How do I adjust my valves??! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

blazerboy_4life · 05-20-2012, 09:29 PM

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

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

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

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

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

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

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

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

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

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

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

Quote:

Originally Posted by Marv D

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

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

Good tips, thanks guys.

blazerboy_4life · 05-21-2012, 10:09 PM

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

Should I back them off and reset them all?

blazerboy_4life · 05-22-2012, 08:35 PM

Anybody??

shawno72 · 05-22-2012, 08:42 PM

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

Glad Im not the only one who will be getting something out of this!

Marv D · 05-22-2012, 11:42 PM

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

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

Quote:

Originally Posted by truckdude239

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!!!!

05-20-2012, 09:29 PM	#1
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	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.

05-20-2012, 09:36 PM	#2
Shane22696 Registered User Join Date: Jul 2011 Location: Zebulon GA Posts: 128	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 __________________ 80 K10 350 4 spd 4 Inch lift, 33 inch BFG M/t

05-20-2012, 10:07 PM	#3
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	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? Posted via Mobile Device

05-20-2012, 10:14 PM	#4
cableguy0 Senior Member Join Date: Apr 2000 Location: Delta,Pa Posts: 14,948	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. __________________ Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.

05-20-2012, 10:56 PM	#5
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	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.

05-20-2012, 11:25 PM	#6
Shane22696 Registered User Join Date: Jul 2011 Location: Zebulon GA Posts: 128	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. __________________ 80 K10 350 4 spd 4 Inch lift, 33 inch BFG M/t

05-21-2012, 01:41 AM	#7
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	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.

05-21-2012, 08:25 AM	#8
truckdude239 Senior Member Join Date: Sep 2005 Location: Lewisville, Nc Posts: 10,237	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 __________________ David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube

05-21-2012, 09:31 AM	#9
butch86 Registered User Join Date: Mar 2012 Location: harrisville, ms Posts: 377	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. __________________ most people sleep peacfully at night because, rough men stand ready to do violenceon there behalf.

05-21-2012, 10:20 AM	#10
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	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 __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.

05-21-2012, 10:52 AM	#11
storm9c1 * That's interesting * Join Date: Oct 2008 Location: Pittsburgh, PA Posts: 2,772	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. __________________ Tom Chevy by day... 1969 Chevy C30 Rollback Tow Truck -- 383 stroker, 4L80E 2011 Chevy Caprice PPV 9C3 6.0L 1995 Chevy Caprice 9C1 1994 Chevy Caprice 9C1 #3 1995 Chevy Caprice Wagon #2 1995 Chevy Impala SS Mopar by night... 1969 Dodge Charger 1972 Chrysler Newport 2dr Hardtop (27K miles) Plus others...

05-21-2012, 04:01 PM	#13
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	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¢ __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.

05-21-2012, 04:08 PM	#14
shawno72 C/10 junkie Join Date: Nov 2010 Location: Stockton Ca Posts: 9,093	Re: How do I adjust my valves??! Good tips, thanks guys. __________________ Shawn 70 LWB C10 current driver/project http://67-72chevytrucks.com/vboard/s...d.php?t=663051 68 SWB C10 Work in progress.....SOLD http://67-72chevytrucks.com/vboard/s...d.php?t=559520 72 LWB C10 Sold 71 LWB C10 Sold 68 LWB C10 CST Sold http://youtu.be/kbB0QrBIs9k My mom always had the best advice. It was just a tad late. After a fall that involved blood, she'd say....."Careful!"

05-21-2012, 10:09 PM	#15
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	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?

05-21-2012, 10:11 PM	#16
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	Re: How do I adjust my valves??! Should I back them off and reset them all?



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05-22-2012, 08:35 PM	#17
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	Re: How do I adjust my valves??! Anybody??

05-22-2012, 08:42 PM	#18
shawno72 C/10 junkie Join Date: Nov 2010 Location: Stockton Ca Posts: 9,093	Re: How do I adjust my valves??! Wish I knew. I will learn from this as well. Bump for ya Posted via Mobile Device __________________ Shawn 70 LWB C10 current driver/project http://67-72chevytrucks.com/vboard/s...d.php?t=663051 68 SWB C10 Work in progress.....SOLD http://67-72chevytrucks.com/vboard/s...d.php?t=559520 72 LWB C10 Sold 71 LWB C10 Sold 68 LWB C10 CST Sold http://youtu.be/kbB0QrBIs9k My mom always had the best advice. It was just a tad late. After a fall that involved blood, she'd say....."Careful!"

05-22-2012, 10:41 PM	#19
blazerboy_4life 70Custom10 Join Date: Jan 2010 Location: Rapid City, SD Posts: 322	Re: How do I adjust my valves??! Glad Im not the only one who will be getting something out of this!

05-22-2012, 11:42 PM	#20
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	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. __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.

05-23-2012, 04:46 PM	#21
71 GMCDRVR Registered User Join Date: Aug 2011 Location: Modesto, Claifornia Posts: 236	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!! __________________ Blessings, Ryan G JESUS IS LORD!!!!!!

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