Rocker Shaft

Georgia200

Well-known member
I received my new rocker shaft today.

How tight should the pedestals fit on the shaft?

The rockers seem a bit loose, but I think I should hone the pedestals a bit because I really have to work to get them on the shaft.

That may be why one of them kept cracking. It might be binding on the shaft as I torque them down.
 
wondering the exact 1) product U purchased
&
ur 2&3) assembly/install method.
Knowing each may allow quality response...
 
Measure the OD in the unworn area of your old shaft & compare with the new shaft.
As you said you may have to hone the pedestals to be a slip fit on the new shaft.
If the rocker arms are loose, you will need new rocker arms. Go from there.
 
They are tightened to 30-35 ftlbs. That is from the 1965 Ford Shop Manual for Falcon, Mustang, Fairlane, and Comet. The huge red book.
 
What is your valve lash process? Zero push-rod lash is very light, and you can lash too far as the springs in the lifters do not have a lot of spring tension when not pumped up with oil. With the push rods at zero lash, the lifter will still collapse 1/4"-3/8".

Zero push rod lash, collapse lifter fully, set lash to 0.065-0.200"(shoot for middle) measured from valve stem to rocker tip.

Not knowing your knowledge level, and not assuming you are doing it wrong, valves have to be lashed at TDC on the combustion stroke for each cylinder, in the correct order of the firing order, or adjusted by Exhaust open, Intake close method.

If the pedestals do slide on, a tight fit would be better. Less deformation from extra space between the hole through the pedestal and the rocker shaft when torqued.

I'd try just heating them up with a hot air gun to expand them a little for assembly. Wouldn't torch the aluminum. Cold or warm work space?
 
I used oiled 400 wet sandpaper wrapped around a socket to hone the pedestals. I made sure there was a small amount of movement so the shaft didnt bind when I torqued them down.

A couple of the rockers should be replaced.

I used the procedure in the tech section to do an initial cold adjustment, then a warm adjustment.

There was some rocker noise after the cold adjustment and the valve train sounds pretty good after the warm adjustment.

A couple of teh adjusters are adjusted almost all the way down to get the proper lash,there is no more room for additional adjustments.

Here is where Im at:

The engine starts and idles smoothly. 18.5in of vacuum. Vacuum drops to 15-16in and holds when the power brakes are applied and held.

My 200 has the wrong balancer, the timing mark is way off, I think it is for a later 200. I set #1 at TDC and marked the balancer. When I started the engine and checked timing, it looked like 6 BTDC. I adjusted timing, idle mixture, idle speed, points to get the 18.5in of vacuum. Vacuum holds steady, timing mark holds steady.

So it should run like a champ, right?

As soon as I put it in gear, I hear a miss. I put new plugs in last week and the car was idled for about 20 minutes while I adjusted valves.

I pulled the plugs and they are as black as midnight. The first set I pulled right after I bought the car were black and soaked with fuel. These didnt have wet fuel but they look like I spray painted them black.

Compression was between 120-145, thats a bit low, is it low enough to foul plugs after 20 min of idle time?

Its rings or valve stem seals. Should I try and replace the valve stem seals without pulling the head, or should I just bite the bullet and pull the head?

Or, should I just yank the whole thing out and go from there?

On a positive note the rebuilt C4 operates flawlessly.
 
Id squirt some oil in the cylinders then recheck your compression. If it increases, rings are bad, if not its the valve seals. From there you will know which is the problem and then you can decide what to do. You can change the valve seals while its on the engine but you gotta have something hold the valve. Ive seen people hook up an air compressor and blow air into the cylinder in tye spark plug hole to hold the valve in place. Or jerry rig something.

Good luck
 
Georgia200":kmdd32am said:
I used oiled 400 wet sandpaper wrapped around a socket to hone the pedestals. I made sure there was a small amount of movement so the shaft didnt bind when I torqued them down.

A couple of the rockers should be replaced.

I used the procedure in the tech section to do an initial cold adjustment, then a warm adjustment.

There was some rocker noise after the cold adjustment and the valve train sounds pretty good after the warm adjustment.

A couple of teh adjusters are adjusted almost all the way down to get the proper lash,there is no more room for additional adjustments.

Here is where Im at:

The engine starts and idles smoothly. 18.5in of vacuum. Vacuum drops to 15-16in and holds when the power brakes are applied and held.

My 200 has the wrong balancer, the timing mark is way off, I think it is for a later 200. I set #1 at TDC and marked the balancer. When I started the engine and checked timing, it looked like 6 BTDC. I adjusted timing, idle mixture, idle speed, points to get the 18.5in of vacuum. Vacuum holds steady, timing mark holds steady.

So it should run like a champ, right?

As soon as I put it in gear, I hear a miss. I put new plugs in last week and the car was idled for about 20 minutes while I adjusted valves.

I pulled the plugs and they are as black as midnight. The first set I pulled right after I bought the car were black and soaked with fuel. These didnt have wet fuel but they look like I spray painted them black.

Compression was between 120-145, thats a bit low, is it low enough to foul plugs after 20 min of idle time?

Its rings or valve stem seals. Should I try and replace the valve stem seals without pulling the head, or should I just bite the bullet and pull the head?

Or, should I just yank the whole thing out and go from there?

On a positive note the rebuilt C4 operates flawlessly.

Those compression readings aren't all that low. If the plugs show signs of being fuel rich did you check the float level (wet fuel level) of the carb was correct? Did you retest your compression using a couple squirts of oil per cylinder to see if the compression goes up any? That would tell you if the rings are good or not. While the valve cover was off did you happen to look at the valve stem seals condistion? Old cracked valve seals are fairly easy to see and if that's the case Replacement of the valve stem seals with the head still on is easy I have done it many times over the years on many engines usally with good results. The exception is if the valve guides are also worn excessively, with the compression readings you have I wouldn't think that would be the case. Good luck (y) :nod:
 
I may B wrong but it appeared to me U were simplifying the plug reading operation.
Grab a vid or good article for more info:
https://www.tuningmatters.com/how-tos/b ... r-setting/
I have not read this 1 but there's plenty around (even on this site) that may go into great detail (a + benefit).
 
After a good long drive I pulled the plugs. They are looking much better, not quite the tan color I want, but much better than the last time I pulled them.

I still do not have the choke adjusted properly. The car will not come off fast idle unless I work the linkage manually. After it cools down from this last drive I will work on that issue. Im also not sure that I am getting full throttle when the pedal is floored. I will have to read up on throttle adjustment.

Its a process.
 
Georgia200":2hof1kri said:
Its a process.
Sure is, good luck w/it all.
Once U think U R closer (@ the end or 'done'),
have zeroed in on the correct heat range plug,
and R using it - do a "chop" read.
 
Georgia200":12ajv2gj said:
A couple of the adjusters are adjusted almost all the way down to get the proper lash,there is no more room for additional adjustments.

Seems like you have too much lifter pre-load OR worn cam lobes on those.
 
It's possible the outer ring on your harmonic balancer has slipped putting the timing mark out of index.

I had a 170 set at what read as about 35 degrees of initial timing by the marks, definitely slipped, but ran fine for years and never slipped more.

When you are compressing the lifters to set the lash, are there any lifters that don't seem to compress or compress less than other?

Possibly some failing or collapsed lifters?
 
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