rocker shafts installed backwards... long read. but pics!

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KEVIN LANGFORD

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It seems my rocker shafts were installed backwards! Possibly when the engine was rebuilt in 2010.

I purchased my 71 Duster in 2017. New to Mopar's & learning. I have driven and worked on it since then approx 22k miles.
It was rebuilt in 2010 71 318la, bored .030 over, stock heads, comp cams Thumper camshaft, pushrods, springs. 340 intake, and a holley.
In 2021, I upgraded the top end w/ xheads, weiand stealth intake, a 650 proform carb. kept the pushrods and internals the same.
I disassembled and put it back together exact by pics and labeling everything.

I had a bit of timing chain strectch (approx. 12 degrees) develop because I drive the heck out of it!
I have torn into it and watched videos, explored forums to do the timing chain and double check internals with a scope. cleaning things up. etc.

I came across the rocker shaft discussion and mine are installed backwards.
So do I run them the way they have been?? Or take the shafts apart and install them correctly notched in the correct direction?

Its easy to do now and, I want to do it correctly!

Thanks for the input.

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Straight down photo would help immensely.
 
yes the rocker shafts are backwards. oops!

The rockers do align and the push rods do align as well

It has ran fine also. the push rods are hollow.. maybe that helped oil?
 
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I'd do it the right way. Shaft oiling holes point towards the exhaust manifolds when installed correctly.
 
It couldn't hurt it to take em off and swap just the shafts side to side. Lay some clean paper towels down to lay them on when you take them off. Lay them like they are oriented on the motor now, remove the bolts from the shafts and gently slide the shafts out while leaving the rocker arms laying in their positions. When you look at the bottom of the shafts, 2nd bolt hole back from the notch should be slightly bigger to allow oil up into the shaft where it will drip into the rocker arms to oil them. Yours have no doubt been oiling thru the pushrods, but being installed right can only help. The notch should always go down and to your left, not matter which side of the engine you're looking at. Just slide the shafts back thru the rockers that way on opposite sides you took em apart from and bolt em back down with the pushrods all lined up and you should be good to go.

:thumbsup:
 
I'll definitely swap the shafts to the correct direction.
I have time, I'm waiting on a timing cover from mancini anyway!
Thanks for the great feedback
 
While you have the shafts out swapping them, check the bottoms to see if they are worn. They really shouldn't be since they were getting oil. Unless the bottoms of the shafts and rockers are worn, I'd just put them back in right and send em! If your intake is still off, be sure to put thread sealer on the intake bolts when you put them back. Every one of them screw into the oil splash area below the rockers, and oil will wick back up the bolts and puddle up in your intake valleys if you don't seal them. :BangHead:

:thumbsup:
 
While you have the shafts out swapping them, check the bottoms to see if they are worn. They really shouldn't be since they were getting oil. Unless the bottoms of the shafts and rockers are worn, I'd just put them back in right and send em! If your intake is still off, be sure to put thread sealer on the intake bolts when you put them back. Every one of them screw into the oil splash area below the rockers, and oil will wick back up the bolts and puddle up in your intake valleys if you don't seal them. :BangHead:

:thumbsup:
I don't have the intake off currently and man I wish i would have sealed the threads I have two that leak a small teaspoon of oil every now and then. Maybe I can loosen slightly and get a small amount on the threads while its cold
 
Yup. Backwards. Notch on the passenger side down and to the rear, notch on the driver side down and to the front. The important thing is to make sure the small oiling holes point down and toward the valve springs, because sometimes, the shafts don't have notches or anything. It's all covered in the factory service manual. I highly recommend getting one.
 
It seems my rocker shafts were installed backwards! Possibly when the engine was rebuilt in 2010.

I purchased my 71 Duster in 2017. New to Mopar's & learning. I have driven and worked on it since then approx 22k miles.
It was rebuilt in 2010 71 318la, bored .030 over, stock heads, comp cams Thumper camshaft, pushrods, springs. 340 intake, and a holley.
In 2021, I upgraded the top end w/ xheads, weiand stealth intake, a 650 proform carb. kept the pushrods and internals the same.
I disassembled and put it back together exact by pics and labeling everything.

I had a bit of timing chain strectch (approx. 12 degrees) develop because I drive the heck out of it!
I have torn into it and watched videos, explored forums to do the timing chain and double check internals with a scope. cleaning things up. etc.

I came across the rocker shaft discussion and mine are installed backwards.
So do I run them the way they have been?? Or take the shafts apart and install them correctly notched in the correct direction?

Its easy to do now and, I want to do it correctly!

Thanks for the input.

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View attachment 1716243849

View attachment 1716243850

View attachment 1716243854
You want the oiling holes facing down towards the springs. Notch or no notch.
Not having them the right way will wear the rocker,shafts, stems more than necessary. Remember... of they were to point straight down.. yoy could put them on anyway ya wanted. They point down towards the springs.
 
Does the motor sound faintly (there's the headers) like a sewing machine??? Yes, get the oiling holes in the right place!
 
It seems my rocker shafts were installed backwards! Possibly when the engine was rebuilt in 2010.
I think I know the answer but I gotta ask. Did you check to see if the lifters are the AMC type? The kind of lifter that would oil through the pushrod?
 
For a mild engine like this, having the shafts upside down will have no long term problem. It just means on initial start up, the oil now has to fill the shafts to the top so that the oil can exit the shaft holes. This will happen veeeeery quickly as without the holes being at the bottom of the shafts, there is no leakage occurring & the shafts will fill quickly.
Drive & enjoy.
 
Frankly, I can’t believe this is a question.

It’s an easy thing to correct for zero dollars spent.
Why wouldn’t you want it right?
 
I found the exact problem with my engine after years of driving it. No idea who built this engine. It didn't cause any problems but I corrected it once I found it. Just check for any signs of wear damage that might cause issues.
 
before installing timing chain, soak it in a can of engine oil, for half a day, then install, it. chain will last longer. old motorcycle trick. just food for thought.
 
I think I know the answer but I gotta ask. Did you check to see if the lifters are the AMC type? The kind of lifter that would oil through the pushro

before installing timing chain, soak it in a can of engine oil, for half a day, then install, it. chain will last longer. old motorcycle trick. just food for thought.
I will do that! thanks for the tip!
 
I found the exact problem with my engine after years of driving it. No idea who built this engine. It didn't cause any problems but I corrected it once I found it. Just check for any signs of wear damage that might cause issues.
I used a camera bore scope to inspect things and I've rotated the engine to visually check for wear also.
I had some misfire at idle develop and that lead to this teardown. I've had the push rods out and check the lifters also.
The timing chain slack seems to be the issue. I could rotate it 10 degrees before the rotor began moving. rotating slowly to measure the play in the chain.
Ill be fixing the rocker shafts as I wait for parts.
 
I'll tell you this from DIRECT experience. IT MATTERS how the shafts are installed. Although yours are at least right side up, they're probably not hurt. BUT, years ago I was hurt on the job. At that same time I had to have an engine built. I always do my own, but then I had to hire a local "reputable" machine shop to build it. Just a mild 360 for a D100. They installed rocker shafts on both upside down and backwards. Also they just threw the rockers on randomly. Within 200 miles, the rockers and shafts were toast and squeaking and ticking like hell. With the oil holes pointing UP and not down, the rockers had no oil to ride on on the bottom where all the pressure is. Needless to say, I crossed that particular machine shop off my list.
 
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