Can't tell if I'm hearing lifter or rocker rattle.

[Black70c10]

So I've noticed over the last few weeks this rapid ticking noise coming from the passenger side valve cover, and I'm not sure if this is an issue with the lifter or the rocker arm..

Before we go any further, I tried to determine if I have hydraulic or solid lifters.. I used cylinder #8 to test, cranked by hand, watched the exhaust valve open and close, followed by intake valve open and close, and stopped once they evened back out and did not move with crank rotation meaning I'm on the compression stroke. I then tried to push down on the rocker (pushrod side) with all my force and there was no movement at all... Does this confirm solid lifters?

If so, and I pinpoint the one making the noise, does anyone have any suggestions as to determine if this is a lifter issue or maybe the rocker arm needs adjusting? I've read solid lifters need occasional adjustments. Thanks for the help

[hugger6933]

Solid lifters and solid roller lifters will need adjustment once in a while the later less so. If it is indeed solid it should have a valve lash of 26 or 28 thousandths, is a pretty common setting if I recall it has been a while since I was into that hot rod stuff. I would assume that you did not build the motor do you know who did? can you contact them to see if they might recall the cam type? Check the ones next to it and see if they have valve lash of mid twenty clearance or net lash meaning there is none on any of the rest. If none of the rest have any I would bet it is safe to say you have a hyd cam and need to adjust the lifter that has the loose rocker. On the same cyl bring the opposite valve up to open and just as it start to close then you can adjust the other valve. Loosen the set screw in the lock nut and turn the pushrod back and forth in a twirling motion in your fingers as you tighten the nut until it stops[that is zero lash]. Now tighten the nut another 3/4 to 1 and 1 1/4 round[3/4 has always worked wonderful for me] then tighten the locking screw inside the big nut and the noise should be gone if the lifter was out of adjustment, and from all indicators it sounds like it is. Jim

[airdale94]

If you get number 1 cyl. at TDC on compression stroke you can check/adjust these valves.

No 1 firing position - balancer at 0 deg
exhaust 1 3 4 8 intake 1 2 5 7

Number 6 cyl. TDC comp. stroke. (just rotate the eng. 360 degrees).
exhaust 2 5 6 7 intake 3 4 6 8

This is for hydraulic lifters.

[68gmsee]

All the lifters will make a clicking sound if you have solids since they should all have clearance as mentioned above otherwise engine would miss. Best technique to isolate the culprit is to run the engine and with a stethoscope or a 3 foot section of garden hose (my favorite) put one end to your ear and move the other end from rocker to rocker.

[Black70c10]

One other question for Hugger.. You said to check the clearances of the other rocker arms to get an idea of what the incorrectly lashed one should be.. Is there a right way to do this? Meaning, should I only check the clearances during compression or power stroke when both valves are closed?

[68gmsee]

My opinion is that it's very doubtful you have solids or they would all make a clicking sound when adjusted correctly.

If your engine is running smooth without missing and only one is clicking isolate the clicking one then try adjusting it as hydraulic lifter.

With rocker in the upper position or valve closed, loosen until you can barely wiggle the rod then tighten 1/2 to 3/4 turn. Shouldn't have to turn it anymore than that if your lifter is good. If it still clicks, then it's either a bad lifter, rocker or something else causing the noise.

One more comment: when hydraulic lifters are full of fluid you will not be able to push them down by hand. Also, unless they've been redesigned, with solid lifters there will be a slight up and down movement of the rocker due to the clearance adjustment.

[68gmsee]

And one last one: look at this video to get an idea of the adjustment procedure for solid lifters. This will give you an idea what hugger was referring to.

http://www.youtube.com/watch?v=3gMYWLMAzao

[Black70c10]

I appreciate all the feedback.

@hugger- no unfortunately the former seller hasn't responded to any of the my recent questions..so I'm pretty much on my own as to the cam specs unfortunately

@Airdale- thanks for the suggestions. You say this is applicable for hydraulic lifters, but do you think it's safe to assume I'm dealing with Solids? There was absolutely no downward give or movement when I attempted to press down on the pushrod side of the rocker arm.

#68gmsee- thanks for this suggestion. I'll definitely try this out once I feel confident I'm dealing with solids and ready to fix the problem..

[geezer#99]

I've heard that the pushrod cup on that style rocker can crack or loosen and create a ticking noise.

[myyamr7]

Find an old valve cover, cut the top off it, bolt it on, and set the valves (hydro lifters only) with the engine running. When i used to do this a lot, I got in the habit of tightening all the valves 1/4 turn before I started, usually took care of any stray clickers. Back the nut until the valve starts to click, slowly tighten it back up to the point it stops, then add 1/4 turn.
I just set the valves today on my 402...piece of cake other than the random squirt of oil.

https://www.youtube.com/watch?v=ifvP...ature=youtu.be

[Black70c10]

Ok, so I've identified the culprit. It's the intake valve on the #8 cylinder. Now, back to Huggers comments, you say to focus on the opposite valve which is the exhaust, and just as it begins to close, that's when I do my adjustment.

I just need clarification here because I'm watching a you tube video right now that says in this case, to make an adjustment on the intake valve, I need to wait until the exhaust begins to open...this is a little different.. Please help clarify for me.

On a side note, I assume that the set screws are difficult to open if you're not at the proper location on the cam, because I turned the crank until the #8 exhaust valve was just about to close and I couldn't loosen the set screw on the intake rocker to save my life... As far as I understand, you do not need to hold the nut in place with a wrench while doing this? I just cranked on the screw counter clockwise and got nothing.. Please help, I'm so close!

[Black70c10]

Just to expand, on this video they say the following:

Adjusting intake valve- adjust once the exhaust valve just begins to open. You're at the bottom of the cam shaft here.

Adjusting exhaust valve- adjust once the intake valve is fully open and just begins to close.

[custom1970]

Originally Posted by myyamr7

Find an old valve cover, cut the top off it, bolt it on, and set the valves (hydro lifters only) with the engine running. When i used to do this a lot, I got in the habit of tightening all the valves 1/4 turn before I started, usually took care of any stray clickers. Back the nut until the valve starts to click, slowly tighten it back up to the point it stops, then add 1/4 turn.
I just set the valves today on my 402...piece of cake other than the random squirt of oil.

https://www.youtube.com/watch?v=ifvP...ature=youtu.be

X2 always found this the best way. Can be a little messy though... I have little set of clips that you put over the rocker oil hole that work pretty good.

[GRX]

Originally Posted by custom1970

X2 always found this the best way. Can be a little messy though... I have little set of clips that you put over the rocker oil hole that work pretty good.

x3. Have a slotted valve cover for each of my engines.

[Black70c10]

@custom1970 & GRX- so you guys just tighten the nut and never mess with the locking screw? If so, are you both doing this while running? If that works I guess I'll give it a shot, just strange that others recommend adjusting both the locking screw and nut while the opposite valve is in a certain position.. Thanks for the input

[GRX]

Of course you tighten the locking screw, after the nut is adjusted. And they are called "posi locks".

[msgdsrf]

Tyically you do hold a wrench on the nut while turning the set screw, either direction. I have experienced very tight "locks" before and found that lossening had to be together and that give some relief to the set screw and can then seperate them. I have also found that the rocker stud will be the only thing to come loose and had to take the whole assembly to the bench to seperate the parts... it happens.

[msgdsrf]

When you tighten back down, have the set screw well backed off as not to interfer with your setting the lash (with the nut), then hold it in place with a wrench and tighten the set screw.

[Black70c10]

Thanks guys, I'll try adjusting the nut first and I'll also try adjusting them both in case they are locked up together.

So it sounds like there isn't too much of an opinion on when it's ok to adjust the intake valve..relative to the exhaust valve position..

[geezer#99]

Look at post # 3 here. Shows how to set them.
http://67-72chevytrucks.com/vboard/s...d.php?t=624297

[Ironangel]

Heres the method I just used... Valve Adjustment Procedure - The Quick and Accurate Way:
First, view this simple chart below for Small and Big Block Chevy Engines and see if you can understand it. There is more of an explanation below the chart. For other engines you will use the firing order that matches your engine to create a similar chart. This chart is based upon "opposite" cylinders of your firing order. (see below)

Intake Valve Adjustment: ENGINE OFF!

with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve


Exhaust Valve Adjustment: ENGINE OFF!

You will notice that this is the same procedure and sequence as the intake valves listed above. Only now you are adjusting ONLY the exhaust valves the same way.

with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve
http://www.centuryperformance.com/va...procedure.html

[Black70c10]

Thanks a lot, that looks like exactly what I need. Appreciate all the help guys. When I get home later, we'll see if I can just get the damn set screw loose

[Black70c10]

Well thanks for all the help, I definitely learned a thing or two. One of which being that I have a bad lifter, adjustments didn't help! Thanks for the tips, I'll know how to adjust them in the future.

[jhwkns]

Are You positive that it's not an exhaust leak?

[slow-1]

Originally Posted by jhwkns

Are You positive that it's not an exhaust leak?

Thats the first thing I thought of when I saw headers in the pic if the motor.

The other thought I had was a ground off cam lobe.