Rocker lash/torque settings

NukeGM/Ford

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2 trucks - 2 different results

1.
3 or 4 yrs ago, installed paxton, cam, thinner head gaskets, slow bleed lifters, 5/16ths pushrods, beehive springs. Torqued rocker arms to 26 ft lbs like manual says. Didnt do any lash adjustment or engine rotation.
Engine no has 12k plus miles on it, no issues/noise from valve train.

2.
New oem short block, slow bleed lifters, 3/8ths pushrods, single springs. Start up, runs smooth but a lot of valve train noise/clicking.
IR gun on headers show even temps on all cylinders.
Ive read on here some do lash adjustment but manual says just torque down.

Havent driven down the road yet.

Valve cover filters (under sheet metal) are gone.
Took covers off and there is no film of oil on the inside of the valve covers.
I would expect to see oil everywhere under covers from rocker movement.

I want to run the motor with cover off to see oil flow but dont want a mess either.
Does oil on these squirt out of pushrod/rocker hole or ooze?

PFA
 

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That flat, spongey stuff that is in the valve cover (baffles) is available in bulk at larger aquarium supply stores.
 
Great, now that non essential businesses are closed lol.
Thanks for aquarium tip.
Manual doesn't state to rotate to tdc either. Just to do it slowly and wait 20 mins to start
 
2 trucks - 2 different results

1.
3 or 4 yrs ago, installed paxton, cam, thinner head gaskets, slow bleed lifters, 5/16ths pushrods, beehive springs. Torqued rocker arms to 26 ft lbs like manual says. Didnt do any lash adjustment or engine rotation.
Engine no has 12k plus miles on it, no issues/noise from valve train.

2.
New oem short block, slow bleed lifters, 3/8ths pushrods, single springs. Start up, runs smooth but a lot of valve train noise/clicking.
IR gun on headers show even temps on all cylinders.
Ive read on here some do lash adjustment but manual says just torque down.

Havent driven down the road yet.

Valve cover filters (under sheet metal) are gone.
Took covers off and there is no film of oil on the inside of the valve covers.
I would expect to see oil everywhere under covers from rocker movement.

I want to run the motor with cover off to see oil flow but dont want a mess either.
Does oil on these squirt out of pushrod/rocker hole or ooze?

PFA
Where did you get that picture of my wife...
 
IF you happen to have some of the original valve cover material around to compare it with the stuff sold at the Aquarium shops, that would be good.

To be clear, I'm not talking about the bulk white cotton/Q-Tip stuff.

That would be bad to use.
 
Are the lifters installed correctly?
Their oiling hole needs to point toward the intake.
From the lifter, oil travels up the pushrod to the rockers.
 
With lash adjustment I thought you’re supposed to rotate assembly so that lifters are on the base circle of cam (lowest spot with valves closed) and tighten down the rocker till the push rod just starts to bind under it (rotate the push rod with fingers). Then tighten more by about 1/4-3/4 of a turn. Then rotate assembly to next set of valves and repeat. I would always go around a minimum of 2 times to recheck them. Being a hydraulic lifter design this will give the valvetrane a self maintenance of adjustment as things heat up / cool down / and wear.

If something is making noise (ticking) something in the valvetrane has extra clearance that it shouldn’t. Verify pushrod lengths and that the bearings and tips on the rockers are not excessively worn.

First I’ve heard of just a torque setting for rockers, sounds too vague for such a delicate variable adjustment.
 
The O.E.M. rockers aren't adjustable.

Using a torque wrench, simply torque down the nut on each of them and that's that, you are done.

Go grab a beer.

If you have installed aftermarket adjustable rockers, particularly when used with the O.E.M. high-bleed lifters, lash settings can be a bit tricky. Even with fast ramps like a roller cam has, you may think you are on the base circle when in fact you aren't.

I had problems with other methods but the one below ensures you ARE on the base-circle and provides very consistent results and has worked very well for me:

  • ONCE THE EXHAUST ROCKER STARTS TO OPEN THE VALVE, SET THE INTAKE. (Start of the Exhaust cycle BBDC)
  • WHEN THE INTAKE STARTS TO RETURN FROM FULL-LIFT, SET THE EXHAUST ON THE SAME CYLINDER. (Piston rising on compression stroke)


As far as number of turns goes, it depends largely on the thread pitch on the rocker adjuster itself.

If you are looking for more bottom-end power keep the lash on the loose side. If you want more top-end, tighten the adjusters down more. You can play around with adjustment here to your liking (within reason).

When I first got my Strikers and used the recommended lash, it left at least 75 horsepower on the table, if not more. The proper adjustment made a world of difference and took some experimenting (time).


Have fun.
 
The O.E.M. rockers aren't adjustable.

Using a torque wrench, simply torque down the nut on each of them and that's that, you are done.

Go grab a beer.

If you have installed aftermarket adjustable rockers, particularly when used with the O.E.M. high-bleed lifters, lash settings can be a bit tricky. Even with fast ramps like a roller cam has, you may think you are on the base circle when in fact you aren't.

I had problems with other methods but the one below ensures you ARE on the base-circle and provides very consistent results and has worked very well for me:

  • ONCE THE EXHAUST ROCKER STARTS TO OPEN THE VALVE, SET THE INTAKE. (Start of the Exhaust cycle BBDC)
  • WHEN THE INTAKE STARTS TO RETURN FROM FULL-LIFT, SET THE EXHAUST ON THE SAME CYLINDER. (Piston rising on compression stroke)

As far as number of turns goes, it depends largely on the thread pitch on the rocker adjuster itself.

If you are looking for more bottom-end power keep the lash on the loose side. If you want more top-end, tighten the adjusters down more. You can play around with adjustment here to your liking (within reason).

When I first got my Strikers and used the recommended lash, it left at least 75 horsepower on the table, if not more. The proper adjustment made a world of difference and took some experimenting (time).


Have fun.
I see now, it’s just a bolt instead of a stud with lock nuts. Never had the valve covers off on mine yet. Watched a few videos about the viper rocker arm geometry. It’s similar to modern 4-stroke dirtbikes needing shims (and sometimes longer pushrods in the case of a bigger cam that has a smaller base circle). I always thought that was a hassle, just might have to upgrade something else now, lol.
 

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