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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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1.7 Cobra Rockers, should i use shims?

  • Thread starter Thread starter Kdubslugga
  • Start date Start date Feb 1, 2006

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Feb 1, 2006
#1
  • Feb 1, 2006
  • #1
Am i supposed to use shims or is it ok not to, i got some Ford Racing Pushrods, just stock replacements
 

352Ford2

New Member
Oct 12, 2005
393
0
0
Seattle,WA
Feb 1, 2006
#2
  • Feb 1, 2006
  • #2
only use shims if you need them. It is ver important to go through the check procedure after installing rocker arms, I listed the link below.

http://static.summitracing.com/global/images/instructions/fms-m-6564-a351.pdf

bottom of page 2
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Feb 2, 2006
#3
  • Feb 2, 2006
  • #3
Thanks for that link, came in handy. I checked on a few of the rockers to see how much the fulcrum bolt turns and its about 3/4 a turn before it reachs 18-20 ft lbs of torque. However i do a a small question, on cylinders 4 5 6 and 8 a few of the rockers just keep on tightening compressing the valve springs, im assuming this has something to to with the firing order or something, now when i rotate the engine and tighten everything down under Top Dead Center this wont happen right? No Rockers should be compressing the springs right?
 

Stormwalker

Not a New Member
Nov 19, 2003
83
0
8
Ft Ripley, MN
Feb 2, 2006
#4
  • Feb 2, 2006
  • #4
Kdubslugga said:
Thanks for that link, came in handy. I checked on a few of the rockers to see how much the fulcrum bolt turns and its about 3/4 a turn before it reachs 18-20 ft lbs of torque. However i do a a small question, on cylinders 4 5 6 and 8 a few of the rockers just keep on tightening compressing the valve springs, im assuming this has something to to with the firing order or something, now when i rotate the engine and tighten everything down under Top Dead Center this wont happen right? No Rockers should be compressing the springs right?
Click to expand...

I believe you should have the cylinder at tdc on the compression stroke for the rockers you are doing. That way, the lifters are "all the way down". That's the condition it should be to tighten it to 18-20 ft lbs. Easiest to do it in the same order as the firing order I believe.
You can also check your pushrods by hand for play and such, assuming you have your lower intake off.
 
8

8950HO

New Member
Mar 31, 2005
658
2
0
Feb 2, 2006
#5
  • Feb 2, 2006
  • #5
Kdubslugga said:
Thanks for that link, came in handy. I checked on a few of the rockers to see how much the fulcrum bolt turns and its about 3/4 a turn before it reachs 18-20 ft lbs of torque. However i do a a small question, on cylinders 4 5 6 and 8 a few of the rockers just keep on tightening compressing the valve springs, im assuming this has something to to with the firing order or something, now when i rotate the engine and tighten everything down under Top Dead Center this wont happen right? No Rockers should be compressing the springs right?
Click to expand...

Make sure the valves that the rockers are compressing the springs on are closed.I just work on one cylinder at a time.

You may have some defective lifters.I ran into this problem myself when I installed those rockers.
One lifter would not bleed down at all,(with valve closed).Tightening the rocker would open the valve.I replaced this lifter and it was fine.

But first make sure the lifter is on the base circle of the cam lobe and the valve is fully closed first.

The rocker should not open the valve if the valve is fully closed and the lifter is off the cam lobe.
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Feb 2, 2006
#6
  • Feb 2, 2006
  • #6
So it would be normal for the rocker to compress the valve spring if i tighened it while the lifters were not seated at the bottom? I can clearly see the pushrods are sitting a bit higher on the rockers that are compressing the valve springs, so if i rotate the crank and tighten everything down in order the rockers should absolutley not compress any valve springs right?
 

352Ford2

New Member
Oct 12, 2005
393
0
0
Seattle,WA
Feb 2, 2006
#7
  • Feb 2, 2006
  • #7
Kdubslugga said:
So it would be normal for the rocker to compress the valve spring if i tighened it while the lifters were not seated at the bottom? I can clearly see the pushrods are sitting a bit higher on the rockers that are compressing the valve springs, so if i rotate the crank and tighten everything down in order the rockers should absolutley not compress any valve springs right?
Click to expand...


You need to be at TDC of the comp stroke of the cylner you are working on, that should fix these issues
 
M

matm347

Founding Member
Aug 29, 2000
2,056
0
0
Feb 2, 2006
#8
  • Feb 2, 2006
  • #8
Yes, what you are seeing is normal, just do as stated above and rotate the crank until the lifter is on the base circle. Use shims only as needed. They come in two different sizes...two thin ones are usually equal to one thicker.
 

Zero_chance

Founding Member
May 29, 2001
1,244
7
59
Maricopa, AZ
Feb 2, 2006
#9
  • Feb 2, 2006
  • #9
Thats a pretty handy link for anyone doing rockers.
 

Kdubslugga

Active Member
Jun 7, 2003
1,515
3
38
Akron, OH
Feb 2, 2006
#10
  • Feb 2, 2006
  • #10
Awesome guys, thanks a million!!
 
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