5.3litre

iTrader: (6)

I'm helping a bud change out a cam on his car. As soon as we took the timing cover off. We put the old crank bolt back in and tried to turn the engine with a rachet and the 24mm socket that goes over the crank bolt. We just wanted to see if we could get a look at the dot on the crank gear, but the engine is really tough to turn and we didn't wanna damage the crank snout with the bolt. Is this normal? Do we need to remove the spark plugs? When we were tryin to turn it, we could hear some wierd compression noises so we stopped. Like i said, we were just tryin to locate the dot on the crank gear. thanks

elgp

remove a spark plug or two its the compression and that noise you guys herd is probably the compression trying to get out good luck on the cam swap

67rsss

iTrader: (4)

These engines run pretty tight compression. Pull the plugs.

5.3litre

iTrader: (6)

ok cool. We will pull the plugs. thanks guys

elgp

take one off from each side

vettenuts

iTrader: (4)

Pull all the plugs. Then remove the valve train. If you don't it will be hard to line up as the valve springs will move things.

67rsss

iTrader: (4)

That doesn't make sense. Pull all the plugs, you are moving the pistons and trying compressing any air in the cylinders. Since the rockers are loose, the valves won't open, and the air can't get out. Pull the plugs and you de-compress all the chanbers and the engine spins much easier.

TooLateVTEC

iTrader: (2)

Take them all out and it will be much easier.

The compression of the motor is keeping you guys from turning it over, and yes its completely normal.

Good luck on your cam swap.

5.3litre

iTrader: (6)

Well we were hoping to not touch the valvetrain. Just recently he had a shop install a small cam and some comp 918's and hardened pushrods. Then he decided after about 500 miles that he wants a bigger cam So we don't need to change the springs. Is it a must to remove the springs to get everything to line up?

S10xGN

iTrader: (11)

Not if you're just changing the cam, but you'll still need to remove the rockers and pushrods (I'd make sure they go back in the same place they came from). PLEASE don't forget to retain the lifters, either by 5/16" dowel rods or pen magnets.

Russ

67rsss

iTrader: (4)

You are not going to change the cam without messin' with the valvetrain. Keep them in order, but the rockers and pushrods need to get out of the way. Valves springs should be fine. You need to shoot the lifters into the retainers, and then run a dowel or rod down the gallery to make certain they don't fall. If a lifter falls, life gets a little harder.

5.3litre

iTrader: (6)

Damn we were hoping to leave the valvetrain in tact. Oh well. And yea i know about the lifters. We have read through the ls1howto write up.

SS#1230

nah dude, you cant just pull the cam out. you would get it out a little bit then once you slid the cam out from under the lifters, they would hang up on the lobes, then youd be up poo creek! and if somehow you got it out, the springs would push the rockers which would push the rods, which would push your lifters and drop them down into the bottom end, then your pulling the motor and fishing out the lifter/lifters through the pan...

you have to pull the rockers off, get the lifters up off the lobes and then pull it out. and a very good idea to hold the lifters up and pull the PRs out too....

not a big deal to pull the rockers and the pushrods....


oh, i know its obvious, but i didnt see it mentioned......take it outta gear when trying to turn the motor over with the crank pulley bolt

BAMF

Is it common for the lifters to fall back down as the cam is being taken out? and where are you sticking this rod in to hold the lifters up?

67rsss

iTrader: (4)

Once you have the retainer plate off, you will see the two galleries.

SS#1230

this will answer your questions...

http://ls1howto.com/index.php?article=23