question on how to change springs?
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From: bridgwater, nj
question on how to change springs? I read the LS1howto and it says you can use the compressor to keep the valves up when changing the springs. Do I just hook up my compressor directly to my 10" spark plug adapter hose from my comp. tester (minus the tester of coarse)? I won't have any way to contol the pressure other than the regulator on my compressor, is that alright? Thanks.
Here's what I did 0f course I over do everything. I turned the engine over by hand until the piston was at TDC. I used an ice pick in the spark plug hole to verify the piston was all the way up. Then I hooked up 60 psi using the compressor regulator as well. On the passenger side rear I had to rig up a 90 degree elbow. You have to stick it in gear to keep the motor from rotating if you have all the spark plugs out. I did this as it is possible drop the valve by accident with air but no worries with it at TDC. You will hear air start leaking out if the keepers don't release. I would just tap the top of the valve with a rubber mallet and it would release.
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From: BFE
Originally Posted by GuitsBoy
Can you do the TDC method without pulling the timing cover? Its easy enough to do during a cam swap, but what about when youre just changing springs?
-T
-T
This method requires you to put the piston at the highest position in the bore, so that when you start to compress the spring, the valve can only drop until it hits the piston. When the piston is at top dead center, the valve can't move very far at all.
There are several ways to accomplish this:
A) You can place a small stick/rod/straw/something into the spark plug hole and have a buddy turn the crankshaft by putting the stock 24mm crank pulley bolt in and turning the bolt with a wrench. You should be able to feel when the piston comes up to the top.
B) This method is a bit more elegant. Rotate your motor over by hand until your cam gear and crank gear are dot to dot like you set them up as earlier. At this position, piston 1 and 6 should be at top dead center. You can change the 4 springs on these 2 cylinders now using the instructions below. After you change those 4, then, rotate the crankshaft a full 90 degrees, and the cam gear dot will turn 45 degrees, as if it is pointing to 7:30 if it were a clock. Now piston 8 and 5 are at the top and can be changed. Rotate another 90 degrees on the crank and your cam gear dot will now be at 9 o'clock. Piston 7 and 4 can now have their springs changed. And FINALLY, rotate the crank another 90 degrees and the cam gear dot will be at 10:30. You can now change your remaining four springs on piston 3 and 2.
Once again, that's 1 & 6, rotate 90, 8 & 5, rotate 90, 7 & 4, rotate 90, 3 & 2.
BY JMX
I second the TDC method. I just got done with my cam and spring swap and thats what I did. The compressed air method just looked like a pain in the *** to me. Plus I needed the air compressor for my air ratchet to compress the valve spring, using the Larry tool, anyways.
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From: bridgwater, nj
Thanks guys, TDC method seemed easier but the compressor way sounded more professional. I will try TDC. I was just afraid of dropping a valve. I just bought my new air compressor. Should have posted first. 
Oh well, it will not go to waste.
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Verdad Gallardo Can the crank be scribed or otherwise marked somewhere visable from outside so its easy to line it up again next time I swap springs? I dont know if any part of the crank is visable with the pulley still on, and since the pulley is not a splined fit, i dont feel safe marking the pulley.
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From: bridgwater, nj
Originally Posted by tomaSS
I second the TDC method. I just got done with my cam and spring swap and thats what I did. The compressed air method just looked like a pain in the *** to me. Plus I needed the air compressor for my air ratchet to compress the valve spring, using the Larry tool, anyways.
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From: BFE
just use a regular ratchet. 
why not use an impact while you are at it?
(sorry couldn't help it)
Please read this
http://ls1howto.com/
why not use an impact while you are at it?
(sorry couldn't help it)
Please read this
http://ls1howto.com/
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From: Raleigh, NC
My vote is for the air method. Just DO NOT hook unregulated shop air into the cylinder!! I made the mistake and the car started to move forward in gear. I unhooked the air hose in a hurry, and got a regulator.
Originally Posted by BLASTER
I was plannig on just tightening the Larry tool down by hand. SHould I use the air rachet too? Didn't want to strip anything.
Good luck. Thread Starter
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From: bridgwater, nj
Originally Posted by PREDATOR-Z
just use a regular ratchet.
why not use an impact while you are at it?
(sorry couldn't help it)
Please read this
http://ls1howto.com/
why not use an impact while you are at it?
(sorry couldn't help it)
Please read this
http://ls1howto.com/
I would not recommend doing it by hand. It will take so long. The air ratchet won't have enough torque to break the stud if you don't go all the way down (which you won't have to). Use a deep socket and you wont strip the nut. Just have a magnet ready for the locks so they don't go flying off. I did not have a problem at all. I could not imagine tightening the nut down by hand. That would be Good luck.
Used a compressor on a car some years back and the piston moved to the bottom. Of course, you know what happened next, lost air pressure and found a nice round hole where the valve used to be Ever since then, I have used a small thin soft nylon rope in the spark plug hole and put the piston up to compress the rope (not tight). The "TDC" mentioned above is probably the safest method, but I would verify the piston position with a chopstick or something because I have a tendency to miscount or do some other stupid screwup. 
Ever since then, I have used a small thin soft nylon rope in the spark plug hole and put the piston up to compress the rope (not tight). The "TDC" mentioned above is probably the safest method, but I would verify the piston position with a chopstick or something because I have a tendency to miscount or do some other stupid screwup. 
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From: Northern Va
Originally Posted by vettenuts
...I have used a small thin soft nylon rope in the spark plug hole and put the piston up to compress the rope (not tight)...
Will it?