Adjusting hydraulic lifters

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[[File:Lifter exploded view.jpg|thumb|200px|right|Arrow points to check ball retainer]]
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[[File:Lifter cutaway preload.jpg|border|400px|left]][[File:Hydraulic Lifter.jpg|thumb|200px|right|Generic hydraulic lifter]]
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[[File:Lifter clips 002.jpg|thumb|350px|left|Three styles of lifter cup retainers. The [http://www.truarc.com/pdfs/Truarc%20Catalog.pdf internal C-clip type] is stronger and should be used especially with solid lifters or when "zero lashing" lifters]]
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<br><br><br><br><br><br><br><br><br><br><br><br><br>     
 
==Overview==
 
==Overview==
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The following is information and instructions on how to successfully adjust the preload on adjustable hydraulic lifter valve trains. For non adjustable valve trains, refer to instructions for the specific engine type.
  
The following is based on instructions originally from Crane Cams. It is recognized by many as being the "go-to" method of valve adjustment. This method also works on any OHV engine using hydraulic lifters that has an adjustable valve train. The possible differences are:
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==A word on the correct length pushrod==
*the firing order
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To obtain the correct valve train geometry, the correct length pushrod needs to be determined and installed before setting the lifter preload. Below are some things to check that could have changed the correct pushrod length:
*the order of the valves in the cylinder head
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*the amount of preload to use
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==A word on the amount of preload to use==
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Below are some things to check that could have changed the amount of hydraulic lifter preload:
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#Camshaft base circle diameter
 
#Camshaft base circle diameter
 
#Pushrod length due to wear or replacement
 
#Pushrod length due to wear or replacement
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#Lifter height due to different manufacturer
 
#Lifter height due to different manufacturer
 
#Change in rocker arm type or design, or ratio
 
#Change in rocker arm type or design, or ratio
The recommendation given below to use 1/2 to 1 turn past zero lash is based on what has been shown to work well in the past when using stock or performance hydraulic lifters. However, the amount of preload may be different, depending on the type and brand of hydraulic lifters being used. For example, there are Comp Cams and Rhodes lifters that are set much as a solid lifter is set. Always refer to the manufacturer's instructions first before proceeding.
 
[[File:Hydraulic Lifter.jpg|frame|Generic hydraulic lifter]]
 
  
[[File:Lifter cutaway preload.jpg|border|400px|left]]
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==How much preload should I use?==
<br style="clear:both"/>  
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The recommendation given below to use 1/2 to 1 turn past zero lash is based on what has been shown to work well when using stock or performance hydraulic lifters. However, the amount of preload may be different, depending on the type and brand of hydraulic lifters being used. For example, there are Rhodes lifters that are set using a feeler gauge- something that's traditionally reserved for solid lifters. Always refer to the manufacturer's instructions first before proceeding. If the manufacturer's instructions differ from those given here, follow the manufacturer's recommendations.  
==Firing order==
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==Should I "pump up" my lifters with oil before installing them?==
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Generally speaking, no. The lifters can be dipped into a container of oil but unless the manufacturer's instructions tell you otherwise, there's no need to pump the lifters up before installing them.
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There are some exceptions to this. For instance Rhodes lifters DO recommend their "original" lifters be pumped up prior to installing and adjusting them to 3/4 of a turn, or so the lifter cup is about 1/16" below the retainer. The Rhodes "V-Max" lifters are adjusted so the plunger is from 0.010" to 0.030" from being ''fully compressed''- quite different than 'normal' hydraulic lifters are adjusted.
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==Can I replace a damaged lifter with a new lifter?==
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Before you replace a lifter (which should only be done as a LAST resort), disassemble your lifter that is in question. You will see a cup, spring and check ball assembly snapped onto the bottom of the center "piston" or "plunger" of the lifter. Often all that has happened is the cup assembly isn't fully seated onto the piston.
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Remove the cup using a pick and see that the (tiny) spring and ball are there and that the ball isn't scored and that the seat on the piston that the ball seals, doesn't have any ridge or imperfections that would prevent the ball from seating properly.
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Shown above, top right, is a GM hydraulic roller lifter. Most current flat tappet lifters have the same internal construction as this roller lifter, although there are different styles. But as long as the styles are the same, the piston from one can usually be fitted into another body. The arrow shows the location of the cup, spring and check ball assembly mentioned above.
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A better choice if the lifter's piston is found to be unrepairable, would be to replace the piston from another identical lifter, and reuse the lifter body that has broken in to the lobe that it started life running on. The lifter foot and the cam lobe quickly wear in together to become a unit- using a new lifter risks wiping out the cam lobe. This is also why it is not recommended to replace a used set of lifters with a new set on a used camshaft.
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The lifter body ID and the piston OD are a very close tolerance fit- the closest tolerances in the entire engine. Because of this, there's a chance that one piston won't work the exact same as the original. As long as the piston doesn't fit too tightly, this won't be a problem in the vast majority of cases, but should be mentioned just the same. The clearance between the piston and body is what regulated the bleed down rate. But having a slightly different bleed down rate is much preferred over putting a new lifter onto a used cam lobe in this writers opinion.
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===Chevy OEM hydraulic roller cam and lifters===
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{{warning}}<blockquote>According to Crane's Director of Valvetrain Research and Development, Mark Campbell, valve lifts of more than 0.530 inch at the valve with a 1.5:1 rocker can allow the lifter to fall deep enough into the lifter bore (because of the lobe's small base circle) that the steel retainer can lose its grip on the lifter body. This allows the lifter to spin in the bore and destroy the camshaft.</blockquote>
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Crane sells a long travel lifter, [http://www.summitracing.com/parts/CRN-10535-16/ p/n 10535-16a] that will work for reduced base circle/high lift cams.
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==Before beginning you will need to know:==
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===The firing order===
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*[http://www.crankshaftcoalition.com/wiki/Category:Firing_orders Firing orders of various engines]
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*The Chevy V8 is <font size="4">1-8-4-3-6-5-7-2</font>
 
[[File:Chev sb bb v8 firing order.jpg|right|frame]]
 
[[File:Chev sb bb v8 firing order.jpg|right|frame]]
  
===You will need to know:===
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===The direction the distributor rotates===
*The firing order of the engine you are working on.
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*The small block Chevy V8 is <font size=4>CW</font>  
:The Chevy V8 is <font size="4">1-8-4-3-6-5-7-2</font> 
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===The order of the valves as they are located in the cylinder head===
*The direction the distributor rotates.
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*The small block Chevy V8 is <font size=4>E - I - I - E - E - I - I - E </font>  
:The Chevy V8 is <font size=4>CW</font>  
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Other engines can be found at the [http://boxwrench.net/specs_index.htm BoxWrench] site.
*The order of the valves as they are located in the cylinder head.
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:The Chevy V8 is <font size=4>E - I - I - E - E - I - I - E </font>
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<br style="clear:both"/>
 
<br style="clear:both"/>
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==The adjustment procedure==
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The following adjustment procedure is based on instructions originally from Crane Cams. It is recognized by many as being the "go-to" method of valve adjustment. This method also works on any OHV engine using hydraulic lifters that has an adjustable valve train. Some possible differences between various engines are the:
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*Firing order
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*Order of the valves in the cylinder head
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*Number of turns to set the preload
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*Distance of the plunger below the retainer
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==Adjusting hydraulic lifters for proper preload==  
 
==Adjusting hydraulic lifters for proper preload==  
  
==='''EO/IC Method''' ('''E'''xhaust '''O'''pening/'''I'''ntake '''C'''losing)===
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=='''EO/IC''' Method ('''E'''xhaust '''O'''pening/'''I'''ntake '''C'''losing)==
  
 
*'''In order to adjust the preload, the lifter must be properly located on the base circle or "Heel" of the lobe.'''  
 
*'''In order to adjust the preload, the lifter must be properly located on the base circle or "Heel" of the lobe.'''  
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==Resources==
 
==Resources==
*[http://www.crankshaftcoalition.com/wiki/Valve_train_points_to_check Valve train points to check]
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;Crankshaft Coalition Wiki articles:
*[http://www.crankshaftcoalition.com/wiki/Category:Firing_orders Firing orders]
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:*[http://www.crankshaftcoalition.com/wiki/Valve_train_points_to_check Valve train points to check]
*[http://www.crankshaftcoalition.com/wiki/Category:Adjust_valves Adjusting valves]
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:*[http://www.crankshaftcoalition.com/wiki/Category:Firing_orders Firing orders]
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:*[http://www.crankshaftcoalition.com/wiki/Category:Adjust_valves Adjusting valves]
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*[http://www.cranecams.com/pdf-tech-tips/hydro-lift.pdf Fast and Easy Way to Check Hydraulic Lifter Preload when using Non-Adjustable Rocker Arms] from Crane.
  
 
[[Category:Engine]]
 
[[Category:Engine]]
 
[[Category:Adjust valves]]
 
[[Category:Adjust valves]]
 
[[Category:Good articles]]
 
[[Category:Good articles]]

Revision as of 09:58, 14 March 2012

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