ThunderZ28

iTrader: (7)

I have got a valve ( 7th one from the front on the drivers side) that wont slide all the way down, and it sticks once you get it as far down as it will go.
any ideas as to why?
I know I will have to pull the head to repair it, just trying to figure out what I will be getting into when I open this can of worms so that I can have everything ready when I do it.
thanks

1slow01Z71

iTrader: (36)

May be hittin the piston. Why are you shoving the valve all the way down its not necessary to change out valve guide seals?

ThunderZ28

iTrader: (7)

the seals I was doing because I had a leak, but I have had another problem for a while, and was checking the valve stems to see if any where bent..
rotating them, and making sure they slid up and down freely with out any problem..
so far the only one I have problems with is the one stated above..
I think this is why i am having the loud tapping noise sometimes..
doesnt look like it's going to be the lifters after all. but instead it's a
bent valve, bent valve stem, or something in the chamber???
I am leaning to the thought of it being a bent valve stem...
anybody know if you can buy just 1 or do you have to buy the whole set?


and I know it's not hitting the piston.. the chamber was being filled with 110lbs of air.. forcing the piston down.. the exhaust valve would go all the way down.. it's the intake valve that wont go down unless you tap it down.

Rhino79

iTrader: (7)

You should be able to get just one valve.

1slow01Z71

iTrader: (36)

You can get just one valve give Clear Lake Speed a call they can hook you up with a valve.

ThunderZ28

iTrader: (7)

how about the stock size for a 4.8L anybody know that?

ThunderZ28

iTrader: (7)

anyone????

SSlow 4.8

iTrader: (4)

idk if this will help but... all i could find is...

Intake Vavle Seat Width:
.040 to .060 inch.

Intake Vavle stem-to-guide clearance service limit:
.0037 inch.

erronisme

If your vlave is bent then your also going to want to change the valve guide and look at the wear on the valve seat.

I would think that any machine shop should be able to get you a valve and a valve guide. They probably wouldnt charge very much if you brought in the head; and it was clean, to just swap out the one valve. They may even do a valve leak test on the remaining valves.
Depends on the shop I guess.

ThunderZ28

iTrader: (7)

well, got the heads torn off, and it's not a bent valve..
but the valve stem does have some marring on it, that looked to be what was causing the valve to hang up ...
now I am in the process of cleaning everything up, and getting it ready to put back on...
went ahead and put in a new set of lifters as well, as I had a new set of comp lifters witting here anyways...

any suggestions while i have the motor tore down??