pushrods

[highflyer]

I would like to check length and preload on a stock mopar head using stock shafts and rockers..i have 1968 rockers and shafts in the motor I used them because they were like new when I took them out of another motor..does anyone have knowledge of a tech article I can follow that tells how to..tx as always..j

 

[67Dart273]

Is the intake manifold off?

 

[highflyer]

yes...heads go on tomorrow...

 

[67Dart273]

Would be easier with intake removed. If the lifters are used and full of oil this could be a PITA

But you can get a fairly workable idea by checking "the 4 corners" of the engine. As if you are setting solid lifters, use the "EIOC" method, that is

Bump the engine until the EXHAUST just starts to OPEN and check the intake on that cylinder

Then bump the engine until the INTAKE has opened and is nearly CLOSED and set the exhaust for that cylinder

Measure the height of the valve retainer with a dial caliper, etc so you know what it is "closed."

Then stack feeler gauges under the rocker until you have the lifter bottomed but the valve is still closed. The stack of feelers will give you the depth at the valve IE 1.5 X the lifter movement

The trick with the intake on and with used, oil filled lifters, is to get them to bleed down and make sure they are bottomed, and to "not" open the valve.

Unless you've had the deck / heads milled, that is, if you are using "a standard" combination, you 'should' be OK

 

[rumblefish360]

A pushrod length checking tool is what you would use.

A place like highes engines will rent you the tool (pricey)) but also take that amount off the price of new pushrods.

 

[moper]

If it's just preload you want just install them all with the rockers and shafts, and when each lifter is on the base circle of the cam (not on any part of the lobe's ramps) use a wire-type feeler gage and see what you have for preload on them. It vary depending on the accuracy of the deck and head surfaces so youshould check all of them. You don't have to be exact - for stock type lifters the specs are anywhere from .020-.050+.

 

[67Dart273]

Chareist I don't know how I misread that.

 

[highflyer]

right now the motor is still ion the stand..intake off so I have easy access to turning over motor and measuring..no oil in the pan yet..

 

[highflyer]

Did a preload today....loaded the new lifters and marked the pushrod then unloaded them but held them and marked them again...had about .06 not quite halfway in lifter plunger travel ..then put an indicator on all of them one at a time and found 4 within .004 tir and the rest from .007 to .015.tir....none straight..then did a cam degree since I got a new cam wheel in the mail yesterday...all in all fun stuff..learned a lot..then went in and ordered new push rods..thanks for all the help..after reading fabo I remembered comp has a little phamphlet with preload and degreeing instructions with their cams..used it and the info on fabo and all went well..now im out of work till the push rods get here...thanks for all the help..j