chuck" to put on the compressor hose.

Can I bring each piston to TDC to keep the valves from dropping while I change the springs of that cylinder?

I would save time (and a head gasket) if I can do this.
Thanks

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"Nothing in all creation is hidden from God's sight. Everything is uncovered and laid bare before the eyes of Him to whom we must give account."

My GTO is in the driveway right now with a broken spring removed. A new set will be here tomorrow of a different design.

I have used the air method, but it leaks past the rings and if you want to quit for awhile...well. Also, if something goes wrong and the piston is at BDC your valve could possibly fall in if your seals and guides are worn.

Also, sometimes air pressure isn't enough to keep the vale from popping open instead of releasing the locks from the retainer.

So you need something to fill the combustion chamber so the valve won't open and the locks release.

I used a long piece of cotton rope(clothes line) and ran it thru the spark plug hole. then brought the engine up to tdc with a wrench really tight...then popped my 200# seat pressure springs with ease...use a strong neo or cobalt style magnetic pickup to grab the locks(or needle nose but not as easy).

I've done it this way many times and will be doing all sixteen springs tomorrow.

Gearhead

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64 GTO...10.80's@122 on street radials
Destroked 455, Qjet, stock ign, 2400 stall

64 Valiant
Old 225, 4spd, 2.92-8.75, 2bbl, headers
dual 2.25"

napa or carquest has the adapter to connect to the air hose to hold the valves in place. I read in car magazine that before you apply air the crankshaft has to be held in place to prevent the piston from turning.

Thats true, you can lock the piston near TDC, and it would probably have better ring seal there as well.

But I've still found the rope method to be simple but effective.

Gearhead

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64 GTO...10.80's@122 on street radials
Destroked 455, Qjet, stock ign, 2400 stall

64 Valiant
Old 225, 4spd, 2.92-8.75, 2bbl, headers
dual 2.25"

The rope method it is.
Thank you sir.

_________________
"Nothing in all creation is hidden from God's sight. Everything is uncovered and laid bare before the eyes of Him to whom we must give account."

Snapped a quick pic showing the rope hanging from my spark plug hole and the compressor having squeezed the spring far enough to retrieve the locks.



Later

Got to do the next fifteen...

Karl

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64 GTO...10.80's@122 on street radials
Destroked 455, Qjet, stock ign, 2400 stall

64 Valiant
Old 225, 4spd, 2.92-8.75, 2bbl, headers
dual 2.25"

I have used the rope method on all 12 seals and it works great.

Lou

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Home of Slant6-powered fun machines since 1988

I should also mention that it is a good idea to smack the valve retainer a few good times with a rubber mallet to break the locks grip on the retainer.

After I remove all the rockers, I go around and smack all the retainers a couple times.

Else, I've had problems getting them to release before...maybe no big deal with low spring rates of a slant, but on this roller valve train its needed.

Karl

_________________
64 GTO...10.80's@122 on street radials
Destroked 455, Qjet, stock ign, 2400 stall

64 Valiant
Old 225, 4spd, 2.92-8.75, 2bbl, headers
dual 2.25"

I finished the springs and this method worked great. I saved a lot a of time not taking off the head.

Here's another tip. Put a rag down in the head below the spark plug hole so that you don't drop a keeper down into the motor accidently. If you do, you'll be pulling off the oil pan.

I'm not saying this happen to me ...

_________________
"Nothing in all creation is hidden from God's sight. Everything is uncovered and laid bare before the eyes of Him to whom we must give account."