[mbeeman400]

Read quite a few threads here, know it's been discussed.
I have 70 TA, 400 RA lll with 12X heads. Need to adjust lash on ticking valves.
First attempt using some 3/8" locking nuts with a thick hardened washer resulted in louder ticking.
So thinking of removing the 50 year old parts and going to new
7/16" over 7/16" ARP studs,
Elgin SS 1.5 Rockers
Need to keep stock valve covers
To see if I can get the correct pre-load to quiet the valve train down.
I see several recommendations for rocker arms and rocker arm studs
Somewhat confused on different lengths of studs
As always, thanks in advance for any help or comments! Mark

[lust4speed]

First off insure that you pick a valve adjusting method and set them all properly. Forum members are split on the best method, but since this is my post I will share my favorite with you. First off remember that the engine turns clockwise when viewing it from the front of the car. I start with #1 cylinder with the exhaust rocker just starting to rise and I then set #1 intake for a half turn after zero preload, and then continue down the firing order until all the intakes are done. Then come back to #1 and have the intake rocker go up and almost all the way back down and then adjust #1 exhaust. It is pretty much a no brainer and goes smoothly. With any method the most important thing is finding zero lash and I find that spinning the pushrod doesn't work well for me and sliding the top of the pushrod back and forth in the pushrod cup is much easier to feel when the slack is just taken up. Moving the pushrod across the rocker cup from the passenger to driver sides works better than front to back.

Once you get all the valves adjusted take a look at all the nuts and see if they are about the same distance down from the top of the stud. If any are noticeably higher or lower you either missed adjusting those or worse the cam lobe has wear and more adjustment was needed to get back to the proper preload.

[shoebox1.1]

I do one cyl at a time starting with no.1. Same thing, watch exh rocker just as it starts to open set no.1 intake. Then rotate engine around and as intake rocker is fully open the. Set the exhaust

[steve25]

I would first off confirm that the Cam lobe and lifters working on any noisy valves are good, if not you can adjust until the Cows come home with no effect!

You need to confirm that the push Rods are spinning.
Every time a valve opens and closes the push rod will spin once if things are well.

Pull a valve cover with the motor warm, wipe the oil off a top of a push rod side and mark it with paint.

Then stuff a long strip of tall enough cardboard to extend above rocker arm height down along the space between the valve springs and the Exh port side of the head which would have been under the valve cover and look to see when the motor is running if those noisy rockers have spinning push Rods.

[Cliff R]

If some pre-load is established and you have "ticking" then the problem is with worn parts more than how they are adjusted. In theory it really shouldn't matter where the plungers are located in the lifters as far as noise is concerned a the close tolerance between the plunger and lifter body makes it act like a solid lifter on the upstroke.

This simply happens because the leak down rate with most lifters (unless you purchased a "fast-bleed" variety) is pretty slow, usually around 120 seconds. When we get excessive noise from the valve train and the lifters have preload then you either have a bad cam lobe, worn lifter, defective check valve in the plunger, worn rocker arms, worn valve guides, worn lifter bores (rare), or combination of wear in multiple places allowing unreasonable amounts of movement between the parts where the lifters are not able to establish and maintain zero lash thru their range of operation. I small piece of dirt/debris stuck in a lifter can also cause excessive noise and nothing excessively worn anywhere else.

Of course all of this assumes that the lifters are good parts. In recent years we've seen a LOT of defective lifters right out of the box. This started about 15 or so years ago when the USA companies started having troubles staying in business and keeping up with demand. Of course the quick fix was to go to Mexico and offshore for lifters which pretty much turned the industry upside down as we started seeing all sorts of noise issues and lifter/lobe failures as a result.

Prior to this happening dating clear back to my first engine builds in the mid-1970's it was rare as a winning lottery ticket to even hear of or have a lobe/lifter failure with any of these engines. Folks immediately started blaming lack of trace elements in the lube oil, incorrect "break-in" procedures, not removing inner springs, etc, etc.

Personally I just think that the market got flooded with "soft" lifters that were poorly machined and "soft" materials, so all the drama started and is still happening today.

I got lucky here because we switched to roller cams way back in 2004 and the few flat cam engines I've done got Rhoads lifters which are built using USA Johnson lifters as a starting point.

Another contributing factor seldom discussed or mentioned as contributing to lobe failures are faster ramp camshafts and using much stronger spring loads to keep things in check. I suppose all of it adds up to what we've been seeing now for the past 15 years or so. I'm not even sure about the cam cores or if some of these manufactures even went off-shore for those parts, but it wouldn't surprise me as out-sourcing keeps costs down and helps companies be competitive for price and increase profit margins.

The customers are also their own worst enemies with these things. I don't care what folks say in public Forum or sitting at a car show in these discussions, Googling up the absolute LOWEST price with free-shipping gets the sale more times than not. So when folks are sourcing out engine parts, and they type in flat cam/lifters into the Search line, they are going to buy $34 lifters vs $100-150 just about every single time. A few months later when they start getting excessive lifter noise from their new engine, and discover a few "scrubbed" lobes, they woln't remember the $80-100 they saved buying the cheapest possible parts out there.

Sorry to get a little off-topic, but cost drives this industry, and outsourcing parts has flooded these markets with substandard components.

Hey, I even got "hosed" with my current engine. I bought the cam/lifters and stainless steel full roller rockers as a "package". The rockers looked like Crower clones and very well made so I never gave it a second thought. Not long after the engine was placed in service I started getting excessive valve train noise and after several attempts to quiet things down were unsuccessful a closer look at things revealed that the rollers were grinding up the pins going thru them. The play on some by the time I got them out of my engine was over .015"! I would not have discovered this early in the game if I weren't running Crower HIPPO solid roller lifters and tight-lashing them. A hydraulic set-up would have continued to maintain zero lash with much less noise for much longer and put a butt-load more ground up metal into the assembly. So I dodged a bullet for the most part, and look much closer at EVERYTHING I buy and use in these engines.......FWIW.......Cliff

[KEN CROCIE]

If you couldn't get the valve train adjusted with a spacer washer and a self locking SBC crimp nut, (which us experienced Pontiac guys have been doing since the early 60s) , I suspect you have some other issues. Good advice from above forum participants for checking it out. Personally I suspect cupped lifters and/or a worn cam. The RA3 cam was the worst factory cam with regard to wear.

[STEELCITYFIREBIRD]

Some more info may help a logical desk diagnosis:

When the noise started...like after long storage or while in (regular continuous, seasonal?) service.
Sound narrowed to one, many variable, a single bank, or likely all valves?
Is it present only at idle, just off idle, or at 2k RPM plus too?
Any recent engine/other work, on this vehicle?
Possibly a little biographical info on the engine?


Luke

"First attempt using some 3/8" locking nuts with a thick hardened washer resulted in louder ticking."
This is an unexpected result but may be telling of the cause if accurate!

[Skip Fix]

Originally Posted by shoebox1.1

I do one cyl at a time starting with no.1. Same thing, watch exh rocker just as it starts to open set no.1 intake. Then rotate engine around and as intake rocker is fully open the. Set the exhaust

I do this so I don't forget to do a valve bouncing between cylinders. My ADD I guess

[steve25]

The best way to adjust them is with the engine running if you can deal with oil splash management.

Back off each adjustment until a very definded click can be heard, then make one and 1/2 full turn of the Poly lock, if you still have noise then you have problems adjustment will no resolve.