Author Topic: Rocker shaft orientation  (Read 3805 times)

Offline shadango

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Rocker shaft orientation
« on: June 04, 2014 - 10:56:23 AM »
Just about to button up the right side while doing the new springs and I found yet another screw up on the part of the previous builder....maybe.

The manual for the engine says "Install rocker arm and shaft assemblies with "NOTCH" on end of rockershaft pointing to centerline of engine and toward front of engone on left bank and to the rear on right bank."

The shaft on the right side right now has the "groove toward centerline but to the front of the engine (just like the left side). That is how it has been running.

Trying to decide if I should leave as is or switch.     On one hand, the engine has been running like this for some time and seemingly OK........on the other hand it is "wrong"....but the shafts and rockers are already worn with this configuration. So I am thinking I could do more harm than good switching it now.

Any thoughts?  :popcorn: :clueless:




Offline shadango

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Re: Rocker shaft orientation
« Reply #1 on: June 04, 2014 - 11:08:10 AM »
Looking at the shaft, the oiling holes for each rocker are toward the "top" of the centerline of the rocker arm versus on the "bottom" of the centerline if i were to reorient it.....

Offline Strawdawg

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Re: Rocker shaft orientation
« Reply #2 on: June 04, 2014 - 11:46:14 AM »
In order for oil to get into the rocker shaft, the shaft has to be installed as per the shop manual's instructions because there is only one feed on each bank...seems to me that you would have  a dry side if the shaft was installed wrong???

Offline shadango

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Re: Rocker shaft orientation
« Reply #3 on: June 04, 2014 - 12:06:11 PM »
I just started it up and pulled the rocker covers....all rockers have oil......

One concern I have though is I seem to have more rocker noise than before......

Would that be normal with all new springs? 

(I double checked the bolts for the shafts and all seems well......   

***Update:   No worries.....guess teh shafts had to fill up with oil...probably should have prefilled them i guess?   All seems fine now. Ran it up to normal op temp and is now cooling.
« Last Edit: June 04, 2014 - 01:27:06 PM by shadango »

Offline Strawdawg

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Re: Rocker shaft orientation
« Reply #4 on: June 04, 2014 - 02:12:53 PM »
sounds good :)

So are they installed as per the factory, or the way they were?

Offline shadango

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Re: Rocker shaft orientation
« Reply #5 on: June 04, 2014 - 02:43:31 PM »
sounds good :)

So are they installed as per the factory, or the way they were?

I have the right side still installed as they were .....the "notch" toward the front and toward centerline versus what the manual says, with the notch to the back.

I examined it and it seems like as it is, the oiling holes in the shaft end up ABOVE the "centerline" of the shaft this way, versus "below" it....seems like it will still do its job, although I wonder if the oil ports are supposed to be BELOW the centerline for full flow maybe?  I didnt look at the left side...just installed with notch to the front and centerline as it came off.

I was thinking of changing the orientation of the right shaft but that would mean that the rockers would switch positions and "direction" on the shaft.....and not sure if that would be ok or not?

Offline Strawdawg

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Re: Rocker shaft orientation
« Reply #6 on: June 04, 2014 - 03:18:07 PM »
I don't have one to look at, but I understand the small holes in the shaft should point down and toward the exhaust ports....If I understand you correctly, yours are pointing upward?  :)

With the holes, or the grooves, on the bottom, the oil is delivered to the area of maximum wear.....when they are on top, they are not...I would install as per the book after looking at my manual

Be sure the rockers are offset in the correct direction as well...the guy that put the engine together may have been related to me :D
« Last Edit: June 04, 2014 - 03:48:40 PM by Strawdawg »

Offline RzeroB

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Re: Rocker shaft orientation
« Reply #7 on: June 04, 2014 - 08:05:50 PM »
I don't remember which way the "notches" on the end of the rocker shafts go. I do know that the small oiling holes drilled in the rocker shaft approx 15 degrees offset from the rocker shaft hold down bolt holes should be pointed down and with the 15 degree offset to the valve side of the rocker shaft.
Cheers!
Tom
St Louis, MO

Former owner of 16 classic Mopars. "It is better to have owned (Mopars) and lost then to have never owned at all" (apologies to Alfred Lord Tennyson)

Offline Strawdawg

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Re: Rocker shaft orientation
« Reply #8 on: June 04, 2014 - 10:07:07 PM »
Looking at the manual, it's simple.  Leaning over the fender, the notches go toward your left hand.  Holes go down so that oil is released into the bottom of the rocker saddle.  This is important because this is the load bearing part of the rocker where most of the wear will occur.  There is a picture in the oil circulation section showing the relationship of the rocker shaft oil feed hole to the rocker....but basically, the holes go down.

As I said prior, be sure, when you orient the shaft properly, that the the rocker offset is correct as shown in the manual.  In my head, I cannot decide if this offset is affected by reversing and rotating the shaft :)

I would definitely install it correctly to avoid rapid wear of the rocker and shaft.

Offline shadango

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Re: Rocker shaft orientation
« Reply #9 on: June 05, 2014 - 12:05:21 AM »
Thanks guys.

The concern I have is that at this point the engine has been run for at least 15k miles that I have had it plus another 15k or so prior to me (guessing) this way.......wear patterns etc have set in as it is now.  Installing the correct way at this point could cause more wear than leaving it, couldn't it?

I have examined things closely and to the eye and fingers at least the shafts/rockers seem no worse for wear compared to the other side......and oil still flows into the rockers....... :dunno:

From what I can figure, the offset of the rockers are not affected....I didnt measure it, but the distances look the same.....

Offline Strawdawg

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Re: Rocker shaft orientation
« Reply #10 on: June 05, 2014 - 09:01:14 AM »
the majority of the wear will be on the bottom of the shaft and that is where you want the most oil to minimize it.  I would definitely install it properly.  If you are concerned, you can buy a new shaft as they are not that expensive.

I just could not visualize the right and left rockers in my mind to see if they were still "right" and "left" in orientation after flipping the shaft end to end :)

Offline shadango

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Re: Rocker shaft orientation
« Reply #11 on: June 05, 2014 - 12:38:41 PM »
the majority of the wear will be on the bottom of the shaft and that is where you want the most oil to minimize it.  I would definitely install it properly.  If you are concerned, you can buy a new shaft as they are not that expensive.

I just could not visualize the right and left rockers in my mind to see if they were still "right" and "left" in orientation after flipping the shaft end to end :)
Makes sense.  I switched it around.  Saw no odd wear really on the shafts so I guess it will be fine.

Offline Strawdawg

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Re: Rocker shaft orientation
« Reply #12 on: June 05, 2014 - 01:19:02 PM »
Higher rpm and/or stiff valve springs will make the wear worse.  I am sure yours will be fine now.  Strange how many things we find when we start looking at others work...and sometimes, my own!