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Discussion Starter · #1 ·
When my motor is warm I hear noisy rocker arms, so last night I warmed up the motor and immediatley removed the valve cover, I couldn't budge some of the rockers however some moved around very freely with a lot of slop. I rotated the engine and some seemed to tighten up however some still seemed loose. SHould there be anymovement of the rockers after being adjusted. I have fully adjustable rail rockers (68MY) and when I installed the rockers I tightened the rockers until there was no up & down movement of the the pushrod to rocker and the piston on the lifter wasn't compressed at all. Once I reached that point I turned the nut 1/2 turn which moved the piston down in the lifter. After I fired the motor for the first time, the rockers seemd noisy so I adjusted each rocker an additional 1/4 turn (3/4 turn total). The noise at cold went away hoever when warm the nois is still there. Shall I go another 1/4 turn? All the books I read say to only go 1/2 to 3/4. What am I doing wrong? Also I have about 40psi of oil pressure at idle when warm, so I don't thing the lifters are collasping due to lack of oil pressure.

Thanks,
Dan
 

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warm up your engine to operating temp then reset your rockers by your manual. My quess is that the rockers and rail bolts are expanding due to heat and becoming loose. Only a thought.
 

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These aren't roller tipped rail rockers are they? If they are, you can adjust them 'till the cow come home, and they will NEVER be quiet.

When the engine is off, and the valves adjusted propperly, there will be lots of free play in all the rocker arms that are sitting atop of closed valves.

For fully adjustable rail rockers, I have an old valve cover with the center cut out of it. I put this on and adjust the valves with the engine running. The cut valve cover will catch 99% of all the splashing oil. You just loosen each rocker until you hear it tapping, tighten it JUST to the point that the tap goes away, and 1/2 turn past that.

I would not attempt to put a full turn past zero lash on the rockers. You'll most likely have some valves not fully closing.
 

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I am glad you mentioned the cut up vlave cover. The time I
tightened valves without it I spent the next two night cleaning the engine and exhaust..oil can spray all over can't it?
 

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Assuming you have a solid lift cam and lifters, you want to adjust the rockers after the intake ( right of the pair ) closes. Using a ratchet, rotate the crank clockwise till you see the left valve open/close then the right valve open/close. Once closed, go ahead and turn it about a 1/4 turn more on the crank, then adjust the lifters. On a typical solid cam, you want 0.024" of clearance between the valve and rocker arm. Use feeler gauges to get the setting right. It should be a tight fit getting the gauge in there, but it should be fairly easy to get the gauge in. Once it's set, slowly rotate the crank clockwise again using a ratchet for the next cylinder.

When done - MAKE SURE TO REMOVE THE RATCHET FROM THE CRANK!!! ;)

Someone else will have to give ya tips on hydraulic lifters. I haven't done them in a LONG while, and I used to set them while the car was idling < 1000rpm. ( squirting oil everywhere too - hehe ) I just laid a paper towel over the valves I wasn't working on to slow the spash, then adjusted the rocker till it stopped clicking.

I hope an expert chimes in
 

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Because of these quotes, I think it's safe to assume he as fully adjustable hydraulic lifters:
I have fully adjustable rail rockers (68MY) ... the piston on the lifter wasn't compressed at all ... I turned the nut 1/2 turn which moved the piston down in the lifter
 

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Maybe I'm misunderstanding, but it sounds like you adjust all your rockers at once, without rotating the engine. If so, that's your problem right there.

Also, I've never heard of a 302-2v with rail rockers. Am I missing something?

7
 

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Also, I've never heard of a 302-2v with rail rockers. Am I missing something?
As far as I know all '68 and '69 302's were rail rockers. I know that all 3 of my '69's have fully adjustable hydraulic lifters with rail rockers. Positive stop rockers came out in late '69, but IIRC, they were still rail rockers.
 

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Discussion Starter · #9 ·
Thanks for the info, I have some old valve covers at home, looks like I better cut off the top & adjust them like Johnpro reccomends. FYI I have a 68MY 302 stock rebuild with 260 comp cam, performer intake & Holley 465cfm vac sec.

Thanks again,

Dan
 

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You know what it is, I was confusing "shaft-mount" rockers with "rail" rockers.

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