valve adjustment questions

Simple SOLUTION!!!...Check your valves BOTH intake & exhaust whilst COLD.

What is the gap/valve lash?

Then drive & get the engine "Hot"...Measure the gap/valve lash.

The answer should become "Self-Evident"...Mark

Some OEM manufacturers quote hot lash, others quote cold lash. The Boss 351 was quoted both ways by Ford, one in the owners manual, the other in the work shop manual. That can be confusing! However the manufacturers of aftermarket cams all quote "hot lash" as far as I know. Hot lash, i.e. when the engine is running, is a "real world" setting.

One thing that can be overlooked however, pay attention if the aftermarket cam grinder's lash clearance is specified at the lobe, push rod, or tappet. Lobe, push rod, or tappet lash must be multiplied by the rocker ratio if you plan to measure lash at the valve tip. It is quoted this way by some cam grinders because an aftermarket lobe may be used in an engine having 1.5:1 rockers, or in another engine having 1.8:1 rockers. The rocker ratio impacts the lash setting as measured at the valve tip. If its not stated that way, then assume the lash is quoted at the valve tip, and no multiplication is required. Most of the time hot lash measured at the valve tip will be in the 0.020" to 0.030" range, but some cam grinders offer aggressive race cam lobes that are "tight lash" lobes. Tight lash lobes will have a hot lash setting less than 0.020" (at the valve tip).

If the rocker arms are swapped for arms having a different ratio, the lash setting should usually be adjusted to reflect this change.

Even though its quoted "hot", the lash of any camshaft can be set cold too, using these guidelines:

(A) Iron block and iron heads: Cold lash = hot lash setting plus 0.002”
(B) Iron block and aluminum heads: Cold lash = hot lash setting minus 0.006”
(C) Aluminum block and aluminum heads: Cold lash = hot lash setting minus 0.012”

It's simple really. You have roller rocker arms.

The feeler gauge goes between the valve tip and the bottom of the roller. That's the clearance you are measuring.

The Ford shop manual shows an adjustment order. I use it.
Others say just adjust each valve as it comes up on it's firing order.
The Ford order, although more cumbersome, compensates for variations in cam timing.
On a mild cam it isn't so important. On a more radical it becomes more significant.

I'm not going to argue either way since with solid lifters, either method will get you where you want to go.

One thing that no one here has mentioned, probably because so many are too young to remember the "old days" is that with solid lifter cams you can dial in a little more bottom end or top end depending on what the clearances are set at. The maximum variation either way being about .002".

Tighter means more top end, less tight more bottom end. I doubt that your camshaft would be even noticeable either way though so "aim" at the manufactures specs.

Considering what I just said, it should become apparent that the specs really in effect are "approximate"?

First off, you do this with the engine off and not running. Secondly, if you can figure out how to keep this engine hot while you adjust the valves, all of them, you must have gotten access to NASA over the weekend, because while it is POSSIBLE it is very improbable to do.

Just do it on a day when the temps aren't supper cold like we have here in the northeast in our Siberian "spring time".

If you can get 70 to 75 F, then you're pretty close. Most laboratory test temperatures are attempted to be standardized at 70 degrees.

The number you are aiming at is going to be the spec set by the cam manufacturer. Doesn't matter much at all, hot or cold.

They say .020, then .020 it is.



After bringing up the valve to adjust, place you .020 feller gauge between the tip of the valve and the roller.

At this point IF the gauge just slides in AND you can just barely turn the push rod with your fingers, leave it alone and go on to the next valve.

There is no point in backing out the set screws and re-tightening them. The go/no go on these lifters is really about .001". Look at that feeler gauge in the assortment. It's thinner than a sheet of writing paper.

If the gauge won't go through at this point, then they are on the tight side, particularly if the engine is at "room temperature". Then you've got to go through the readustment procedure.



"(A) Iron block and iron heads: Cold lash = hot lash setting plus 0.002” (B) Iron block and aluminum heads: Cold lash = hot lash setting minus 0.006” (C) Aluminum block and aluminum heads: Cold lash = hot lash setting minus 0.012”


A & B I agree with EXCEPT Compcams told me .004" for the Cleveland and .006 is a BB Chevy. I never had an aluminum block so no opinion on that.

My Pantera 351c engine calls for .022 Hot. It has aluminum heads on a cast iron block. Stainless steel roller rocker arms on steel rocker arm studs.

The gap on the lash will GROW as the engine gets hotter. Comp cams says that number is very constantly .004".

That means I need to set the COLD GAP at .018". That will give me .022 HOT.

I would call them again to verify before you do it?


My iron head 347 is different. It calls for .022 hot and is set at .024" cold. Both seem to be just right?



In the case of something like a Ford 289hp with solid lifters, check them in something like the 12,000 to 15,000 mile range. If they start to sound louder than normal then it's probably time.

I don't see how you can notice that though. The noise volume of your engine at idle with the deck lid open might be in the 86 to 90 decibel range? Mine is about 82 depending on the angle I read it at.


Your setup with the added mass of the SOLID roller lifter valve train, mileage was not a serious consideration on adjustment intervals? I would think you might NEED to check them every 2 or 3 thousand miles? It's really very hard to say.


"Your mileage may vary".

quote:

Originally posted by George P: Even though its quoted "hot", the lash of any camshaft can be set cold too, using these guidelines:
(A) Iron block and iron heads: Cold lash = hot lash setting plus 0.002”
(B) Iron block and aluminum heads: Cold lash = hot lash setting minus 0.006”
(C) Aluminum block and aluminum heads: Cold lash = hot lash setting minus 0.012”

I think that’s a pretty good rule of thumb and pretty consistent with what I’ve seen. It’s a pretty well known phenomenon for pushrod engines and is caused by the difference in the coefficient of linear of thermal expansion between the metals over the distance of the cam centerline to the tip of the pushrod. The cam, lifters, and pushrods all being steel and then the block and head material differences and corresponding differences in thermal growth, which will always grow more that steel cam/lifter/pushrod combo.

If you look up the coefficient values and measure the distances for the various materials, then use the difference between fluid temperatures and ambient temperatures as a proxy for temperature change, you will get very similar values for change in lash.

On alloy block and head pushrod engines the increase in hot versus cold lash at valve tip will also be accentuated by higher rocker ratios and longer cam-PR tip distances. For iron/iron engines it’s almost a non-event but on ally/ally it can actually be a limiting factor on how tight you can run and is a major reason (among others) why you’ll see tight all alloy track engines staged with preheated block and oil sump heaters before being started so as not to risk bending a pushrod or damaging a roller bearing as they often can be at/near zero lash cold depending upon conditions.

On my 9.5 deck all alloy roller the difference between hot and cold lash is .011” (1.73 rocker ratio) measured after full soak dyno runs and then cold measurement in the morning. It’s only necessary to check the difference on a couple cylinders as it will be very consistent. Just start conservatively cold and get a couple good readings on an easily accessed cylinder for the hot read and you can set lash cold from there on without worry, or if you’re already on the road, get a good hot read on a convenient cylinder and measure same cylinder(s) cold and you’ll know.

Best,
K

Actually, to me, compared to every other solid lifter motor I've run into, this motor runs quiet as a mouse.

I remember hearing the ticking before hearing the engine on a couple cars a long time ago.

My motor runs extremely quiet IMO. I inspected the valvetrain when I had the covers off, but didn't measure (I was more concentrated on inspecting and getting the motor back together, plus, Roger said he had recently adjusted them, and they all felt close).

I expect everything is good, or very close to where it's supposed to be. Cam sheet says .020 I think.

I just want to adjust the valves myself, go through the motions, make sure everything is set perfectly, just part of my learning my car and part of the beginning of my never ending maintainance of the car.

FWIW, I hot-adjust my engines while they're running. Slide a feeler gauge between the rocker wheel & valve stem while manipulating an allen wrench for the internal setscrew. Follow immediately with a box-end wrench to lock down the setscrew about 1/8-turn, as humans cannot tighten the setscrew tight enough to hold more than a few seconds. Tightening the locknut will change the lash, so you can see this isn't easy to do "perfectly". It may not matter much, either.

A story: many years ago, a man invented a dial-indicator attachment for perfectly adjusting valve lash, and showed up at Ed Iskenderian's So-Cal race shop. He pushed Ed to endorse his invention. Ed had a Chrysler engine on the dyno, so he invited the guy in for a demo. Ed told his mechanic to "run the valves like we're at the track with 10 minutes between rounds. You know- kinda sloppy". Then they dynoed the motor.

Next, Ed let the inventor use his patented attachment & tools to carefully set all the valves; took him much longer. The next dyno test showed a LOSS of 50 horses. "Perfect adjustment" might not be what we need on old-school engines. The invention never sold well & the guy went out of business shortly thereafter. You still see the invention on E-Bay now 'n then.

I want to adjust the valves just because I want to do it.

The engine is running fine, but I know adjusting the valves is part of the maintenance, and it's something i haven't checked personally yet.

I want to learn how to do everything i can on my car that I can do myself.

I have the cam sheet, it says .020.

So as George P wrote, an iron block with aluminum heads would be hot lash (.020) minus .006?

Is that correct?

I'm not looking for perfection, more to learn about my car, and to adjust the valves and ensure they are all in check.

quote:

Originally posted by Bosswrench:
FWIW, I hot-adjust my engines while they're running. Slide a feeler gauge between the rocker wheel & valve stem while manipulating an allen wrench for the internal setscrew. Follow immediately with a box-end wrench to lock down the setscrew about 1/8-turn, as humans cannot tighten the setscrew tight enough to hold more than a few seconds. Tightening the locknut will change the lash, so you can see this isn't easy to do "perfectly". It may not matter much, either.

It doesn't sound like you have ever adjusted the lash on en engine equipped with Jesel rockers like Mike's engine has. The lash is adjusted at the pushrod cup NOT at the center like a standard roller rocker. There is a billet steel stand which bolts to the head. There are two smaller studs which are part of the stand that go through two holes in the rocker shaft .


Ron

I know PERSONALLY....INSTEAD of asking others their opinion/s.

BEST!!!...to go to the SOURCE!!!

Simple approach...Your engine is equipped with Jesel Rockers...

WHY NOT ASK Jesel!!!...GHEeeeeeeeeeeeeeeeSH!!!

From Jesel's website...


ROCKERS
What do you look for when setting roller geometry and sweep pattern?
We set our aluminum systems with a low pivot geometry which results in the majority of the sweep pattern occurring while spring pressures are at their lower range. The majority of roller travel occurs from zero lash to half lift which results in minimum roller travel for the duration of lift when spring pressures are greatest. At zero lash, the roller should start approximately .050” behind the center of the valve stem, sweep across center and end near the center at full lift.

What is the proper way to set valve lash?
Starting at #1 cylinder, rotate the engine until the #1 exhaust rocker just starts to open the exhaust valve. Set the valve lash on #1 intake rocker at this time. Continue rotating the assembly and stop when #1 intake rocker starts returning from full lift. The lash on #1 exhaust can now be set. Continue this procedure for the remaining cylinders following the engines firing order.

Do I have to torque the adjuster nuts?
We highly recommend using a torque wrench when setting valve lash. Our recommended torque setting for a typical 3/8-24 cup or ball style adjuster is 26-28 Lbs-Ft. Over tightening the adjuster nut stresses the thread area in the rocker body leading to premature rocker arm failure.

Are there any break-in procedures I need to follow?
The most critical step in initial start-up is the proper break-in of the adjuster cup to pushrod tip surfaces. We supply a high pressure lube with all rocker kits to prevent premature failure and wear of the adjuster cup area. The shaft bearings are fully lubricated from Jesel and only require splash lubrication once running.

My adjuster is screwed fully into the body and I still can’t get lash. Can I drill out the body and sink the adjuster?
NO! We see more rocker failures due to this procedure. Invest in shorter pushrods or if it’s an emergency, raise the stand slightly. NEVER modify the adjuster cup counter-bore area.

How far out can I run my adjuster?
We recommend not running the adjuster turned out more than two revolutions from the fully seated position. All rockers are shipped from Jesel with the adjuster set at one full turn from seated. Operating an engine with the adjusters more than two turns out puts excessive loads on the cup area and may lead to premature failure of the adjuster.

When should I be running needle bearing nose rollers?
We highly recommend needle nose rollers on any application using 5/16” diameter or smaller valve stems. Open spring pressures and valve lifts are also factors to look at when ordering a rocker system. We have what we call our 800-800 rule. Any application running more than 800 lbs open or over .800” worth of total valve lift should be running needle nose rollers.

My rockers are rubbing the retainers. Can I relieve the area for extra clearance?
Yes, it is safe to remove a small amount of material from the underside of the rocker to gain additional clearance between the body and retainer. We recommend using a ball type end mill and not something like a “fly-cutter” which will leave sharp edges. Stress fractures can occur if sharp edges are left after machining so be sure to round all sharp edges. We can provide this option when rockers are being manufactured.

When should I replace my rocker arms?
There is no set time to replace a rocker arm body and generally there are many factors involved such as spring pressures, operating temperatures and the occasional over-rev. Aluminum bodied rockers will fatigue over time and varies by application and operating environments. One of the first signs of fatigue is the failure of the body surrounding the adjuster.



ROCKER GEOMETRY

Rocker geometry is a function of the arc generated from the rocker arm and the relationship of the valve tip to rocker shaft height. Using this arc correctly is the difference between a smooth operating valvetrain and a valvetrain of worn out parts. Jesel’s Low Pivot geometry utlizes the portion of the arc that produces a minimal sweep pattern from half to full lift, a point at which spring pressures are exponentionally increasing. These added spring forces transferred against the nose roller have the potential to cause the roller to skid instead of roll across the tip bending the valve stem and wearing the guides. By minimizing the roller travel distance under high spring loads, the potential of roller skidding is reduced and valve guide wear increased tremdously. As illustrated below, the Jesel Low Pivot geometry yielded almost .020” less roller travel during the critical stages of lift compared to a rocker set up for a symmetrical half-lift geometry.



BELT DRIVES
How often should I change my belt?
For V8 drag race applications, we recommend changing the belt after about 250 passes. For any type of oval track or endurance applications, the belt should be changed when the engine gets freshened. If you experience any engine failure that may have even temporarily locked up the rotating assembly, change the belt, its cheap insurance.

Is it OK to clean the belt?
The belt can be cleaned with mild soap and water detergents. Never use harsh chemicals such as lacquer thinner, brake clean or mineral spirits. If the belt gets saturated with engine oil, we recommend replacing it.

Should I cover my belt drive?
If you are running your engine on an abrasive surface such as a dirt track, it is highly recommended to shield the front of the drive to keep dirt and debris from damaging the belt and pulley surfaces.

How much camshaft endplay is acceptable?
On belt drives with adjustable thrust plates, we recommend running approximately .010” camshaft endplay. Excessive amounts of endplay can cause premature lifter failure while not enough will limit the amount of oil reaching the thrust surfaces. We have cam adapters available for certain models which utilize a needle bearing thrust assembly instead of bronze thrust washers. The needle bearing assemblies can be run down to as little as .001” worth of camshaft endplay.

How much belt backlash is acceptable?
Due to the round tooth profile inherent with the Gates HTD® timing belt, belt backlash between 2° and 4° degrees is acceptable and normal under a fully assembled valvetrain. If you experience backlash greater than 4°, it may be necessary to use an undersized belt or oversized upper pulley. Jesel stocks undersized and oversized belts for all applications.

Should I oil the crank seal before installing the lower pulley?
The seals used in our belt drives are Teflon® coated and should be installed dry for proper break-in. You should not oil the seal area on the lower pulley or the cam adapter.

Will my cover fit without modifying the block?
We try to make our belt drive covers as universal as possible and have it bolt on to several applications, but due to the vast number of aftermarket blocks that are modified from OEM prints, it may be necessary to machine the block for additional clearance. We highly recommend test fitting the components before any final assembly work is completed.

MY block has been aligned bored. Can I still use a belt drive?
The belt drive cover plate locates off the OEM dowel pins and is set to the factory cam to crank centers. The material used in the seals can adapt to a cam to crank center that varies by as much as ±.015”. If your block has been aligned bored more than .015”, you will need to remove the dowel pins and allow the cover to center itself off the installed lower pulley and cam adapter.

Will I have to use a degree wheel to set cam timing?
It is highly recommended to degree in the cam using a high quality degree wheel. The alignment dots on the upper and lower pulley are for general reference only. We have seen too many discrepancies in the placement of dowel pins and keyways in aftermarket camshafts and crankshafts.

How do I adjust cam timing?
For our 2 piece cam drives, loosen the four upper pulley nuts and rotate the crankshaft clockwise to retard or counter-clockwise to advance the cam timing. To adjust the timing on our solid upper pulley drives, you will need to remove the upper pulley and rotate it to the appropriate degree mark. Always check to see that the engine has adequate piston to valve clearance before altering cam timing.



LIFTERS
What type of oil should I use?
We recommend soaking the lifters in mineral based oil prior to installation as well as pre-lubing the engine prior to startup. After initial engine break-in, if you are going to use synthetic based oil, we highly recommend oils containing high zinc content formulated for racing applications. Synthetic oils formulated for street use are not recommended due to a lack of zinc content.

Do your lifters have a pressurized oiling circuit?
Yes, all of the lifters we manufacture since 1995 have an internal oiling circuit that feeds pressurized oil to the needle bearings in the roller insuring constant lubrication and elimination of any contaminants. There is also a feed hole that sprays oil to the outside diameter of the roller to help prevent cam lobe wear.

Should I be running oil restrictors?
No. Let the lifters be the restrictors. With the spring pressures and ratios being used in today’s racing engines, the lifters need as much oil to them as they can possibly get. Whenever possible, we suggest plumbing the block so that oil is fed equally to the lifters through the front and rear of the oil galley. In the event that you are getting excessive oil to the top end, provisions should be made for better oil drain back to the pan; either by external scavenging lines or internal drains.

How much lifter-to-bore clearance should I be running?
For a cast iron or bronze bushed blocks, we recommend running +.002” clearance cold. If you are running your lifters in an aluminum block without bushings, we recommend running +.0012” clearance cold and preheating the block prior to startup.

What is the advantage to using a larger diameter roller?
The larger the diameter, the stronger the roller. This is due to an increased cross sectional area between the I.D. and the O.D. of the roller. Also, a larger diameter roller rotates slower and reduces the loads needed to open the valvetrain. You may have to adjust your cam specs when using a larger diameter roller due to an increase in duration. A larger diameter roller may allow you to get more aggressive with your opening ramp design.

Why are your lifters so expensive?
The cost is a result of the highest quality materials being produced in small, quality controlled lots held to tolerances as low as .0001” of an inch. All components, with the exception of the needle bearings, are manufactured in our Lakewood, NJ facility on dedicated CNC machining centers and processed using the latest aerospace coatings and heat-treating procedures.

Why are your pushrod seats so low?
The closer the pushrod pivot point is to the bottom of the roller, the less leverage there is for the body to “rock” in the lifter bore. Think of it this way, if you’re trying to tip something over, the higher you push, the easier it gets.

I don’t see a snap ring holding in the axle. How is the axle held in?
All Jesel lifters feature an internal locking pin that secures the axle to the body. With our design, external snap rings and spirolocs that occasionally come loose causing severe engine damage is eliminated.

When should I replace my lifters?
Unfortunately there is no set time. There are many factors to consider such as operating environment, oil used and valvetrain stability. With proper care and maintenance, it is not uncommon for a lifter in a circle track application to see 2000 miles and a drag car with hundreds of passes down the strip. Jesel can inspect your lifters and provide you feedback on the expected life.

Can my lifters be rebuilt?
Most lifters purchased after June 2007 can be fully rebuilt. The procedure takes about a week and is only done here in our Lakewood, NJ facility. Due to design changes, we do not recommend rebuilding lifters purchased prior to June 2007.

COMPANY NEWS
INSTRUCTIONS
TECH TIPS & FAQ
LOGO DOWNLOADS
APPAREL
CONTACT US
CUSTOM SHOP
CPR
NITRO ALCOHOL
V-TWIN

I don't know anything about Jesel, except they will send you a REALLY nice printed catalog very quickly. You can order it from their web site.

In the FAQ in the hardcopy catalog is all the info Mark posted, so you don't have to keep running back and forth between your car and computer.

The catalog is filled with pictures of awesome looking engine parts, too.

The price list can bring a tear to your eye, as well.

Rocky

Go talk to these guys. Use their instructions Then it won't ruffle so many feathers.

You make your adjustments at the push rod but you measure the clearance under the roller at the valve tip.

You CAN NOT do that with the engine running.

http://www.jesel.com/valvetrai...YwQKTDHW3RoCmJ3w_wcB

That pic looks like the rockers I have except my heads have the cradles for the shafts cast into the heads I believe.

Adjusting looks easy and straightforward.

Nice setup.

You're right, Ron- I forgot Mike's engine has Jesel shaft mounts, not stud-mount rockers like most of us.

quote:

Originally posted by mike the snake:
That pic looks like the rockers I have except my heads have the cradles for the shafts cast into the heads I believe.

Adjusting looks easy and straightforward.

I don't know which is better or which one is the newer design.

I like the spring pockets.

Ron and I are going to tackle adjusting the valves tomorrow morning.

Driving the car, I do hear a couple "clickers", one or 2 that are louder than the others, but I'm going to measure first what everything is set at and take notes.

I got cold setting numbers from Comp Cams and Jesel, so hopefully the settings will be close already, and I'll just need to adjust the couple that are out of spec.

We will see tomorrow morning.

It's important to keep notes on what the valve settings are before you reset them. It's also important to note if there are any that won't keep the setting for very long.

If there are some that are constant offenders, replace the rocker arms with new ones at that location.

That could be an indication that you are loosing a bearing in that rocker arm. You don't want another failure.

It would also be NICE to pull out each and every push rod as well and examine the tips as well as check for straightness and any other abnormalities.

You are running high spring rates according to the timing card and you need to be as comprehensive as you can on these things.

You probably will be better off with 3/8" diameter push rods vs. 5/16".

You might want to install an aircraft "total hours running" gauge for this engine? That's going to be more important than mileage. It helps you keep track of what's going on with the engine.

quote:

Originally posted by PanteraDoug:
It's important to keep notes on what the valve settings are before you reset them. It's also important to note if there are any that won't keep the setting for very long.

If there are some that are constant offenders, replace the rocker arms with new ones at that location.

That could be an indication that you are loosing a bearing in that rocker arm. You don't want another failure.

It would also be NICE to pull out each and every push rod as well and examine the tips as well as check for straightness and any other abnormalities.

You are running high spring rates according to the timing card and you need to be as comprehensive as you can on these things.

You probably will be better off with 3/8" diameter push rods vs. 5/16".

You might want to install an aircraft "total hours running" gauge for this engine? That's going to be more important than mileage. It helps you keep track of what's going on with the engine.

"total hours running" gauge...Mike is NOT Major Tom!!!...Mark

https://www.youtube.com/watch?v=pXSGocWifAg