WeGotMud

Projects & Parts => Garage/Tech => Topic started by: Kyle on March 26, 2011, 06:38:15 PM

Title: valve lash
Post by: Kyle on March 26, 2011, 06:38:15 PM
i have a set of roller tip magnum rockers for my 400 sbc. what its the gap that i would need between the roller tip and valve?
Title: Re: valve lash
Post by: bigmud44 on March 26, 2011, 06:55:50 PM
adjust like you normally would if its hydrulic if its solid go by cam card
Title: Re: valve lash
Post by: old school truck dude on March 26, 2011, 07:07:56 PM
Hydraulic gets zero lash plus 1/8 - 1/4 turn, I like 1/8 better too loose than too tight! Solid lifters like he said up there, ya gotta go with what the cam specs call for. ;D
Title: Re: valve lash
Post by: Wild One on March 26, 2011, 11:03:23 PM
Quote from: bigmud44 on March 26, 2011, 06:55:50 PM
adjust like you normally would if its hydrulic if its solid go by cam card
Quote from: old school truck dude on March 26, 2011, 07:07:56 PM
Hydraulic gets zero lash plus 1/8 - 1/4 turn, I like 1/8 better too loose than too tight! Solid lifters like he said up there, ya gotta go with what the cam specs call for. ;D

What they both said.
Your "lifters" determine valve lash needed
Title: Re: valve lash
Post by: Kyle on March 26, 2011, 11:30:26 PM
its a hydralic lifter sorry. flat tappet
Title: Re: valve lash
Post by: Kyle on March 26, 2011, 11:35:54 PM
arent ya supposed to be able to run a check guage/shim in between the roller and valve to set it?
Title: Re: valve lash
Post by: cnoswalt78 on March 27, 2011, 12:02:15 AM
feal the spring with your pushrod and stay at the top of it, (lifter) then adjust what your cam card says./or there is the spin the push rod method,untill ristance is fealt. Then adjust (fine tune) you just dont want it to loose or to tight. (just incase you dont have a cam card)

Posted by: Kyle 
Insert Quote
arent ya supposed to be able to run a check guage/shim in between the roller and valve to set it?
YES, if you have a cam card, get that gauge out and adjust, or get them close and adjust wile running(old timers used to do it)
Title: Re: valve lash
Post by: Jjay78 on March 27, 2011, 05:28:48 AM
hyd is supposed to be 0 lash, spin the push rod till ya feel it snag a lil, then another 1/8,
Title: Re: valve lash
Post by: old school truck dude on March 27, 2011, 12:23:28 PM
Lash is the measurement of the distance between the tip of the valve and the rocker. Zero lash means zero distance. Get them close before you start the motor by bumpin the motor around to get the cam's lobe side DOWN (valve closed) on each valve and tighten down the rocker nuts until most of the play is gone and do not over tighten or you will put a valve into a piston which will bend it, which really sucks. Theres not much space there to begin with, so be careful. They should all have about the same number of threads showin above the nut on your rocker stud. Start motor and tighten all the valves till all the clicking stops. Make sure you do not overtighten the valves! Go through and loosen each valve till it clicks then tighten till it stops clicking. Once the motor is quiet, go back through all the valves, loosen each one till it clicks, then tighten till it stops, then go 1/8-1/4 turn tighter on the rocker nut. Do not go any further than 1/4 turn, I dont care what any book or anybody tells ya. Have plenty of oil on hand and keep checkin it because it will be goin on the floor unless you make an old valve cover with a long slot in the top so you can adjust the rockers through the slot, that will help keep the oil from goin all over.  This aint hard, its OLD SCHOOL valve adjustment. ;D
Title: Re: valve lash
Post by: old school truck dude on March 27, 2011, 12:36:25 PM
Quote from: Kyle on March 26, 2011, 11:35:54 PM
arent ya supposed to be able to run a check guage/shim in between the roller and valve to set it?

No. That is on solid lifters.
Title: Re: valve lash
Post by: Kyle on March 27, 2011, 02:54:06 PM
Quote from: old school truck dude on March 27, 2011, 12:23:28 PM
Lash is the measurement of the distance between the tip of the valve and the rocker. Zero lash means zero distance. Get them close before you start the motor by bumpin the motor around to get the cam's lobe side DOWN (valve closed) on each valve and tighten down the rocker nuts until most of the play is gone and do not over tighten or you will put a valve into a piston which will bend it, which really sucks. Theres not much space there to begin with, so be careful. They should all have about the same number of threads showin above the nut on your rocker stud. Start motor and tighten all the valves till all the clicking stops. Make sure you do not overtighten the valves! Go through and loosen each valve till it clicks then tighten till it stops clicking. Once the motor is quiet, go back through all the valves, loosen each one till it clicks, then tighten till it stops, then go 1/8-1/4 turn tighter on the rocker nut. Do not go any further than 1/4 turn, I dont care what any book or anybody tells ya. Have plenty of oil on hand and keep checkin it because it will be goin on the floor unless you make an old valve cover with a long slot in the top so you can adjust the rockers through the slot, that will help keep the oil from goin all over.  This aint hard, its OLD SCHOOL valve adjustment. ;D
Quote from: old school truck dude on March 27, 2011, 12:36:25 PM
Quote from: Kyle on March 26, 2011, 11:35:54 PM
arent ya supposed to be able to run a check guage/shim in between the roller and valve to set it?

No. That is on solid lifters.

ahhh  gotcha. the way you described it was the way i was gonna do it but i saw on one of the horsepower shows that used shims, i just didnt know if it was hyrd or solid or anything. i do have some old tall valve covers i was gonna drill dome holes in the top to fit a socket down in to adjust it
Title: Re: valve lash
Post by: old school truck dude on March 27, 2011, 05:36:46 PM
They put shims under the valve springs sometimes to change the amount of pre-load on the spring, make them all the same
Title: Re: valve lash
Post by: the harvester on March 28, 2011, 12:18:51 AM
dont drill holes in them you have to cut the top off to feel your pushrods ++peace
Title: Re: valve lash
Post by: old school truck dude on March 28, 2011, 11:27:19 PM
If you havent installed the intake yet, you can see the lifters. They have a little dish in them, and it works likes a shock absorber. When there is no play left in the valve train, the pushrod will start pushin that little dish thing down. The pushrod spinnin method can get ya jammed up by overtightening, so dont completely rely on that. Just make sure the lifter is all the way down and get it close enough to fire up and go from there.
Title: Re: valve lash
Post by: Kyle on March 29, 2011, 07:15:52 AM
Quote from: old school truck dude on March 28, 2011, 11:27:19 PM
If you havent installed the intake yet, you can see the lifters. They have a little dish in them, and it works likes a shock absorber. When there is no play left in the valve train, the pushrod will start pushin that little dish thing down. The pushrod spinnin method can get ya jammed up by overtightening, so dont completely rely on that. Just make sure the lifter is all the way down and get it close enough to fire up and go from there.

alright that makes sense. ill definately keep an eye out for that. thanks!
Title: Re: valve lash
Post by: 4x4xdodgeman on March 29, 2011, 04:16:31 PM
is this new lifters or all ready run motor just putting on roller rockers?
Title: Re: valve lash
Post by: Kyle on March 29, 2011, 04:17:36 PM
Quote from: 4x4xdodgeman on March 29, 2011, 04:16:31 PM
is this new lifters or all ready run motor just putting on roller rockers?

all new cam, lifters and pushrods
Title: Re: valve lash
Post by: 4x4xdodgeman on March 29, 2011, 04:55:18 PM
the best way to do this is.  with the intake off, turn the motor over so the lifter is on bottom of the cam,( you can adjust  as many that are on bottom of the cam)  look at the pluncher & push rod  tighten the rocker down until  the push rod dose not move up and down  no free play  then tighten 1/8 or 1/4 turn  but do bottom out the push rod in lifter   and do not puy your lifters in oil to soak!! put lube on the lifters where thay meet the cam and sides put then in.
Title: Re: valve lash
Post by: old school truck dude on March 29, 2011, 08:55:53 PM
Quote from: 4x4xdodgeman on March 29, 2011, 04:55:18 PM
the best way to do this is.  with the intake off, turn the motor over so the lifter is on bottom of the cam,( you can adjust  as many that are on bottom of the cam)  look at the pluncher & push rod  tighten the rocker down until  the push rod dose not move up and down  no free play  then tighten 1/8 or 1/4 turn  but do bottom out the push rod in lifter   and do not puy your lifters in oil to soak!! put lube on the lifters where thay meet the cam and sides put then in.

I'm sure you mean do NOT bottom out the plunger. You can make the motor much easier to start if you put each lifter in a couple inches of oil and use the pushrod to pump it up. Soakin them does absolutely nothing other than get them oily on the outside - definitely need some kind of lube on them, are you usin oil or white lithium grease? I would not bother with the extra 1/8-1/4 turn at this point, this needs to be done running by ear, its the only real way to do it right. Also, sometimes the plunger is stuck down in the lifter just a little bit before it gets pumped up, and if you add to the distance by giving it another 1/8-1/4 turn, youve actually given the equivalent of 1/2-3/4 of a turn by the time its all in, and bingo bango, you got a bent valve and you get to start all over for another $100 or more. Seen it too many times.  ;D
Title: Re: valve lash
Post by: old school truck dude on March 29, 2011, 08:57:06 PM
Im thinkin maybe it wouldnt hurt to make a tutorial post on this procedure, along with engine and head ID  ;D
Title: Re: valve lash
Post by: Kyle on March 30, 2011, 07:11:42 AM
ok, i was just plannin on using oil for the assembly of everything just so there isnt some mix of chemicals that dont agree with eachother or whatnot. just so its all the same. and i never realized the lifter had a plunger in ti.... thought it was all solid, cuz would that contribute to valve float?
Title: Re: valve lash
Post by: old school truck dude on March 30, 2011, 01:57:48 PM
Quote from: Kyle on March 30, 2011, 07:11:42 AM
ok, i was just plannin on using oil for the assembly of everything just so there isnt some mix of chemicals that dont agree with eachother or whatnot. just so its all the same. and i never realized the lifter had a plunger in ti.... thought it was all solid, cuz would that contribute to valve float?

Not so much.. More so if your valve springs are not strong enough for the rpm youre tryin to reach. You can mix oil and white lithium grease, no problem ;D
Title: Re: valve lash
Post by: Hammerlane on March 30, 2011, 04:16:18 PM
Listen to Old school trcuck dude.. he's pointing you in the right direction.
I have done them that way myself several times.