Do I need an air comp. to change out valvesprings

[NorCal66]

Alright, I know I've been talking about it for about the last year, but I'm finally ready to change my valve springs out, I've got em bought and sittin at my feet. IM REALLY GOING TO DO IT THIS TIME. Thing is, my shop manual says to screw in an air hose into the the CC through the spark plug hole and use compressed air to get the valves up. Problem...no air compressor. Has anyone ever changed out their springs, with heads still on the car any other way? If not, what would I call the adapter that screws into the spark plug threads?
I have 0 money to pay to have this done, I'm a month away from leaving for school and am already a broke college student.

Thanks for the help guys.

errr...one more thing...with these springs (edelbrock Performer RPM springs) would I be saving myself a future headache by putting in hardened pushrods?

 

[6Stang7]

I am pretty sure that you can hand crank the engine over till the cylinder you are doing is at TDC to prevent the valves from falling all the way down. Not 100% sure that this works though, but it should.

 

[my66coupe]

Yes you need the air compressor. When I was changing messing around with different valve spring set ups, I needed it. Even if you set the piston to TDC, the air from the compressor will force it down... Go rent one, your also going to need the fitting for the spark plug port and a spring compressor. I removed the keepers/retainers, with a magnet. Good luck

Mike

 

[D.Hearne]

If you don't have the cash to do the job , then don't do it. I take it your present valve springs are performing OK? If they are then leave them be. Do the swap when you can afford it.

 

[ashford]

use the hose off of a compression tester when the time comes

 

[2nd Mustang]

......or the rope-a-dope method...no just kidding, but really, I picked up this idea from SD and others on this forum. Use household rope, and install into spark plug hole then turn the crank by hand until the rope is compressed enough at TDC to prevent the valves from dropping into the cylinders when you remove the springs. I've never tried this method, but it seems like it should work.

 

[damannhw]

Here's another tip that will help if those springs have been there awhile ! You will need a 9/16 deep socket and rubber mallet. Place the socket (big end) over the valve tip on top of the valve spring keeper and give it a couple of taps with the mallet. Those keepers always stick in place if you don't !!!

 

[Max Power]

The rope method can work, I've used it. I am also wondering about the need for new springs since your budget is so tight. Doesn't sound like you have any room for error, and that is a bad place to be with vintage cars.

 

[NorCal66]

True, on the budget thing, I meant more in the sense as I didn't have money to have my mechanic do them, which I'm sure would be another $200 as everything always takes more time than suspected. I have plenty to rent a compressor for a day or two if it's really necessary. I'm wanting to change them out because it's increasing getting louder under the hood, which may just be some loose rocker arms, but the idea of one of those puppies breaking doesn't sound good. Anyways, thanks a lot for the info guys!

Yea stock springs on a .520 cam.

Ugh...I hate to ask this but how do I manually crank the engine? Spin the crank pulley?

 

[6Stang7]

Yes you need the air compressor. When I was changing messing around with different valve spring set ups, I needed it. Even if you set the piston to TDC, the air from the compressor will force it down... Go rent one, your also going to need the fitting for the spark plug port and a spring compressor. I removed the keepers/retainers, with a magnet. Good luck

Mike

No no, what I ment by my suggestion was that he doesn't you compress air at all when doing this (since he can't get ahold of it). What I am thinking here is that when the piston is at TDC for that cylinder, it piston itself will prevent the valve from falling all the way into the cylinder. I think that the valve drop down, but there will still be enough of the stem for you to be able to lift it back up.

 

[my66coupe]

I see what you mean, but I bet the valve would still drop a bit, enough for you to grab. Just imagine what a PIA it would be to have to hold the valve up and install the Spring all at once. The compressor keeps the valve up for you.... Try the rope idea it sounds like it would work, just make sure you get a lot in there, so you can pull it back out Ya remove your fan, and shroud if you have a large one, get a socket on the crack bolt/key and start spinning.

Mike

 

[Max Power]

Do you have screw in studs? Because if you have a .520 lift cam with RPM springs and press-in studs, you will probably have problems with studs pulling out. You may have that problem already.

Increasing noise in the valvetrain is rarely a spring failure problem.

 

[ratio411]

Use the rope.

I agree that press in studs with new performance springs are not the best idea. You may be okay, but then, you may pull a stud right out. Those springs are probably borderline too much.
Good luck
Dave

 

[5.0n66]

not much air flows by the valves when using the air compressor method..... what about using a foot powered bike pump? (with some creative plumbing) wouldnt flow much air but seems like it would be plenty to keep valve in position (make sure you keep it pressurized though)

 

[NorCal66]

Hmm all good ideas...I found an air compressor one of my dad's friends owns, so that is no longer an issue. I tried searching around with no avail, maybe someone can educate me...the block is a 68 and I'm fairly sure the heads are as well. Are 68s push or screw in, or does it depend on the engine code?

 

[D.Hearne]

There's a 90 % chance the heads you have, have pressed in studs. The ONLY factory heads ( small block ) that had screw in studs were the Boss 302 and the 289 Hi-po's. Of course your heads are 30 something years old, and someone could have had them machined for screw in studs ( if you're lucky)

 

[Max Power]

Yup, I'm guessing press in. If it were my car, I wouldn't put those springs in with press in studs.