Setting hydraulic lifters

[chevynut]

Wanted to understand the correct way to set hydraulic lifters once installed in a new engine. The reason I ask is I have been doing some degreeing of my cam and when I tried to just take the lash out of the lifters, they collapsed as I turned the cam. If I set them up with the typical 1/4 to 1/2 turn after zero lash, will they be correctly set when the engine is fired up?

How do you prep hydraulic lifters for installation to make sure they're full of oil? Or do you have to do that?

I kind of understand how these things work, but how do you ensure the lifter is closing and opening the valve properly? It seems like there's at least .100" between pumped up and collapsed.

[JT56]

Wanted to understand the correct way to set hydraulic lifters once installed in a new engine. The reason I ask is I have been doing some degreeing of my cam and when I tried to just take the lash out of the lifters, they collapsed as I turned the cam. If I set them up with the typical 1/4 to 1/2 turn after zero lash, will they be correctly set when the engine is fired up?

How do you prep hydraulic lifters for installation to make sure they're full of oil? Or do you have to do that?

I kind of understand how these things work, but how do you ensure the lifter is closing and opening the valve properly? It seems like there's at least .100" between pumped up and collapsed.

A couple of questions:
Are we talking Hyd Roller or Flat? What kind of lifters? Also have you checked for correct push rod length? For instance my current roller lifter is a steel bodied short travel that doesn't need any oil and lash is set at 1/8 to 1/4. Several opinions out there but in the racing world...Pat Musi, David Reher, Steve Morris, Bullet Cams ect...Do it when the engine is cold, start with #1 and go in firing order. You want to adjust them when your on the base circle of the cam. When the Exhaust starts to open adjust the INTAKE and when the intake is about 1/4 from closing then you adjust the EXHAUST. I move the push rod up and down and start adjusting the rocker arm nut. When it doesn't move then that is ZERO lash and per manufacture that is where you get your 1/4, 1/2 or 3/4 turn. To start off, set it on TDC and start there. Both valves should be closed. After you get all the way around, 8 , 4 , 3, 6 , 5, 7, 2 you can do what I described above on #1. Put some assembly lube on each end of the push rod.

[chevynut]

Stock hydraulic GM roller lifters, stock pushrods. How can a hydraulic lifter not need any oil?

I understand the adjustment procedure as far as being on the base circle and know how to do that, but my question is related to having oil in the lifter. It's a little difficult to determine zero lash when the lifter collapses. That's why I wondered how to get oil into them. I read that some guys soak them in oil overnight and COMP recommends to soak them in oil after washing with solvent.

http://www.compcams.com/Instructions/Files/122.pdf

But others seem to contradict this:

"Below from Crane:
Tech Tips


Flat Tappet Going Flat? First of all, the hydraulic or mechanical flat tappet lifters need to rotate in the lifter bore to get an even wear pattern. This will keep the cam and lifters running smoothly. So, set up will be very important on a flat tappet cam. Spring pressure can be too high and not allow the lifter(s) to rotate in the bore during break-in. So if you are running dual springs, you will need to remove the inner springs to reduce the pressure on the lifters during break-in. Also, do not run a synthetic type of oil for break-in. Before the installation of the cam and lifters, do not soak or pump up the hydraulic lifters! This will only make the lifter lock up and cause more problems when setting a pre-load into the lifters


Northern Auto Parts:
Here are some Engine Rebuilding Tips

Need oversized pistons? make sure you match rings to the piston over-size
Never soak your lifters, just coat with a good cam lube prior to installation
When replacing your camshaft with a higher lift cam always buy matching springs
Remember to use Plastigage on your bearings to make sure of a proper oil clearance
When installing any bearing Do not Attempt to Polish The Bearing Running
Surface With Any Type Of Abrasive Pad Or Paper.
Use an Engine Break-in Oil Additive such as Comp Cam's



Below is from Comp:

It is
not necessary to “pre-pump” hydraulic lifters full of engine oil prior to installation and valve
adjustment. It is actually undesirable to do so as the “pumped up” lifters will cause the valves to open during the adjustment process, rather than positioning the lifter plunger in its operating position as it is supposed to do. “Pre-soaking” hydraulic lifters in a bath of engine oil is a good
idea but not mandatory.


Eddy states below:

Install the lifters using a high quality engine oil (5W30 or 10W30).
Briefly dip the lifters in fresh, clean oil just before installation. Do not
soak the lifters for a long period of time before installation."

http://www.nastyz28.com/forum/archiv.../t-187089.html

[Rick_L]

JT's method is the best one. Be sure that you're detecting zero lash by moving the pushrod up and down. Some people try to do that by rotating the pushrod and feeling for friction - but that's much less accurate.

The nice thing about the EO/IC method is that it works on any 4 stroke engine with any number of cylinders and any firing order. The only thing you need to know is the difference between an exhaust valve/rocker and an intake. You can adjust the valves in any order, all you need to know is when you've done them all.

Using a hydraulic lifter to check the cam timing can lead to error because the lifter can collapse while the valve is open, or if you intentionally collapse the lifter for checking purposes, your geometry is slightly altered. Best to use a solid lifter of the right length, or modify a hydraulic lifter for checking only by shimming it for zero travel.

As JT suggested, checking for proper pushrod length is a good idea too. You shouldn't have a problem there though.

[JT56]

[QUOTE=chevynut;32530]Stock hydraulic GM roller lifters, stock pushrods. How can a hydraulic lifter not need any oil?

I understand the adjustment procedure as far as being on the base circle and know how to do that, but my question is related to having oil in the lifter. It's a little difficult to determine zero lash when the lifter collapses. That's why I wondered how to get oil into them. I read that some guys soak them in oil overnight and COMP recommends to soak them in oil after washing with solvent.

Lifter Preparation: Remove your new COMP Cams® lifters from the packaging, and cleanthe lifters thoroughly in mineral spirits or an equivalent solvent. Remember, in order to protectyour camshaft warranty new COMP Cams® lifters must be installed on flat tappet cams. It isnot necessary to “pre-pump” hydraulic lifters full of engine oil prior to installation and valveadjustment. It is actually undesirable to do so as the “pumped up” lifters will cause the valvesto open during the adjustment process, rather than positioning the lifter plunger in its operatingposition as it is supposed to do. “Pre-soaking” hydraulic lifters in a bath of engine oil is a goodidea, but not mandatory. Doing so ensures that the lifters are adequately lubricated on theirouter surfaces prior to installation. It may also result in a quieter engine start up as the oil in thebath may displace some air from the lifter’s plunger reservoir. Coat the bottoms of all flattappet lifters with COMP Cams® Cam and Lifter Installation Lube (Part #103) supplied withflat tappet cams. When you install the lifters, make sure they fit well. Flat tappet lifters shouldrotate freely in the lifter bores. Any excess clearance or tight lifters can cause damage to thecamshaft, leading to engine failure. Note: .0015”-.002” lifter bore clearance is minimum.

Comp says not to soak them but to give them a bath. It not desirable to have to do it more than once. But I would not soak them and set to 1/2 turn and run it. Listen for valve train noise and adjust again if needed. You could do the same and dyno the motor and re adjust if necessary. Plus it would allow you to seat the new rings too. Most engine builders would like to have it on the dyno a few day to get several pulls before putting it in the car. Just my .02

http://www.compcams.com/Instructions/Files/122.pd

[JT56]

The nice thing about the EO/IC method is that it works on any 4 stroke engine with any number of cylinders and any firing order. The only thing you need to know is the difference between an exhaust valve/rocker and an intake. You can adjust the valves in any order, all you need to know is when you've done them all.

I have done it using the marks on ATI Balancer too. Yes can be done in any order...I just try to maintain consistency when I am doing it.

[chevynut]

So is it fair to say that the intent of the hydraulic lifters is only to take up the lash at the base circle, and at full lift they should be collapsed? That's the way I thought they worked. And that's the way I'm checking the valve lift.

Sounds like I should be sure the lifter is collapsed when setting the lash (by pushing down on the pushrod), but if that's the case and I turn it 1/2 turn more past zero lash the valve won't seat. That's where my confusion on this is. These lifters have to either be extended or collapsed to get the right reading, I would think. If it's not, there seems to be a "no man's land" where you don't know how much lift you're actually getting.

Any ideas how I could check the lift with a simulated .335" cam lobe? My cam only has .310" and .320" lobes. I want to know how much lift I get at different lobe heights so I can target a lobe to get .600" max lift at the valve.

[Rick_L]

A hydraulic lifter does not collapse during the valve opening event.

In a modern hydraulic lifter, a hardened steel push rod cup sits on top of a plunger mounted inside the hollow lifter body. A lock ring in the top of the lifter holds the assembly together. Under the plunger is a spring that holds the plunger up so oil can fill the cavity between the plunger and lifter body. A one-way check valve in the bottom of the plunger allows oil to enter the plunger cavity but traps the oil inside when the lifter moves up. This prevents the lifter from collapsing, which would not allow it to open the valve fully.

Google it, you can find more, as well as some images of how it's accomplished.

On the lift, you have already measured/calculated the rocker arm ratio (though you really should do it again with a checking lifter). Then the lift with the bigger lobe is just lobe lift * ratio.

You don't need to be any more accurate than that, if you think you do you're wasting your time.

[chevynut]

I have googled the operation of a hydraulic lifter and it seems it operates somewhere between fully extended and fully compressed. I don't understand how it can stay in that range, but I guess it does.

http://www.centuryperformance.com/va...procedure.html




The typical hydraulic lifter requires an adjustment that is roughly half the available travel of the plunger. If an average hydraulic lifter plunger has a range of 0.060" (sixty thousands of an inch) of travel from fully compressed to its static height where the pushrod seat is up against the retaining ring, half of that distance will be +/- 0.030" (thirty thousands of an inch). This means that we must adjust the valves to fall between the depth that the plunger in the lifter drops. If adjusted too tight (the plunger fully compressed) the valves stay open slightly, and do not close all the way. This removes the important cooling time (lash) that removes heat from the valve stem.
If the adjustment is too loose, the valvetrain will be loud, and damage may occur to the valve tip (top of the valve stem), rocker arm, push rod, pushrod seat, the lifter, and camshaft lobes.

How do we achieve a 0.030" or centered plunger depth? On newly assembled engines I will actually use a dial indicator and measure the distance of travel on the new lifter. On an complete engine, especially one already in the car this is harder to do.

I have two procedures that I use to adjust hydraulic lifters. One uses the "clean" method with the engine turned off, and the other is the messy way with the engine running and squirting oil everywhere. I prefer a "clean" adjustment, and only use the messy way as a last resort.

For the messy method I fabricate custom cut-up used valve covers, oil deflectors, and other techniques in an attempt to keep the oil in the engine. Preventing oil from splashing all over the engine compartment and off the ground can be an intense chore that takes consideration and planning!

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Engine "OFF" Hydraulic Lifter Adjustment Tips:


If the engine is complete and installed in the vehicle, warm up the engine by running it until it gets to operating temperature (15-minutes or so). "Cold" adjustments should only be used on new engines on as a preliminary adjustment on the engine stand. Once a new engine has been started and intial break-in procedures complete, readjusting the valves "hot" is recommended.

1. Have all necessary tools ready and then quickly remove the valve cover(s) while the engine is at operating temperature.
2. Begin the adjustment procedure by using the chart above, or one to match your firing order and opposites.
3. With the #1 Intake valve at FULL LIFT --- This means that you turn the engine by hand until the intake valve on the #1 cylinder is fully open (watch the rocker arm push down on the top of the valve stem, compressing the valve spring until it stops moving downward) --- and adjust the intake valve on "opposite in firing order" cylinder. Always remember, the opposite valve engine firing order dependent. Know your engine's firing order!
4. Go to ths opposite cylinder. This technical article uses the common firing order for small and big block Chevy engines as the example, so this would be the #6 cylinder.
5. Loosen the rocker nut (if using roller rockers there is typically a Jam Nut that you must first loosen with an Allen wrench) on the #6 intake valve.
6. Take two fingers and spin the pushrod back and forth between them to feel for resistance.
7. Carefully snug the adjustment nut and STOP when you feel resistance in the pushrod as it applies pressure to the socket in the rocker arm and lifter, this is considered "zero lash."
8. Turn the wrench 1/8 to 1/4 turn (see below) for performance, racing, or high RPM applications. Turn the wrench 1/4 to 1/2 turn for stock or mild street applications. For applications that regularly operate at consistent high RPM, use the slightly lighter setting of (1/8 turn).
9. If your valvetrain uses poly-locks, remember to reset (snug) the Allen screw
10. The adjustment for this valve is now complete!
11. Turn the engine by hand SLOWLY to the next cylinder / valve in the firing order.
12. Repeat the above steps, starting at #3 through #10, but use the next cylinder in the sequence. In our Chevy V8 example this is the intake valve for the #8 cylinder
13. Continue through all the intake valves and then start the procedure over for the exhaust.

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What is 1/4 turn? (see image below)



This is another area that has been taught wrong in auto shop classes and very expensive service manuals since the 1950's. Imagine the hands on a clock. You have the obvious 12:00, 3:00, 6:00, and 9:00 o'clock positions as well as the numbers in-between those points. Start with your wrench at the 12:00 position and turn it clockwise to the 6:00 position you have just made 1/2 turn. Going from 12:00 to the 3:00 position would be 1/4 turn. Many manuals say to adjust the valves three quarters to one full turn ... THIS IS INCORRECT!!!!

Perform this procedure the same way for all the intake valves, then adjust the exhaust valves the same way.

PRECAUTION: When working on older high mileage engines or those that use poor quality lifters you may experience a condition where the lifters bleed off pressure (drain the oil out of the lifter body), causing inaccurate valve adjustment. Oil must remain in the hydraulic lifter in order to achieve an accurate valve lash setting. If repeated attempts to adjust the valves using the "cold adjustment" procedure fails, lifters bleeding off may be the cause. two options exist to solve this issue. ONE: replace the lifters or TWO: adjust the valves using the "HOT" running method described below.

TIP: One way to tell if this is occurring (bleeding off or no oil) is by watching the rocker arm while applying the 1/8 to 1/2 turn of the wrench. If the rocker pushes the valve stem down instead of the pushrod, you are opening the valve instead of adjusting the lifter!

[chevynut]

[QUOTE=Rick_L;32537]On the lift, you have already measured/calculated the rocker arm ratio (though you really should do it again with a checking lifter). Then the lift with the bigger lobe is just lobe lift * ratio. [quote]

Well that's the issue. These COMP Magnum rockers aren't full rollers, so the ratio isn't constant (it isn't with full rollers either). Obviously you haven't read the stuff I posted from David Vizard's testing of these rockers . His testing showed that the factory rockers start out at 1.01:1 ratio and hit 1.679:1 at full lift (.600" ). The COMP Magnum rockers start out at 1.65:1 and have a ratio of 1.79:1 at full lift. Even the full rollers have varying ratio, though not as pronounced.

Look here on page 108:

http://www.centuryperformance.com/va...procedure.html

You don't need to be any more accurate than that, if you think you do you're wasting your time.

Of course I do. If I want to calculate cam lobe height for a maximum valve lift of .600" and assume the advertised rocker ratio of 1.72:1, I'd need a .349" lobe. If I use the actual 1.79:1 ratio that Vizard got in his testing, I'd need a .335" lobe. The .349" lobe would give me .625" lift. I think a .025" lift discrepancy is a pretty big deal.

That's why I want to check the actual ratio using my heads, pushrods, and rockers.