What's the correct method of tightening the rocker arms?

Tiny
SHJONMC
  • MEMBER
  • 1964 MERCURY COMET
  • 200,000 MILES
W/ manifold on can I follow the 460s rocker arm 3 step assembly seq since firing order's Im trying to correctly assemble(tighten) the rocker arms on a 289. Ive followed chiltons (which says tighten to 17-23lbs when lifter is at the bottom or on the base of cam shaft. Had the intake manifold off when I did this. The top of the nuts on the studs at 23 lbs was approx.

Half inch down the stud and it seemed a bit tight looking at the spring compressed and all so I asked a friend who had me back them all out to where the rocker arms were just tight enough to where if I lifted on them the rods would respond, with no play as far as putting a feeler gauge between the arm and the top of the spring. When starting my comet after that the starter never seemed to really kick so after changing batteries and getting same results I looked at a old ford manual which didn't have the 289, but had the 302, which said the same thing as the chiltons.

I noticed the 460 had the same firing order and listed out a three step procedure, adjusting various intakes and exhausts with each step. We figured it would be the same if the firing ord weer was the same and since I already put the manifold back on, thought that would make it easier. So I did exactly what it said starting with the crankshaft on tdc at end of compression stroke and the adjustments thereon.

Torqued to 20 lbs the arms were back a half inch down the studs and feel tight. And now my battery with 14+ volts just clicks, so obviously I have it too tight, right? Thing is, I could swear when I disassembled them, the nuts were down that far, cause my regular socket wasn't working and had to get a deeper socket 5/8 to get the job done. 20 lbs torque brings the nuts just beyond the reach of the regular socket, so seems that would be correct. So why does it seem to be so tight or am I just looking at this wrong.
Sunday, May 20th, 2012 AT 4:16 AM

6 Replies

Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
WANNA KNOW WHAT "LOCKS" THE NUT ON THE STUD WHEN YOU DO SCREW IT DOWN? (LOCK NUTS?)

ARE YOUR LIFTERS FULL OF OIL. WITH THE ROCKERS ARMS BACKED OFF, ARE THEY STILL "SPRINGY" WHEN YOU PUSH THE PUSH-ROD INTO THEM?

IF THEY ARE--GIVE ME AN ACCURATE IDEA HOW MUCH SPRING TRAVEL THEY HAVE

ALSO, CHECK ALL OF THEM FOR SPRINGY-NESS

WITH THE ROCKER ARMS OFF, WILL THE CRANK WITH A RATCHET (NO NEED TO ROTATE IT A LOT, JUST WANNA MAKE SURE IT'S NOT LOCKED DOWN)

LET ME KNOW WHAT YOU GOT

THE MEDIC
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Sunday, May 20th, 2012 AT 5:43 AM
Tiny
SHJONMC
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I rotated the crankshaft by hand from tdc at end of compression stroke 180 deg. Clockwise Then the 270 deg. It started getting pretty stiff getting it around to the third pos. So I bumped it the rest of the way tapping the relay. When I backed the nuts off there is that 1/8 inch of spring pushing the rod down into the lifters.
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Sunday, May 20th, 2012 AT 6:20 AM
Tiny
CJ MEDEVAC
  • MECHANIC
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ARE THEY PRIMED WITH OIL?

I SORTA HOPE THEY ARE NOT!

DO YOU HAVE A DIAL INDICATOR. NOT A DIAL CALIPER

THE MEDIC
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Sunday, May 20th, 2012 AT 6:27 AM
Tiny
SHJONMC
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I assembled everything with lucas assembly lube and I made the misttake of putting too much lube in the lifter the first couple and noticed the problen so I was careful not to do any like that. I soaked up the oil in the first couple and continued. Now when I had backed the nuts off to where the arms were just touching but no gap between arm and spring like I dwscribed initially, I did turn tbe engine over a few times trying to start it. Thats when the staeter was a bit sluggish and started switching batteries. I dont know if that would have filled the lifters with oil after those few cranks or not. Not sure what you mean by dial indicator. You mean like dwell meter or you talking my instrument panel, in which case would be yes, a dial
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Sunday, May 20th, 2012 AT 7:12 AM
Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
To adjust these correct ly you need to know if theyare hydraulic or mechanical first. If you adjust mechanicals like hydraulics you'll runinto trouble. If they are hydrulic once they are at zero lash, meanning all theplay from the pushrod then turn thme down one turn. That should take care of it. If these are the type that are on a rocker shaft then you torque them down and leave it. 289's if memory serves me correct aren't like that. I have info a t home but won't be there until late tommorrow.
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Sunday, May 20th, 2012 AT 12:43 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
CAN YOU SEND ME SOME PICS OF A ROCKER ARM INSTALLED ON YOUR HEAD

I WANT ONE OF THE BOTTOM SIDE AND ONE ON THE TOP SIDE

WHAT I WANT TO SEE IS IF THE ROCKER ARM PIVOT IS RESTING ON ANOTHER NUT ON THE BOTTOM SIDE OF THE STUD, IF IT RESTS ON THE PEDESTAL WHICH THE STUD IS SCREWED INTO, OR IF IT IS "SUSPENDED" SOME WHERE ON THE STUD WITH ONE TIP ON THE VALVE AND THE OTHER END ON THE PUSH ROD

A DIAL INDICATOR IS A BASICALLY A "CLOCK" GRADUATED IN THOUSANDTHS OF AN INCH WITH A PLUNGER OUT OF THE SIDE OR BOTTOM--AS THE PLUNGER GETS MOVED THE "CLOCK" MEASURES HOW MANY THOUSANDTHS OF AN INCH IT MOVED. THIS MIGHT BE HELPFUL IN SEEING EXACTLY HOW MUCH "SPRINGY" YOU HAVE IN A TAPPET (LIFTER). (YOU SAID ABOUT ONE EIGHTH, A DIAL INDICATOR WOULD READ.0125, IF YOU WERE "DEAD ON" OR TO BE REALISTIC MAYBE YOU WERE OFF AND IT IS REALLY (EXAMPLE).0142)

ON MY CJ 5 THE ROCKER PIVOTS BOTTOM OUT ON THE ON THE TOWER IN WHICH THE STUD SCREWS INTO. WHEN THE BOLTS ARE PROPERLY TIGHTENED (OR EVEN OVER-TIGHTENED) THE PIVOTS STOP IN THE SAME PLACE. THEREFORE THE ROCKER ARM'S HEIGHT IS NON-ADJUSTABLE. THE ONLY WAY TO ADJUST IS TO USE LONGER OR SHORTER PUSH RODS

THE DEPTH IN WHICH THE PUSH ROD "SINKS" INTO A PUSH ROD IS IMPORTANT.

A STUPID EXAMPLE IS AS FOLLOWS:

THE TAPPET IS DRY AND FULL TRAVEL OF THE "SPRINGY" PORTION (MEASURED WITH A DIAL INDICATOR) IS 3/16 (.0375)

THE CAM LOBE IS DOWN AND 180 DEGREES FROM LIFTING THE LOBE (SO WE'LL SAY THE LIFTER IS "BOTTOMED OUT")

WHAT WE THEORETICALLY WANT IS TO "PUSH DOWN INTO" THE "SPRINGY" LETS SAY 2/3s (OR.0258). THIS LEAVES 1/3 OF SPRINGY BELOW THE PUSH ROD

THE 2/3 YOU PUSHED DOWN----OVER THE LIFE OF THE ENGINE, WILL SLOWLY PUSH BACK UP, AS WEAR OCCURS --- THIS IS THE BEAUTY OF HAVING HYDRAULIC LIFTER--THEY ADJUST THEMSELVES, PROVIDED YOU THAT YOU SET THEM UP CORRECTLY INITIALLY

ON MINE--RIGHT LENGTH PUSH ROD, ON YOURS IT MAY BE HOW FAR YOU CRANK DOWN ON THE PIVOT, THAT'S WHY I WANT TO SEE SOME GOOD PICS, WHEREAS I CAN SEE THE SET UP.I'M A JEEP CJ KINDA GUY AND I UNDERSTAND HOW THIS STUFF WORKS---I JUST DON'T KNOW YOUR ENGINE!

ON MY JEEP--ONCE THE TAPPETS FILL WITH OIL--THERE IS NO LONGER ANY SPRINGY, THEY FEEL SOLID

IF I INSTALL A REPLACEMENT PUSH ROD FOR SOME REASON (THE SAME LENGTH I WAS USING), THE 1ST TIME OR TWO THE ENGINE ROTATES, MY VALVE WILL BE SORTA "CRACKED OPEN". UNTIL I GET OIL PRESSURE

HOWEVER WHEN IT THE TAPPET DROPS BACK INTO THE PRESSURIZED OIL GALLEY. IT WILL "UNLOCK" AND ALLOW THE PUSH ROD TO DROP BACK INTO THE NORMAL 2/3 OF THE WAY DOWN POSITION.

THESE THINGS UNLOCK AND READJUST EVERY TIME THE DROP DOWN!

IT WILL THEN OPERATE NORMALLY. PUSHING UP A "BILLIONTH OF AN INCH" AT A TIME, THUS REMOVING SLACK FROM THE SYSTEM ALL OF THE TIME.

HERE'S THE KICKER!

ADJUSTED TOO DEEP, THE VALVE WILL NEVER CLOSE COMPLETELY

ADJUSTED TOO SHALLOW, YOU DON'T HAVE ENOUGH "OVER THE YEARS" AUTOMATIC SLACK ADJUSTMENT

ADJUSTED WAY TOO SHALLOW, YOU WILL HAVE WAY TOO MUSH SLACK, AND THE VALVE TRAIN WILL "TAP" AND "RATTLE" CONSTANTLY

DID YOU HAVE ANY CLUE THIS WAS THIS COMPLICATED?

THE MEDIC
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Sunday, May 20th, 2012 AT 1:19 PM

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