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-   -   How do I adjust my valves??! (https://67-72chevytrucks.com/vboard/showthread.php?t=525629)

blazerboy_4life 05-20-2012 09:29 PM

How do I adjust my valves??!
 
I have a 350 that now has about 400 miles on it and my valves are makin noise. I have a basic working understanding of how an engine works but Im not fluent in the terminology or the technical stuff. That being said can anybody tell me what I need to do to make my first adjustment? Im very mechanically inclined so if its just explained to me I dont think Ill have any problems. Thanks in advance everyone.

Rob

by the way I have a bigger cam 447/447 i think, and roller rockers.

Shane22696 05-20-2012 09:36 PM

Re: How do I adjust my valves??!
 
You have to take the valve covers off, and you loosen or tighten the nuts on top of the rocker arms. If you're adjusting them cold, tighten them until you can't move the pushrods up and down by hand at all, and then tighten the nut another 1/2 turn

blazerboy_4life 05-20-2012 10:07 PM

Re: How do I adjust my valves??!
 
So its just that simple huh? Make sure everything is snug but not over tightened? Without adjusting anything i cannot move the pushrods at all now but i can wiggle about 6 out of 8 of the rockers. Is that right? Or do i just snug those up a little?
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cableguy0 05-20-2012 10:14 PM

Re: How do I adjust my valves??!
 
Slow down. Theres a bit more to the process than just tightening the nuts down. You need to ensure the lifter is on the back side of the cam lobe. The adjustment method you need to use is known as Exhaust open/intake closed method. Your going to have to rotate the engine. Pick a cylinder to start with and watch for the exhaust pushrod to start moving up. At that point adjust the intake valve on that cylinder. Now spin the engine until you see the intake valve open up and go almost all way the closed now you can adjust the exhaust on that cylinder. Work your way through the firing order and it wont take near as long as it sounds like it should. Also just to save some time did you break the cam in properly? Are you using a zinc additive? If you answer no to those question more than likely your new cam is already wiped out.

blazerboy_4life 05-20-2012 10:56 PM

Re: How do I adjust my valves??!
 
ok. Thanks. Ill give it a try. Now if I mess this up and over/under do something whats the worst case scenario? Can I ruin valves, the head or otherwise? This is one of the steps of building an engine I've never been through.

Shane22696 05-20-2012 11:25 PM

Re: How do I adjust my valves??!
 
Crap, completely skipped the step about making sure the lifters are off the lobes. But yeah, just work your way through the firing order. You shouldn't screw it up too bad, it's not real hard once you get going. But as with anything else, if something looks or feels too far off stop and ask for help.

blazerboy_4life 05-21-2012 01:41 AM

Re: How do I adjust my valves??!
 
Well its getting windy here and I cant work on the truck in the garage right now so Im gonna call it a night on this project. Hopefully Ill pick back up tomorrow after work and I can get this done.

truckdude239 05-21-2012 08:25 AM

Re: How do I adjust my valves??!
 
I always get mine close by feel then fire it up and do one side at a time back it off till it MAKES noise and tighten up till its gone then 3/4 a turn more and never had a problem like that btw this can get very messy

butch86 05-21-2012 09:31 AM

Re: How do I adjust my valves??!
 
i cut the top out of an old valve cover to keep the oil from flowing outside the head. the center bolt valvecovers i took a peice of 3/4 wide flat stock and drilled a hole in it and clamp the vc down in 2 placeses. there ugly but work well for running valves on a running motor.

Marv D 05-21-2012 10:20 AM

Re: How do I adjust my valves??!
 
If your loosing preload on the lifters,, something is going away. Hopefully you had a successfull breakin.
Here's the non messy way to set preload on hydraulics

storm9c1 05-21-2012 10:52 AM

Re: How do I adjust my valves??!
 
TIP:
Loosen up (or pull out completely) all the spark plugs. Makes the engine rotate MUCH easier while going through this process because you aren't fighting compression.

blazerboy_4life 05-21-2012 03:35 PM

Re: How do I adjust my valves??!
 
Quote:

Originally Posted by Marv D (Post 5392230)
If your loosing preload on the lifters,, something is going away. Hopefully you had a successfull breakin.
Here's the non messy way to set preload on hydraulics

Can you explain more about the pre load? How would the break in not be successful in my situation?

Marv D 05-21-2012 04:01 PM

Re: How do I adjust my valves??!
 
PRELOAD is what you set in hydraulic lifers, LASH (meaning a 'gap) is for solids. The sbc hydraulic lifter has roughly 0.065" to 0.080" range in the hydraulics. Johnson controls that made most of the stock type lifters said 'ideal' is 0.030" into the hydraulics. Places you roughly right in the middle of the hydraulic travel.

Breakin failure..... Todays oils do not support flat tappet cams worth a CRAP. If you have high load springs, and todays crap oil, and were lucky the 20 minute / 2500-3000rpm breakin proceedure worked. The high RPM's is all about oil sling off the rotating assembly to bathe the cam in oil to cool it while the new cam lobe and new lifter grind away at each other to find a happy medium they both can live with . The drainback from the heads is not enough to cool the hardened surface so,,, spin it up to sling oil off the crank / rods to bathe and cool the cam. Even then, with the oil not formulated to support the high firction / high pressure point of a flat tappet cam,,, failures are about 20%

Hope your not one of the unlucky ones.The first hit a lobe failed is a 'ticking' from the valve train. Not saying you absolutely have that issue, just that if you DO, your circulating debris through the entire engine every time you run it. I'd investigate WHY the rockers got loose before just adjusting and forgetting them until the tick returns.

but just my 2¢

shawno72 05-21-2012 04:08 PM

Re: How do I adjust my valves??!
 
Good tips, thanks guys.

blazerboy_4life 05-21-2012 10:09 PM

Re: How do I adjust my valves??!
 
Ok I currently have my covers off, all plugs pulled and Im sitting at TDC. Now Ive made several rotations now and the most play I end up with is a little wiggle in a rocker. The rods are never able to move up and down at all. They only spin and rockers wiggle. Does this sound right for an engine with about 400 miles on it? Where do I go from here?

blazerboy_4life 05-21-2012 10:11 PM

Re: How do I adjust my valves??!
 
Should I back them off and reset them all?

blazerboy_4life 05-22-2012 08:35 PM

Re: How do I adjust my valves??!
 
Anybody??

shawno72 05-22-2012 08:42 PM

Re: How do I adjust my valves??!
 
Wish I knew. I will learn from this as well. Bump for ya
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blazerboy_4life 05-22-2012 10:41 PM

Re: How do I adjust my valves??!
 
Glad Im not the only one who will be getting something out of this!

Marv D 05-22-2012 11:42 PM

Re: How do I adjust my valves??!
 
Yeah,, that stinking work thing keeps answers slow to come don't it

Not sure what your describing. If the rockers never get 'loose' on the valve stem,, you probably just have no big problem. Is this a Comp XE cam,, if so get used to the valvetrain noise. It's a common thing in the XE series.
Ideally if you want to REALLY check,, you would set up a dial indicator on each and every valve spring retainer and measure the lift. If it's ALL equal (intakes equal and exhausts equal) then resetting the preload is the next step.

But ... sometimes stock rockers and poor valvetrain geometry is just noisy. The old 'turn up the radio' solution comes to mind.

71 GMCDRVR 05-23-2012 04:46 PM

Re: How do I adjust my valves??!
 
The best way is the EO IC method. shoot me your email in a pm and ill send it to you (can't upload for some reason) If the engine is already in the truck I do it while running (I know some guy's don't like this method, but I have never had an issue with it) and to answer the question of what could happen you can end up roachn your cam and sending all that metal through the motor and subsequently ruining it. So yes proper valve adjustment is a huge deal!!

71 GMCDRVR 05-24-2012 01:15 AM

Re: How do I adjust my valves??!
 
Quote:

Originally Posted by truckdude239 (Post 5392083)
I always get mine close by feel then fire it up and do one side at a time back it off till it MAKES noise and tighten up till its gone then 3/4 a turn more and never had a problem like that btw this can get very messy

Same here!!!!


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