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Old 12-31-2015, 09:09 PM   #1
crossy
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Rocker arms are crooked?? virgin 350.

I have an engine on my run stand. It is an untouched , 1984 350 engine. It runs great, and has for all of it's 68,000 miles. I removed the valve cover and noticed a severe misalignment of the rocker arm to the tip of valve stem on 3 of the 8 cylinders. I knew the old 624 heads were pretty lousy, but were they known to have push rod guide holes too small, or way off center that much. The pushrods are the only thing that i can think of that would be pushing the rocker arm sideways. using the rocker stud as the fulcrum it would be easy for the pushrod to do that ,and i do see shiny, but unworn metal on the side of the pushrod. All 3 of the rockers that are mis- aligned have their valve stem end pushed to front of engine. I'm just curious. i thought about removing the intake (to contain chips), and grinding the pushrod hole bigger on that side. thanx, Crossy
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Old 12-31-2015, 09:26 PM   #2
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Re: Rocker arms are crooked?? virgin 350.

Should you worry about it? Nope.

It's 1955 technology.

There is enough meat on the rocker arm tip to still do its job, despite wild misalignment.

DO NOT grind the pushrod hole bigger, or the rocker will lose its controlling alignment. If it totally drives the OCD in you nuts, the best fix would be to have the heads machined for screw-in rocker studs with guideplates, at which point you have to drill the guide holes out large enough that they don't guide any more. Unless you're building something rowdy, totally not worth it.

But basically - fuggedaboutit. It will be fine.

(ps: '73 Pinto? Dude! Recovering Pintoholic here....)
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Old 01-01-2016, 09:40 AM   #3
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Re: Rocker arms are crooked?? virgin 350.

These rockers are a stamped steel and do fail .They wear and start to lean sideways . Over the years I have had 4 or 5 rockers fail . If it were me being you are already in it I would replace the rockers with new ones to remove the threat . Don't cost that much either . Also you could get a set of self aligning rockers if you wanted to up grade .

Also do not touch the guide hole . Thats the only thing that is keeping them straight . The push rod is supposed to touch .Gm uses this for alignment . If you open it up the push rod moves sideways and will make undesirable things happen .
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Old 01-01-2016, 12:39 PM   #4
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Re: Rocker arms are crooked?? virgin 350.

Stock valvetrain worn out in 64,000 miles? Must have been ridden hard and put away wet.
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Old 01-01-2016, 12:43 PM   #5
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Re: Rocker arms are crooked?? virgin 350.

If you do replace them I'd strongly consider going stamped or cast steel roller rockers. About $100 for a set from Summit. I don't know if there's any real disadvantage.
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Old 01-01-2016, 01:04 PM   #6
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Re: Rocker arms are crooked?? virgin 350.

Quote:
Originally Posted by slotard View Post
If you do replace them I'd strongly consider going stamped or cast steel roller rockers. About $100 for a set from Summit. I don't know if there's any real disadvantage.
Until the cheap needle bearing dies
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Old 01-01-2016, 02:56 PM   #7
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Re: Rocker arms are crooked?? virgin 350.

I've looked around and haven't found anyone who had one fail. I wouldn't be too concerned on a truck engine 350/383, if you were trying to build a real screamer of a 302 or 327 with a big cam turning fast I'd probably go for something higher end.
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Old 01-01-2016, 03:31 PM   #8
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Re: Rocker arms are crooked?? virgin 350.

For a daily I go with comps magnum tipped rockers. Stong body, roller tip, still uses the pivot ball like stock. Good peace of mind when using quality parts.
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Old 01-01-2016, 07:20 PM   #9
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Re: Rocker arms are crooked?? virgin 350.

Have you had it since new or taking some ones word it has 64,000?
A 30 yr old ENG with low mileage it could have a 164 grand would be more likely and still low mileage or is it a rebuilt 2 3 times.
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