Skip to main content ↑ ↓
Topic: ford stock rocker arm & fulcrum oil groove orientation **SOLVED (Read 3051 times) previous topic - next topic

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

son is building a 351w.

i dont have the answer for him and am currently digging into the shop manuals for the illustration.


On pedestal rockers, the rocker to fulcrum mating surface there are two machined oil grooves on each item and they are in a somewhat V pattern.

the fulcrum rubs on the inside of the rocker which has the same pattern oil groove.

when installing the normal stock rockers,
which way does the oil groove orient?
do you oppose the oil grooves or align them,,,

in other words, do you "x" pattern them or align them?
 

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

Reply #1 –
I've been running roller rockers for 10+ years so I haven't even looked at the stock pedestal setup in about a decade. Maybe pop a valve cover on your Cougar and take a look?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

Reply #2 –
I forgot i have two sets of GTP irons with rockers.

the oil groove on the rocker to pedestal mating surface are "aligned",,,, V shape over top V shape.

you can put the fulcrum in either way,, one way is wrong, one way is right.

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

Reply #3 –
Judging by this diagram, it appears that the "v" would "point" to the valve spring.

X
1985 Mercury Cougar XR-7 - 5-speed 
One of 1,246 built

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

Reply #4 –
as a result of my bad opinion/advice my son's valve fulcrums are torn up now.

I am not sure why i did not find that particular illustration in my shop manuals.. i did not bother with my haynes.

I did an etch and sketch of what my logic was in my bad advice.
I figured that if you oppose the oil grooves, you are always carrying oil from the rocker to fulcrum because the two channels always intersect.
this is incorrect as shown in "CONDITION 2".

I guess what you want is the oil grooves to only line up once in a moment it time , the remainder of actuation the oil grooves are NOT intersecting.

still makes no sense to me but either way i am wrong.

also a pic of what happens when you get this wrong.

stage 1- you hear a good running motor

stage 2- you hear something,,, it sounds like a very faint but identical sound of a train brake system constant "sqeeeeek" likely in just one spot.
~my troubleshooting lead to an idea that a valve "single" keeper had come dislodged and was screwing with the geometry of a single valve and head guide because thats the only area i know of that could make such a high pitch noise he was hearing.  this also was substantiated because the noise was "up top" and on the pass side only.

stage 3-you will shut down and be a bit depressed, let it go over night then restart the next day to use a wooden dowel to pinpoint the noise.  When you start up you
will find now the noise is ***EVERYWHERE***  up top.

all is well though,, i sent him rocker/fulcrum/bolt replacements so it should be ok after today or tomorrow.

im not really sure why this small detail has evaded my attention.,,

there are tons of posts on this topic and all that we ran into say it does not matter,,,  my fault for not putting my own eyes on the topic to completion, i gave up cause i could not find the answer ~which was a dumb move on my part

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

Reply #5 –
Ill go out on a limb here and assume another thing,,

i believe now that the grooves are over top one another while the valve us "under load". 
i know thats not what i have drawn but..  it has no real bearing on the goal of this post...

it does though possibly answer "why" it works.
if my speculation is correct then while under load the grooves align and by gravity, the oil can "drain" into the two coordinated galleys.

all i know is that some engineer somewhere in the past must have had a long study on solving this puzzel,, finally found out this solution and said "screw it,, it works, stick with it,, and dont change it ever!".

ford stock rocker arm & fulcrum oil groove orientation **SOLVED

Reply #6 –
You are correct in that the oil drains from the "bowl" area on top of the rocker arm, down thru the aligned grooves between the fulcrum and the rocker body to provide needed lubrication at the friction point where the sliding movement of the rocker occurs.

The alignment isnt occuring under load(valve opening/closing) but rather in the static position when the valvetrain is not under load(on the heel of the cam) for a few reasons. One being time. There is a larger time window for lubrication to take place on the heel of the cam(valve spends longer closed then open), secondly, lubrication is better if it  actually occurs before the rocker movement not during, third, the static position has less load so the oil will flow more easily and evenly across the surfaces, fourth, the rocker is in a more horizontal position when its closed or static, then if its pointed downwards/open... so the small amount of oil that drains into the lubrication grooves will be better supplied from oil laying on top of the rocker in the "bowl", although this is probably more of an increased lubrication-at-engine-start consideration, since a good percentage of the rockers are going to be static or nearly so at any point of the engine being shut off or later on, when its restarted.