My exessive noise in the valve train is because the sides of one of the self-aligning rocker tips is hitting the top part of the valve spring cap/retainer. Looks like only the exhaust valves spring tops are shaped in such a way to cause the problem, the intake tops are angled down so they don't have this problem.
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My question is, do they make different valve spring tops/retainers for self-aligning rockers or do I just have a messed up spring top?
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Looks like if I had non-self-aligning rockers I wouldn't have this problem because the self aligners look like this on the tip |_--_| where the valve stem would touch only the center indented portion, and non-self aligners look like this, |__| where only the roller tip would touch the valve stem.
Thanks

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Rob
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Are you still using factory retainers? If so, I'd get some new ones. Give me/us some more info on your valvetrain.

I wouldnt drive the car like that, if its pressing down on the retainer, theres a slight possibility a lock could make its way loose and find its way out, leaving the valve in the piston somewheres. It might be just fine but I certainly wouldnt trust it.

[This message has been edited by madmax (edited October 19, 2001).]

 

After further investigation, I've discovered that the rocker arm tip is moving drastically to one side as it depresses the spring. like about an 1/8 inch at the rocker tip.
This is the cause of the rocker tip touching the valve spring cap. I ground off the sides of a junk rocker, leaving only the part that depresses the valve stem and the sides that keep it aligned, and it still clacked loud, then discovered that the rocker tip is moving to the side as the spring is depressed, but the SPRING IS NOT moving to the side, so the valve is still straight.
The pushrod is straight and not bent either.
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These are World Casting Sportsman 200 heads, brand new, using 1.5 GM roller tip/bearing self-aligning rockers.
Should I have used aligning tabs and non-self-aligning rockers?
I'll post this as another question, thanks.

 

Remove the rocker and wipe all the oil from the valve stem tip. Use some Dykum Blue (or a Magic Marker) and color the tip of the valve.

Now install the rocker arm and adjust the lifter preload. Cycle the valve through one revolution. Remove the rocker and look at the mark where the lifter removed the coloration.

The line should be straight and in the middle of the valve stem tip. Also color should remain at the edges of the valve stem tip all the way around. If not, the rocker is riding too close to the edge of the valve. A different length pushrod should correct the problem.

Chances are you have a geometry problem.

Check that the underside of the rocker arm is not contacting the valve spring retainer.

Also check all of the components to make sure none are defective. Then buy a pushrod length checker and verify you're running the correct length pushrod.

You'll need to CLOSELY observe the roller tip of the rocker as is moves across the valve stem tip. With the lifter on the base circle, the roller tip should be slightly inboard (manifold side) of the valve stem tip. At mid lift, the roller should be centered on the valve stem tip and at max lift the roller should be toward the outboard side of the valve WITHOUT RIDING ALL THE WAY TO THE EDGE AT EITHER BASE CIRCLE OR MAX LIFT.

Aftermarket heads many times require a different length pushrod to give correct geometry, even when the head maker says the stock pushrods will work.

It's always better to run pushrods that are a little too long than ones that are a little too short.

Keep us posted.

Jake

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1986 Corvette Coupe, 415 CID, Edelbrock 6073s, ZZ9, TPIS Long Tube Headers and DynoMax Super Turbos (HATE 'em)

[This message has been edited by JakeJr (edited October 21, 2001).]

 

when i bought a used set of crane 1.6 RR
the arm was 'releived' close to the trunnion
of the rocker. apparently this is a common
cause, especially if using larger diameter
springs and retainers. looks like your needing
a geometry tool. plus an adjustable pushrod
tool.
update us with your findings.
airdeano

 

Looks like using the aligning tabs with a non-self-aligning rocker corrected the side to side movement problem, at least its not moving any more than any other valves now. The movement seems to depend on the position of the valve as it rotates slightly each time it is opened and closed, this seems to be the case with all of them.

[This message has been edited by 2QUIK6 (edited October 22, 2001).]