valve adjustment - The 1947 - Present Chevrolet & GMC Truck Message Board Network

fdbdw · 01-30-2009, 12:49 PM

350 sb valve adjustment, everyone has a dfferent opinion Ive been told 1/4, 1/2 turn 3/4 and full turn after zero lash any one know for sure or is there away to tell whats best for yours,

BluTrukker · 01-30-2009, 01:13 PM

My manual says 3/4, but I have found that is too much in some situations. I go with 1/2 and snug up if they make noise when its running

68gmsee · 01-30-2009, 01:42 PM

Quote:

Originally Posted by fdbdw

350 sb valve adjustment, everyone has a dfferent opinion Ive been told 1/4, 1/2 turn 3/4 and full turn after zero lash any one know for sure or is there away to tell whats best for yours,

The reason you have so many opinions is that no two engines are going to have the same type of wear or identical parts. Some require tighter adjustment than others.

You have a standard that the books call out for most vehicles. I adjust mine like BluTrukker mentioned when I install new lifters: remove all lash and turn an additional 1/2 turn. It may vary plus or minus a little.

tim21391 · 01-30-2009, 02:13 PM

mine is set at 0 plus a half.. but mine is a 402..thought id throw that out there

Wreckless_71 · 01-30-2009, 02:32 PM

I believe if you're building a new engine with tight parts it's gonna be zero lash+1/2 turn. On my old warn out 350 in the 2wd I ended up with zero+3/4 turn. Like these guys said before me it all depends on the engine and who you talk to....

joemacho · 01-30-2009, 02:47 PM

yeah i was told also 3/4 turn is good enough on a 350.

drewdude92 · 01-30-2009, 02:49 PM

alright noobie here whats 0 lash?

BluTrukker · 01-30-2009, 02:55 PM

Zero clearance between pushrod and rocker. I spin the pushrod between my fingers as I tighten the rocker down. When you feel some drag and it doesn't spin quite so freely, then you tighten 1/2 turn from there. I'm sure there is a tool for it, but everyone I know goes by feel.

see ten · 01-30-2009, 03:01 PM

I've got manuals that call for a half a turn and I've got em that call for a full turn...So I split the difference at 3/4 of a turn. It's been working out for us so far.

sflanagan · 01-30-2009, 03:28 PM

That usually works however for performance applications the valves call for less of a turn due to the high rpm's you run, let's say 1/4 inch turn for constantly high rpm running engines. If your engine is running a stock combo or mild upgrade 1/2 to 3/4 turn will do you just fine....Sounds like you got it though, just food for thought...

cparman · 01-30-2009, 07:03 PM

I have used this many times, and it is a no mess way to adjust the valves on your small block Chevy. Read the procedure, and what you are looking for is to be able to turn the push rod with a little resistance.

STATIC ADJUSTMENT

1. says to run the engine. On a new engine I always soak the lifters in oil over night. Then do this
2. With engine in position to fire No. 1 cylinder, adjust the following valves: V6-229 and 262, Exhaust Nos. 1, 5 and 6; Intake Nos. 1, 2 and 3. 6-250 and 292, Exhaust Nos. 1, 3 and 5; Intake Nos. 1, 2 and 4. V8 engines, Exhaust Nos. 1, 3, 4 and 8; Intake Nos. 1, 2, 5 and 7. To properly adjust valves, tighten adjusting nut until all lash is eliminated, then tighten nut the specified additional number of turns. On V8-454 / 7.4L engine, tighten nut 3/4 additional turn from zero lash. On all others, tighten nut one full turn from zero lash.
3. Turn crankshaft one complete revolution, which will bring engine in position to fire cylinders 4(V6) or 6(Inline 6 and V8). With engine in this position, adjust the following valves: V6-229 and 262, Exhaust Nos. 2, 3 and 4; Intake Nos. 4, 5 and 6. 6-250 and 292, Exhaust Nos. 2, 4 and 6; Intake Nos. 3, 5 and 6. V8 engines, Exhaust Nos. 2, 5, 6 and 7; Intake Nos. 3, 4, 6 and 8. When zero lash is obtained, tighten adjusting nuts as specified in step 2.

tim21391 · 01-30-2009, 08:24 PM

on my dads mustang all i did was tighten it down snug and it ran perfect..its a 67 mustang with a worn out 79 cougar motor

crm318 · 01-30-2009, 08:46 PM

I think that ford has non-adjustable valvetrain.

dhaymaker · 01-30-2009, 08:57 PM

There are a number of theories on this and, as many responses have indicated, even the books don't all agree. But one issue, as sflanagan indicated, what your engine is designed to do has a lot to do with the lash. If the engine is designed with higher rpm/horsepower in mind, you want the lash a little "looser". If the engine is designed for lower rpm/torque applications, you want the lash a little "tighter". As mentioned in various responses, a big factor is new parts versus old, etc. Personally, unless it's a well-worn engine, I'm a 1/2 lash kinda guy!

100%Chevy · 01-30-2009, 09:28 PM

I use the book "How To Rebuild Your Small Block Chevy"
Probably the most used book on the market.Although a little dated now,it's still the single best source of information on small block Chevies.
It calls for 3/4 turn after slight resistance.This is a starting point for me.After starting and warming the engine,I will loosen each(keeping up with the amount I turn the nut)until I hear noise,then re-tighten it till the noise stops.Sometimes it's more,some less.I do this several times on all of them.
On new engines,you may have to do it again later.On worn engines,some lifters may be too weak to ever be quiet!New parts time!
Mike.

01-30-2009, 12:49 PM	#1
fdbdw Registered User Join Date: Jan 2009 Location: colorado springs Posts: 479	valve adjustment 350 sb valve adjustment, everyone has a dfferent opinion Ive been told 1/4, 1/2 turn 3/4 and full turn after zero lash any one know for sure or is there away to tell whats best for yours,

01-30-2009, 01:13 PM	#2
BluTrukker BOHICA Join Date: Mar 2008 Location: Stewartville, MN Posts: 440	Re: valve adjustment My manual says 3/4, but I have found that is too much in some situations. I go with 1/2 and snug up if they make noise when its running __________________ Trying to save someone from their own stupidity is like teaching a pig to dance. It is a waste of your time, and it annoys the pig!

01-30-2009, 02:13 PM	#4
tim21391 Registered User Join Date: Jul 2007 Location: Salina, Kansas Posts: 1,998	Re: valve adjustment mine is set at 0 plus a half.. but mine is a 402..thought id throw that out there __________________ 1972 C-10...402/400..flowmaster 40 series 1967 Mustang 347 stroker/C-4 1966 Mustang 289/3-speed 2013 Mustang V6/6speed w/300 ponies I may be 23, but i sure do knows 67-72s are sexy! Its not MPG its smiles per gallon! build started 11/25/08 build thread: http://67-72chevytrucks.com/vboard/s....php?p=2993796

01-30-2009, 02:32 PM	#5
Wreckless_71 Registered User Join Date: Apr 2007 Location: Kelso, WA Posts: 363	Re: valve adjustment I believe if you're building a new engine with tight parts it's gonna be zero lash+1/2 turn. On my old warn out 350 in the 2wd I ended up with zero+3/4 turn. Like these guys said before me it all depends on the engine and who you talk to.... __________________ 1972 K10 4" lift, 35’s, 383 stroker, 700r4, current project. 1971 C10 3"/5" static drop, 355/350. "La Bamba.” The current daily driver.

01-30-2009, 02:47 PM	#6
joemacho Registered User Join Date: Aug 2007 Location: peoria az Posts: 252	Re: valve adjustment yeah i was told also 3/4 turn is good enough on a 350.

01-30-2009, 02:49 PM	#7
drewdude92 72 chevys 4 life Join Date: Aug 2008 Location: Crescent,Ok Posts: 406	Re: valve adjustment alright noobie here whats 0 lash? __________________ I dont call it being young and dumb....I call it young and havin fun

01-30-2009, 02:55 PM	#8
BluTrukker BOHICA Join Date: Mar 2008 Location: Stewartville, MN Posts: 440	Re: valve adjustment Zero clearance between pushrod and rocker. I spin the pushrod between my fingers as I tighten the rocker down. When you feel some drag and it doesn't spin quite so freely, then you tighten 1/2 turn from there. I'm sure there is a tool for it, but everyone I know goes by feel. __________________ Trying to save someone from their own stupidity is like teaching a pig to dance. It is a waste of your time, and it annoys the pig!

01-30-2009, 03:01 PM	#9
see ten WTB this ad Join Date: Sep 2004 Location: Lafayette Georgia Posts: 5,073	Re: valve adjustment I've got manuals that call for a half a turn and I've got em that call for a full turn...So I split the difference at 3/4 of a turn. It's been working out for us so far.

01-30-2009, 03:28 PM	#10
sflanagan Registered User Join Date: Jan 2009 Location: Bakerfield, CA Posts: 31	Re: valve adjustment That usually works however for performance applications the valves call for less of a turn due to the high rpm's you run, let's say 1/4 inch turn for constantly high rpm running engines. If your engine is running a stock combo or mild upgrade 1/2 to 3/4 turn will do you just fine....Sounds like you got it though, just food for thought... __________________ -Sean- 68 Chevy fleetside/shortbed, 350 eng., alum. heads, 10 to 1, 430 hp.

01-30-2009, 07:03 PM	#11
cparman sharp as a marble Join Date: Jan 2007 Location: atlantic beach,florida Posts: 1,082	Re: valve adjustment I have used this many times, and it is a no mess way to adjust the valves on your small block Chevy. Read the procedure, and what you are looking for is to be able to turn the push rod with a little resistance. STATIC ADJUSTMENT 1. says to run the engine. On a new engine I always soak the lifters in oil over night. Then do this 2. With engine in position to fire No. 1 cylinder, adjust the following valves: V6-229 and 262, Exhaust Nos. 1, 5 and 6; Intake Nos. 1, 2 and 3. 6-250 and 292, Exhaust Nos. 1, 3 and 5; Intake Nos. 1, 2 and 4. V8 engines, Exhaust Nos. 1, 3, 4 and 8; Intake Nos. 1, 2, 5 and 7. To properly adjust valves, tighten adjusting nut until all lash is eliminated, then tighten nut the specified additional number of turns. On V8-454 / 7.4L engine, tighten nut 3/4 additional turn from zero lash. On all others, tighten nut one full turn from zero lash. 3. Turn crankshaft one complete revolution, which will bring engine in position to fire cylinders 4(V6) or 6(Inline 6 and V8). With engine in this position, adjust the following valves: V6-229 and 262, Exhaust Nos. 2, 3 and 4; Intake Nos. 4, 5 and 6. 6-250 and 292, Exhaust Nos. 2, 4 and 6; Intake Nos. 3, 5 and 6. V8 engines, Exhaust Nos. 2, 5, 6 and 7; Intake Nos. 3, 4, 6 and 8. When zero lash is obtained, tighten adjusting nuts as specified in step 2.

01-30-2009, 08:24 PM	#12
tim21391 Registered User Join Date: Jul 2007 Location: Salina, Kansas Posts: 1,998	Re: valve adjustment on my dads mustang all i did was tighten it down snug and it ran perfect..its a 67 mustang with a worn out 79 cougar motor __________________ 1972 C-10...402/400..flowmaster 40 series 1967 Mustang 347 stroker/C-4 1966 Mustang 289/3-speed 2013 Mustang V6/6speed w/300 ponies I may be 23, but i sure do knows 67-72s are sexy! Its not MPG its smiles per gallon! build started 11/25/08 build thread: http://67-72chevytrucks.com/vboard/s....php?p=2993796

01-30-2009, 08:46 PM	#13
crm318 Alright Alright Alright Join Date: Mar 2004 Location: Midland, Texas Posts: 1,672	Re: valve adjustment I think that ford has non-adjustable valvetrain. __________________ 1972 Cheyenne Chevrolet red and white 357ci, Vortec heads, GM Performance high rise intake, Comp 268H .454/.454 218/218 110 LSA Quadrajet carb, Flowtech headers, 2.25 40 series HEI, Curve kit, TH 350, 3.07 gears 275/60/15s on 15x8 rallies

01-30-2009, 08:57 PM	#14
dhaymaker Registered User Join Date: Jan 2006 Location: Peyton, CO Posts: 448	Re: valve adjustment There are a number of theories on this and, as many responses have indicated, even the books don't all agree. But one issue, as sflanagan indicated, what your engine is designed to do has a lot to do with the lash. If the engine is designed with higher rpm/horsepower in mind, you want the lash a little "looser". If the engine is designed for lower rpm/torque applications, you want the lash a little "tighter". As mentioned in various responses, a big factor is new parts versus old, etc. Personally, unless it's a well-worn engine, I'm a 1/2 lash kinda guy! __________________ don "The DRBMan" 2014 Audi A4 (The Wife's Daily Driver) 2017 HD Ultra (The Cruiser) 2003 HD Fatboy (The Ride) 2001 Chevy Suburban (Another back up!!) For the first time in forever, not a single 67-72 Chevy truck, Blazer, or Suburban on the property! Basically retired and getting the new Motorhome ready for some traveling. Doing a bit of work on the house getting it ready to sell! LOL!!

01-30-2009, 09:28 PM	#15
100%Chevy Registered User Join Date: Jun 2008 Location: Moss Point,Ms. Posts: 1,439	Re: valve adjustment I use the book "How To Rebuild Your Small Block Chevy" Probably the most used book on the market.Although a little dated now,it's still the single best source of information on small block Chevies. It calls for 3/4 turn after slight resistance.This is a starting point for me.After starting and warming the engine,I will loosen each(keeping up with the amount I turn the nut)until I hear noise,then re-tighten it till the noise stops.Sometimes it's more,some less.I do this several times on all of them. On new engines,you may have to do it again later.On worn engines,some lifters may be too weak to ever be quiet!New parts time! Mike.



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