valvetrain noise

For What Its Worth...

(Tech article provided by Ed Curtis of FlowTech Induction )


HYDRAULIC LIFTER/VALVE ADJUSTMENT PROCEDURE


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1. Remove the valve covers, and pick a cylinder you are going to set the pre-load on. Only do one cylinder at a time.

2. Rotate the engine in its normal direction of rotation (clockwise) and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder's intake rocker arm.

3. To adjust, back off the intake rocker arm adjusting nut and remove any tension from the push rod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the push rod seat up against the retaining lock, if you give it time to do so.

4. Twist the intake push rod with your fingers while tightening down the rocker arm. When you feel a slight resistance to the turning of the push rod, you are at "Zero Lash". Turn the adjusting nut down one half to three-quarters of a turn from that point for street applications. Use 1/8 to 1/4 turn for race applications. Lock the adjuster into position. The intake is now adjusted properly.

5. Continue to turn the engine, watching that same intake valve/rocker you just set. It will go to full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.

6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.

There may be some initial valvetrain noise when the engine is first fired up but once oil pressure has stabilized and the engine heats up, it should quiet right down to a normal level.

Remember that some racier camshafts will have a mechanical sound to them and will not be a silent as factory units.

first of all on Pedestal mount it does not matter 1/4 turn this 1/2 turn that......all you do is torque down the rocker bolt to specs and that is it. If they are too loose you need a longer pushrod and if they are too tight you need shims. The only way that i have found to really set them accurately is to take out the lifters and let them drain so therre is no oil in them, then when you adjust the rockers the lifter plunger will move up and down freely and you can see how much you are preloading the lifter and make the adjustments (shims or longer pushrods) FWIW i have Edelbrock heads with a Steeda#19 and ProForm Roller Rockers and my rockers are very noisy. I have triple checked the adjustment and when the valves are fully closed i can barely rotate the pushrod with my fingers...so they are maybe a couple of thousanths loose but i cant find shims that thin so i just live with it.

well to bring this back from the dead. I pulled mine v.covers off and I found 2 rockers that were loose, 1 on RH, and 1 on LH. So decided to add 1.6rr's and the rockers I bought were stud mount, so I also picked up the crane stud conversion kit. Ialso added new Lunati springs too. Pulled the old ones off and I could compress them with my hand. Gotta love coil bind from when I had the 274 XR grind Comp Cam in it. (565 lift) Went to tigthen the rockers down, and muthafreak me, they bottomed out before they were tight.. So purchase number 3, 6.500 Comp Chromemoly one piece pushrods (aka expensive) and now all my valvetrain noise is gone. It had gotten really loud and I was extrememly pissed, but now I actually enjoy driving my car again, especially when sitting in traffic. Plus it pulls damn near to the rev limiter a hundred times better than it did before and I can hear the cam a little more now

Tim

Glad you found the prob!

Later
Grady

same story here, I found crane cams tech site with some usefull info. on lifter pre-load,www.crane cams .com. Im going to follow there instructions and see if I can cure the valve train noise. I also have the #19 cam and went with 6.300 pushrods, and it diminished the noise but not all the way, this seems to be a common problem, good luck and let us know how you make out.

Check out FTIs site...he has a write-up on doing up the lifters....

Just in case some new folks to the 5.0 hobby are looking on I thought it might be helpful to add that rr's make a bit more noise than the stockers, even the ped mounts.

If using stud mount then the noise is usually more due to the guide plates.

JFYI

Later
Grady

I am too. I was almost to the point of just parking my heap, b/c it was embarrasing driving it around and sitting a stoplight having to listen to all that racket. But I love it now, all you hear is the faint chatter, and it sounds just like it is supposed. Plus I have the adjustability for future upgrades. I am ready to hit they dyno and see what it lay down now, I hope that my numbers come up quite a bit.

I'm reviving this....

I have Crane 1.7 pedestal mount RRs. NOISY is an understatement. . I ended up taking them back off tonight...

Combo: AFR 165 pedestal mount heads, stock rockers, stock cam and stock pushrods. Motor was quiet, quieter than it was with the stock heads as far as valvetrain noise goes... and idled and ran smooth as silk. Pulls clean & hard to the 5800 RPM limiter chip in the MSD box.

So today, I installled my Crane 1.7 RRs. I followed the instructions to a T. All the rockers tightened to the required 18 ft lb between 1/2 and 1 full turn. everything went really well. Fired the car, and a few of the lifters needed to pump at which point it quieted down enough for me to hear the chattery sound from the rockers. At this point is just sounded how I figured an aftermarket roller rocker sounded. Wasn't too serious.

Took the car out for a drive... drive around for about 15 mins then gave about 3 good WOT full 1/4 mile passes on a back road. Pulled over cracked the hood.. and notice the rockers are now louder at idle. Not much though.. drive back into town and as i'm driving I notice the rockers are getting louder and louder At 3000 RPM the chatter is so loud I could hear it over the radio... which was on fairly loud. Get home. I let the car idle in the driveway, and there's now a tapping sound coming from the pass side valve cover. You can hear it 10-15 feet away... hood open or closed.. just running. Also, when I was going WOT with it, anything more than 4500 RPM the roller rocker noise drowned out everything, even engine noise

I dont get it, I did everything by the instructions.. started with #1 then went to #2.. etc.. There doesnt appear to anything wrong with the rockers whatsoever. They look perfect.. no excessive play in them.. Are they supposed to just be THAT darn loud If so, I can't live with that kind of noise..... just gonna sell em and live with the .030" [or however much extra lift it is] less cam lift. Just a bummer caue I spent $320 CDN on them.

Make sure you don't have the bottom or the rocker and the top of the keeper touching. Even if they are close, under high rpm the amount of room will decrease.
I wanna say you need about 30 thousands of an inch but can't remember exactly.
Go to one of the big cam company sites and confirm.

Do you have the correct length pushrod to allow for correct valve train geometry?

I just saw you have ped rockers and with them you play around with shims as well as push rod length to get things right.

The roller should, for the most, part travel across the center of the valve tip if it is set up up correctly.

Later
Grady

Thanks!

Yes, the tops of the valves all have a wear mark thats basically right in the middle [like cutting a circle in half..?] from where the roller rockers were working the valve. I did check that right away when I yanked them back off.

At any rate, i'm just gonna leave the thing together with the stock rockers for this year. I have spent more time under the hood, or under the rear of the car, this season than I have driving it.. I can't be bothered to play with pushrod length and all that stuff at this point. It flies with the stock rockers on anyways and the motor is dead quiet.

I'm sure the rockers are fine... and it is a matter of getting different pushrods or something, I dont know. Just going to sell them, and the extra 10 or 20 HP I lose by not having them.... i'll just jet the nitrous kit that much higher... and done.

In seriousness I just wanna drive it for a month without having to pop the hood and add or change something.

I do understand about wanting to back off from the wrenching and start to enjoy some driving.

I would not worry too much about giving up all that HP cause IMHO the gain would be closer to 10 than 20.

Later
Grady