Langadorf

Ever since I've reinstalled my recently ported heads I've been carefully listening to the motor as I drive it. Recently, I've been hearing this strange regular noise coming from the passenger side valve cover. It sounds like sort of a tick/clack kind of noise. I originally thought it was a loose valve lash, but I've reset all the valves twice and reset the passenger side valves yet again tonight. After I first started the motor up, I thought it had gone away, but after several seconds the noise came back. Also, on the passenger side exhaust I can see a very slight puff of white smoke coming out. The following are the steps I have taken to fix/identify the noise:

1) Reset all the valves (hydraulic roller cam CC306 w/ 1.6 RR) several times using the following method: First I make marks on the harmonic balancer 90* apart starting at TDC. I then watch the valves and rotate the crank until I see #1 intake valve closing then I continue to rotate it until the mark comes up to TDC. I loosen the locknuts and back off the larger nut. I then twirl the pushrod between my fingers as I tighten the large nut until I feel some resistance. Next I rotate the nut a full 180* clockwise. I then set the locknuts tight and tighten the whole thing about another 15-20* until it feels really snug. I do this for both valves then continue down the firing order until all the valves have been set.

2) I have listened all along the valve cover and on each header primary with a long torque wrench trying to identify exactly where the noise is coming from. However, I can't seem to pinpoint any one point that seems louder or that has a different sound.

3) I feared I might have a bad lifter rubbing on the cam wrong, so I changed the oil last night and looked in it for any metal flecks. I ran a very strong magnet all through the oil and didn't bring up any metal flecks at all.

4)Oil pressure seems to be good always around 40-60PSI. The car seems to idle and drive just fine. Tonight I wondered if maybe they weren't getting oil, but earlier today when I reset the valves on the passenger side, I had immediatly pulled the valve cover after running the car for 20-30 minutes at full operating temp (160 deg). There was oil puddles in each of the locknut holes and oil around the valvecover and rocker arms. I assumed this meant it was pumping oil. Also, if there was something rubbing wrong I would think the pushrods/rockers/etc would be VERY hot, but I was able to touch them long enough to set the valves w/out burning myself.

Here is a pic of my passenger side valve area - tell me if you see anything wrong here:


Also, here is a WAV file of both valvecover areas. The first half is from the driver side and the second half is from the passenger side. I know it's kinda hard to tell anything, but I recorded it anyways.

http://langhoff.dhs.org/valves.wav

Dunno if I'm just going crazy or if anything is really wrong. Any ideas would be greatly appreciated.

Langadorf

Also, concering the small faint white puff I see out the passenger exhaust:

This puff is really faint - I can't tell if its oil or water based and I have to strain to see it. I don't have an intake water crossover since I'm running an LT1 motor so it couldn't be leaking there. The head gaskets were new when I installed the heads and I had throroughly prepped all the surfaces. I also torqued each head bolt down (threads covered in sealant) to 65ft/lbs using the correct tightening sequence.

I'm running straight water w/ redline water wetter. I topped off the
radiator last night after not running the car for 4-5 days - it was
down a little. Then, I ran the motor for well over an hour today and
I just checked the radiator a few minutes ago. It doesn't seem
to be down any considerable amount - maybe a 1/4" from the very top
just below the overflow hole. If I was burning water, wouldn't it be down more than that? And wouldn't straight water be invisible?

Dryseals

Did you calculate the extra load on the lifters using the 1.66 RR? Seen a lot of folks go to 1.6 and have lifter troubles.

427Hotrod

Just a couple of things maybe...

First, are those the same rockers you always had? I don't see any pushrod guideplates...are the rockers the type that straddle the valve stem?

If so, maybe during the porting and ensuing valvejob, the stem tips were surfaced to equalize the stem heights and a rocker is touching a retainer?

Maybe a valve was sunk too far and geometry is off? But it would have to be pretty bad. But I have seen where guides were replaced and the valve got all out of whack as far as proper angles.

Remove all rockers and lay a straightedge along the tops of valve stem tips to make sure they are all at same height. Also look closely at them all for the wear pattern where the roller hits stem to all be similar and centered on stem tip.

How much total lift do you have now? Any chance they shimmed springs too tight and you have one stacking solid or maybe some new guides aren't at right height and a retainer is smacking it?

Also seen where an inner spring didn't seat properly and made clicking noises.

Check bottom of all rockers. Often a misangled valve, or weird retainer or bent stud (check with straightedge again) will allow the rocker to touch the outer edge of retainer on the bottom side of rocker.

Piston to valve clearance? Anything change to cause issues? Head gasket thickness etc?

Rockers hitting valve cover edge or baffles? Pretty common. Can you "feel" it through the cover with the engine running? Lossen cove with it running and scoot it around a little and see what happens.

For sure you have them adjusted plenty tight enough to eliminate clearance. In fact most folks don't go that tight, but it will work for now. When you really start twisting that cam into the range it wants to go, you might want to only tighten them a 1/4 turn or so from "just hitting zero lash". I mean JUST as it takes up slack, no extra preload. THen tighten 1/4 turn and lock down nut.

I'll try to think of other things, but this will give you a little to work with hopefully.


JIM

VetteLS6

Fire it up with the cover off and see if that adds any new info...My confiruration is all mechanical after I make any adjustments on the valves I run it with the cover off...a bit messy but it leaves no doubt of the status in there. From the picture it appears the rockers aren't centered correctly on the valve stem. Retainer clearance could be a issue as well. Does the noise go away as the RPM changes? Are the heat crossovers plugged? hmmmm could be a echo of the exhaut pulse in the header if all other things check good. Do you have a equalizer tube down stream in the exhaust system, this sometimes can cure the exhaust pulses and help with more consistant scanvenging.....this is interesting :confused:

belair55

Are you using self aligning rocker arms? If not that is at least part of the problem. The noise that you decribe sounds like valvespring coil bind, this happens where there is not not enough spring pressure for the valve lift. Are the springs matched to the cam profile. :chevy

Langadorf

It's hard to tell in that picture, but I do have guidplates installed on all the pushrods. I used new hardened pushrods (same length as the old) when I installed ported heads. Here is a picture before I mounted the heads in the car:



These are the same non-aligning roller rockers I used previously to have the heads ported and they worked w/out a problem. The rollers are meant to just press on the tops of the valve stems. My head porter didn't have to adjust the stem heights nor did he need to do a valve job (already had one and he didn't hit it during his work).

My total lift is .544i and .576e and this the same rocker ratio and cam I've used previously before the porting.

My springs are the same I had used previously (correctly rated for my cam), but my head porter said they were installed by the previous machinist at the wrong height giving me insufficient spring pressure. He installed shims to correct this and obtain the correct pressures. He also installed new posi-valve seals when he did the work.

I'll have to check alignment on the valve stems and studs.

Piston-to-valve clearance shouldn't have changed (and wasn't a problem before) since I'm using the same heads, pistons, and same thickness head gasket.

It doesn't seem that I can feel any especially loud vibrations through the valve covers. I've had them on and off 6 times so I'd think if it was interference I would have fixed it by accident already, but I'll give it a check.

I'll also have to remove the valve covers and look what's going on when the engine is running once it stops raining around here. I've got a HV oil pump so I'm afraid I'm gonna make a huge mess when I do this though.

Thanks for the input! If anyone has any further ideas while I wait out the rain, let me know.

MCAF84

I don't know if this will help but......

I had a similar problem with a set of 1.5RR I had bought
I put them on adjusted them for 1/4 turn after zero lash like I always
do, and I had an erratic loose lifter sound. It would one time be in the front
another time in the back, left side then right side. It kept moving around.

I had never had problems adjusting valves.

I started changing the way I adjusted them.
While running cold
While running hot (What a mess both times. Cardboard can only cover so much)
Motor off but hot
I went so far as to try different preloads
1/4 turn 1/2, 3/4, 1 turn untill the motor would bearly run ( didn't want to wipe a cam lobe)

finally just left it alone because the motor ran fine at 1/4 turn preload it just had that erratic clacking noise

About a year later I swapped to a set of 1.6RR adjusted preload to 1/4 turn
and no clacking noise. WHAT!! thats all it was
Well I'll never buy that brand again.

Later on I built another motor and I used those same 1.5RR thinking I would
put up with clacking noise, Well their was NO lifter/rocker noise NONE
I never did figure out what the H*ll happened

See I told you this would not help much

Just sharing my story
Good luck Mike

427Hotrod

The only other thing that jumps out is the new spring installed height. Make sure you aren't getting any coil bind on the inner OR the outer spring. Often the inner one will stack up. Also different seals might be hitting retainer or the inside of spring.

You may eventually want to either get some two piece guide plates or cut the ones you have to allow you to center rockers over valve a little better.


Similar story... I had a valve all of a sudden start ticking once. For no real reason it seemed to start after I had had it all a part for a freshening. I had made sure lifters and cam stayed mated. I narrowed it down to which one it was and set it at least 100 times it seems, swapped springs, lifters, studs etc etc to try to isolate it. Tried a new roller rocker. Nothing worked. BUT..if I installed a stock rocker on it it was dead quiet. Put the roller back on...tick tick. I double checked every clearance I could imagine. It ran fine otherwise and it was at the beginning of the summer season. I ran that sucker for a year that way even driving from TX to Illinois for the Street Machine Nationals and it never made a sound or acted up. Later I changed the cam and a buddy of mine wanted it, so I gave it to him. To this day many years later, it is STILL running in his 396 Nova with stock rockers on it and runs fine.

Go figure.....

Keep trying tpo narrow down WHICH one it is.

JIM

Langadorf

I removed the passenger side valve cover today and started the motor, and didn't hear anything wrong?! I didn't let the car fully warmup, so I don't know if that makes a difference. I can see that some of the rockers are *slightly* off center, so I'll try moving the guidplates around to get a better angle.

The one thing I noticed is that there wasn't oil just shooting out everywhere. All the rockers were getting oil, but it seemed to just be slowly pumping out. On my oil gauge I'm getting over 60 PSI when the motor's cold and around 40 PSI when it's warm. I'm watching w/ the valve covers off at around 700-1000 RPM. Is this ok/normal?

VetteLS6

It sounds fairly normal to me at Idle....if you rev the engine up the flow volume should increase that then the oil will squirt out a bit more. On my BBC with the LS7 pump (hi volume, Tall gear) it flow more so it tends to get a bit on the inner fender and fender when the rpms come up. GM makes oil deflectors just for this reasons...they are cheap too.
:cheers:

Langadorf

Well I went through and looked at the rocker/valve stem alignment for each pair of valves. I adjusted/flipped the guideplates to line up any that were misaligned. While I was doing this I noticed one or two valve stems that seemed slightly shorter than the others. Here is an example:



It seems that I've gotten the rockers to line up fine anyways. Is that a problem or should it be OK?

I took a quick video showing the rockers with the engine running. You can hardly see but there is oil slowly pumping into each of the rockers. Tell me if anything seems to be out of place. I still think I hear that original noise I was talking about occaisionally. I'm not sure if I'm crazy or what. Here is that video (1.5 MB).

http://langhoff.dhs.org/rockers.avi


[Modified by Langadorf, 10:23 PM 1/1/2003]

VetteLS6

If there is no sign of scuffing on the retainers then I wouldn't worry too much about the stem being short if the roller is centered in the stem. If you increase the rpms...is there more oil? Do the rockers have oil restricting holes? It would throw more oil at say 1800-2000. I can't even get a pic on here from Boomspeed.com they aren't posting and you have a video...I'm jealous.
Larry :rolleyes:

Langadorf

When the RPM increases there is an increase of oil. It flows quite well once you get above 1500 RPM.

VetteLS6

My previous Statement of the roller being centered is actually critical...if the roller doesnt presses down off angle it causes premature wear to the guides. At this point oil isn't a issue. With proper lash from all indications there shouldn't be any troubles. One thing I would keep track and it's subjective at best. Try to monitor for an increase in valve train noise, that is sure sign of gong bad. I would run it over to the shop that did the head work to get their opinion on it also so they are in the loop should it get worse.
Good Luck,
Larry :seeya

Langadorf

After my guideplate adjustments last night, all the rollers look to be in full contact w/ the valve stems except for two or three. These two or three look to contact the stem w/ about 90% of the roller. Is this OK or should I buy new guideplates?