• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Rocker arms STILL loose!!!!

  • Thread starter Thread starter donsbad68
  • Start date Start date Nov 5, 2004

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 5, 2004
#1
  • Nov 5, 2004
  • #1
OK, Mr. Yount (sic) and many others have already told me to run the rocker arms in order and to try to pump them up by cranking the car with the coil wire off. I did so and checked after I pumped up about 20 lbs of pressure on the gauge and held it there for about 30 sec or so..... took off the valve cover......all are still loose except for the ones with the valves open of course. This is getting fairly upsetting. Do I need longer pushrods or what?? There is about to be an 89 lx with a non-running new 306 on the market!!
 

jwzg

Member
Apr 6, 2004
237
0
16
Prattville, AL
Nov 6, 2004
#2
  • Nov 6, 2004
  • #2
What procedure did you follow exactly?
 
R

Ray@VSK

New Member
Aug 27, 2004
355
0
0
Nov 6, 2004
#3
  • Nov 6, 2004
  • #3
Don't turn it over using the key, put a 1/2 rachet on the crank & turn it slowly doing em 2 rockers @ a time using someone watching & holding the rods down as you turn it "by hand" if your worried the bolts are backing out put allittle thread sealant or gasket sealer on the bolts prior or it be worse, it could be your cam, sure you don't got to stiff of valve springs on it.
 

onefaststang

Kingpin
Founding Member
Jan 1, 1999
9,049
4
79
Elmira NY
Nov 6, 2004
#4
  • Nov 6, 2004
  • #4
stud mount or pedastal mount rockers?
What heads, have they been milled?
 

jeffnoel

Founding Member
Aug 31, 2002
1,638
5
37
Clovis, CA
Nov 6, 2004
#5
  • Nov 6, 2004
  • #5
If there pedestal mount and you followed the correct procedure to preload them, then yes you need longer pushrods. Do you now how long the pushrods are that your currently using?
 

Starscream88

New Member
Mar 8, 2003
1,277
1
0
Park Ridge NJ
Nov 6, 2004
#6
  • Nov 6, 2004
  • #6
What heads are they?
I actually think its normal for rockers they have no load on them to be able to move from side to side slightly,

Your gonna have to tell us,
What heads,
What Cam
What rockers
What pushrods
Pedestal or Stud mount
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 6, 2004
#7
  • Nov 6, 2004
  • #7
the heads are stock e7te with just a valve job, the cam is an e303 the rockers and lifters and pushrods are all stock pieces.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 6, 2004
#8
  • Nov 6, 2004
  • #8
i did turn the crank by hand and follow the yount procedure when both where on their base circle, once this was done i cranked the motor to see if the lifters would pump up or anything.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 6, 2004
#9
  • Nov 6, 2004
  • #9
p.s. they did not tighten up at all.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 6, 2004
#10
  • Nov 6, 2004
  • #10
Describe in more detail the EXACT procedure you went through to install the rockers. And that cam with stock heads/springs isn't gonna be much fun.

You don't have to prime/fill the lifters to properly install the rockers, although I suppose it won't hurt.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
Nov 7, 2004
#11
  • Nov 7, 2004
  • #11
I installed mine correctly (stud mount) and then spun the oil pump with a drill, but the lifters did not pump up all the way - that didn't happen until the engine was running for a minute or two, then the valve train ran wisper quiet.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 8, 2004
#12
  • Nov 8, 2004
  • #12
The procedure as given by Mr. Yount.

Be sure the pair you're installing have the lifters on the base circle of the cam - in other words, both valves would be closed if the rockers were on. Hand tighten them to zero lash - with one hand rock the rocker while tightening with the other hand. Once it barely stops rocking (no gap on the pushrod end or the valve stem end) you've reached zero lash. From that point, torque to 18-20 ft-lbs while counting the number of times the bolt turns. It should reach that torque somewhere between 1/4 turn and 1 turn. If it takes more than 1 turn to hit the torque when starting from zero lash, then shim the rocker higher. One .030" shim will reduce the number of turns by about 1/4. If it hits the torque in less than 1/4 turn - you'll likely have a hard time getting it to zero lash by hand, or to zero lash at all - you'll likely need longer pushrods. If it hits the torque just short of a 1/4 turn, you may be able to 'shorten' the rocker by evenly removing some material from the bottom of that rocker's fulcrum. Unless you've replaced the cam with a different one (sometimes replacement's have a slightly smaller base circle) you probably won't run into needing new pushrods.

Once you've installed each pair this way (you'll have to turn the motor over by hand to get each pair of lifters on the cam's base circle - follow the firing order to minimize hand cranking) and cranked the car, if they're noisy, you may have to go back through with everything good and hot (or at least warm) and re-install. The clearances change slightly when things are warm, and I've found that any noisy ones I've had generally quiet down when I do the install procedure warm.

Note that the rockers aren't really adjustable. The install procedure is there to tell you if things are dimensionally the way the should be in the engine. You can just torque them down - but then you won't find out about any potential dimensional issues until you crank it. And then, occasionally, you can find out about them the hard way.

P.S. why wont the cam be fun? I have gt-40 intake and a few other pieces will it not give me power over stock?
 

84blkstang

Member
Jun 4, 2003
544
1
18
Springfield MO
Nov 8, 2004
#13
  • Nov 8, 2004
  • #13
If these are stock pieces, i had the same problem. We went along and tightened up all of the rocker arms but they were still loose and we thought that the lifters would pump up. Well it didnt work, my machinest told me why. When you take an old head in the valves are recessed in the head from wear, and when this happens your rocker arm takes up the slack, wearing in the middle, and when When you have a valve job done it takes the valve back to stock height. Therefore creating a lose rocker arm. I had to buy new ones. It fixed my problem, i thought that this would help you somehow hopefully thsi makes sense
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 8, 2004
#14
  • Nov 8, 2004
  • #14
donsbad - the designer of that cam is Crane; it's identical to Crane's PowerMax 2040. Here's what they recommend to go along with the cam:

"GOOD MID-RANGE AND STRONG TOP-END POWER, REQUIRES MODIFIED MASS AIRFLOW, AFTERMARKET INTAKE, PERF. CYLINDER HEADS AND HEADERS, MUST USE 5-SPD AND 3.55 OR NUMERICALLY HIGHER REAR GEARS. REQUIRES CRANE SPRINGS AND RETAINERS. (50 STATE LEGAL 85-93, C.A.R.B. E.O. D-225-46) BASIC RPM 2400-6000"

If the valve springs are stock, many people experience valve float in the 4500-5000 rpm range due to the extra lift of the cam. The stock springs weren't designed to handle that. Also, while you might gain a few HP at peak if you have the valve springs to let you rev high enough to get to it, the bottom end torque production of the engine will likely be much softer - the engine usually feels quite lifeless below 2500 rpm. This makes for a street car that's not much fun to drive. The intake will help; not sure about the cam. Good luck with it.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 8, 2004
#15
  • Nov 8, 2004
  • #15
should i get new rocker arms and pushrods and put the stock cam back in? Do i need new lifters too? I just want this thing to run now. Forget the power aspect.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 8, 2004
#16
  • Nov 8, 2004
  • #16
ttt still need an answer on how to make this piece of poop run.
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 8, 2004
#17
  • Nov 8, 2004
  • #17
is there no-one?
 

donsbad68

Immensely Educated
Jan 4, 2003
838
0
0
Oklahoma
Nov 8, 2004
#18
  • Nov 8, 2004
  • #18
ttt
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
Nov 9, 2004
#19
  • Nov 9, 2004
  • #19
Sounds like you have rocker or pushrod issues. I don't know that you know if the rebuilder set valvve stem height back to stock specs - that would afffect valve train geometry as mentioned. I don't know that there is any more advice that we can give. If you can't get any pre-load on the lifter with no shims in the pedestals, then you need to consider buying a $16 adjustable push rod to check what length pushrod you need.
 
You must log in or register to reply here.

Similar threads

C
Valve stem tip tap?
  • Coolen
  • Apr 6, 2025
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
20
Views
872
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Apr 14, 2025
Noobz347
6
Hey all,I’m putting together a 302 for my 1968 Mustang and wanted to post the combo + some questions to make sure I’m not missing crucial
  • 68_Disgustang
  • Feb 22, 2026
  • 1965 - 1973 Classic Mustangs -General/Talk-
Replies
4
Views
871
1965 - 1973 Classic Mustangs -General/Talk- Jun 20, 2026
gray owl
G
Y
Engine Oily cylinder- bad lifter relationship
  • Yoyoda
  • Nov 9, 2024
  • Fox 5.0 Mustang Tech
Replies
3
Views
463
Fox 5.0 Mustang Tech Nov 16, 2024
Yoyoda
Y
Drivetrain 83’ Glx convertible C5 Trans help!
  • JacksonJared2113
  • Dec 25, 2025
  • Fox 5.0 Mustang Tech
Replies
2
Views
387
Fox 5.0 Mustang Tech Dec 26, 2025
JacksonJared2113
S
Fuel Spits sputter pops and bangs under load. Help wanted
  • sickntired
  • Mar 23, 2024
  • Fox 5.0 Mustang Tech
  • 2
Replies
22
Views
3K
Fox 5.0 Mustang Tech Apr 1, 2024
sickntired
S
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?