cbh148

My redtop has always had a loud head for the year that I've owned it. It's been rebuilt and has about 5000 miles on it. A year ago, I took the lifters out and hand-bled them to try to shut them up, but it didn't change shit.

Just the other night while quietly driving home, the car died as I slowed down to a redlight. I cranked it back up but it was acting like it was on 3 cylinders. Drove it home and it acted fine on all 4 cylinders until I got to the next redlight 3 miles down the road, where it idled low. And during that 3 mile stretch, it started making a harsh rattle sound that went away once I revved. More on that sound later.

It seems to be kinda consistent -- runs on 3 cylinders most of the time at low RPM and always runs on 4 cylinders above maybe 2000 RPM. Also, it suddenly started making this god awful racket from the head that goes at the exact same rate as the cam (I took the oil cap out to verify) when it's at low RPM.

I thought maybe it was a bad lifter, so I took the valve cover off and video'd it running today. Also, I just took the cams and all the lifters out to inspect them. Every one of them was rock hard until I stuck my allen key down in the little holes and hit the little springy valve that makes the lifter all squishy and smooth. I just ordered 8 new lifters from RockAuto for $60. They're "EngineTech" brand. No idea if they're good or not, and no idea if they'll help at all, but I'm kinda stumped here and just decided to try them for the hell of it.

I was thinking maybe a bad lifter would make the cam lobe's movement get kinda wasted, since it wouldn't be opening the valves quite as wide as normal, and also would be causing the valves to open later and closer earlier. And then perhaps this narrower "valve window" was causing it to not fire on that cylinder if the timing was low (as in, lower rpm's) but then allowing the cylinder to fire at advanced timing (which always occurs at higher rpm's).

No idea if my theory is possibly correct or not, that was just me brainstorming trying to relate the random 3 cylinder 4 cylinder crap with the random loud ass head noise, which both started occurring out of nowhere on the same quiet little drive (my Megan turbo manifold is cracked and I'm waiting on my custom manifold, so I just never get on it at all).

Checked the cam timing and it's perfect. Pulled the oil pan to beat the dent out of it and noticed I have an s14 oil pickup tube, and that the pickup tube's mouth was a little curled inward from the pan touching its lips, but since it's an s14 pickup tube with the side cuts to the mouth, I assume it can't be choked out by the pan like on an s13 pickup tube.

More info about the oil pan dent: it was on the front of the pan, not the middle, and it happened about a month ago. Car has been daily driven the entire time. Seems like if it was gonna cause an issue, it would've been immediately or within a day or so.

No aftermarket gauges other than boost gauge, but my oil pressure dummy light works and it doesn't ever come on while running the engine.

My cams have always looked a little worn. Don't know if they're any more worn now than they were a year ago. Here's the pics/vid.













Any advice/insight is greatly appreciated!

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jr_ss

Have to checked your shim clearance? It may not be related to your lifters at all and it is just out of spec on the shim side of things. You said all of the lifters were hard as a rock when attempting to squeeze them with your fingers. I would say that the lifters themselves are fine, if you bled all air with them sitting in a cylinder of oil, while pumping the bleeder inside. Good lifters will not bleed down. A lot of times the head will be noisier on start up if a lift/s bleed down when sitting. Have you noticed any of this?

The cams do "look" worn and it looks like there are ridges on either side of where the rocker pad rides? Id recommend replacing your cam/s as that may be part of the problem. If you can, stick with a stock set until you get your noise sorted out. Introducing a "new" part may change things or just cover up an underlying issue.

The oil pickup looks slightly damaged. You obviously drained the oil, did you see any metal? I would reassembled everything with better condition factory cams and the rest of your existing parts and see if it changes anything. Based off your claims I highly doubt it's the lifters. Make sure your cam oilers are free from debris blocking the orifices and check your clearances between cam base circle and rockers, the spec is in the FSM. If they are out of spec, correct it.

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Kingtal0n

In the video it doesn't look like the camshaft (especially #1 intake side) is getting proper oil flow. I think debris has clogged up some of your oil passages. And this is a very very common thing to happen after a rebuild, which is why I always tell people not to rebuild these engines.

If you are lucky the noise is just shims/guides related. It is not your lifters.

vJilly

someone figure Casey's shit out because now he has to drive his Honda and as grandma always said: "why not stunt when you can stunt?"
-Vince


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cbh148

Well, I went out to the car a couple hours ago and took pics of all the shims on top of the valve spring retainers before I messed with them, then I carefully took all the shims off with a magnet and saw scraps of metal underneath most of them.

I organized each shim and the scrapped metal fragments (or thinner shims) that were underneath each one on some printer paper.

I'm assuming it's not supposed to be like this, and I'm really hoping this explains the godawful sound coming from my SR's head.

Thoughts?

ImageUploadedByTapatalk1402530073.932531.jpg
ImageUploadedByTapatalk1402530162.948095.jpg
ImageUploadedByTapatalk1402530279.079696.jpg
ImageUploadedByTapatalk1402530295.413282.jpg

And this is what they looked like before I removed them:

(Intake cylinders 1 through 4)
ImageUploadedByTapatalk1402530433.901142.jpg
ImageUploadedByTapatalk1402530450.017662.jpg
ImageUploadedByTapatalk1402530464.501506.jpg
ImageUploadedByTapatalk1402530511.867920.jpg

(Exhaust cylinders 1 through 4)
ImageUploadedByTapatalk1402530539.917918.jpg
ImageUploadedByTapatalk1402530551.167847.jpg
ImageUploadedByTapatalk1402530567.868221.jpg
ImageUploadedByTapatalk1402530581.851093.jpg



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jr_ss

Looks like they tried to reshim the head with those worn cams. Replace your cams and shim accordingly.

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angel mkiv

And when you dropped the oil pan were there any metal shaving at the bottom?or shiny/metallic looking oil?id for sure replace that oil pick up and while there visually inspect the bottom end for anything obvious before starting it again

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brndck

Dd you bother with a compression or leakdown test?

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s14SRguy

start with shims and cams.

similar thing happened to a friend of mine.

he was lucky enough to just need new shims. We pulled some out of a infiniti G20 FWD SR from the local pick a part, checked them with a digital caliper, installed them, and now its all good and running strong.

We did get lucky on the G20 however. The engine was pretty well kept. Shame to have seen it sitting in a junkyard.

I do not advise nor recommend using pick a part internals.

cbh148

Wait, so his shims went bad on their own? And was his car randomly going to 3 cylinders and back to 4 like mine? And did his have metal fragments underneath the factory shims?

I think my factory shims are fine, they just had some extra non-OEM shims added beneath them at some point in their lives, and those extra shims all failed and crumbled to bits.

I went to my friend's house this evening to get a set of stock cams from him, but they look to be worn similar to my cams. And while I was at his house, I popped off all the factory shims on his extra SR head to make sure none of his had any extra little shims or metal fragments beneath them like I just found on mine.

As I expected, his didn't have any extra shimming like mine. That being said, how would G20 shims help me at all? Because I'm assuming that the problem is that my stock shims are not enough to keep the rocker arms pressed up against the cams for quiet operation, hence why somebody added extra shit in there to try to correct it.

Or is it possible that the extra shims (which I'm guessing were kinda "MacGyver'd" in there since they goddam crumbled to bits) were actually causing the cam wear and/or the crazy noise?

All I know is, my head has always been noticeably noisy, but the crazy cam-paced knocking sound and this random 3-cylinder-at-low-rpm-sometimes-yet-4-cylinder-at-higher-rpm-everytime behavior started during the same exact drive, so these 2 issues have got to be extremely related. Could my shimming scandal possibly cause the random 3 cylinder issue?

How do I go about this? By getting more non-OEM extra shims to put underneath the OEM shims? And where would they come from? I did not see any noticeable metal shavings in the pan or in the oil. We looked carefully at the oil and did not see anything significant in it. The oil pickup is the good blacktop style, and looked to be in great condition other than the lips being slightly bent inward (like in the pics), but I bent them back straight with a flathead screwdriver before putting the oil pan back on. I have yet to do a compression test or a leakdown test since the random 3 cylinder 4 cylinder godawful head racket started 6 days ago. Last time I did a compression test was last August, and these were the results.


Also, here's some pics of the cams I picked up from a friend this evening compared to the cams I've been running.



Thanks for all the help people! Keep it comin'! I really wanna drive this bastard soon, especially since I just got my NX cluster in and wired up just a day before this shit started happening!

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Sileighty_85

have you bled the lifters?

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jr_ss

If his cams are no better than yours, I suggest finding a pair that are better.

Those "extra" shims should not be needed. You should have only ONE shim per valve, not additional shim material stuffed under the factory one.

Each shim is or may be a different thickness. You can purchase thicker and thinner shims for your head. The G20 shares the SR engine and shitty head design that is the SR. He obtained those shims to replace a shim and/or bring his head back into factory spec.

You seriously need to download the FSM or purchase one, there are maximum and minimum specs for this type of thing and you should follow those guide lines.

Take better pictures of the cam lobes, the ones that ride on the rockers, not the journals, which are held by the cam caps. What are those markings on the cams? Can you provide better pictures of those numbers vs the factory cams.

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s14SRguy

Yeah my buddys problem was a tossed rocker arm. Homie put on a t28 hks wastegate actuator on his t25 without properly adjusting it (he eyeballed it lol came out to be pushing 15 lbs...he learned his lesson)

He did a rebuild and thinks maybe the shims weren't put on right in the first place.
This plus hard boost led to a tossed rocker arm and missing shims (found in oil pan)

Very similar noise minus the sound of a rocker arm banging around. Alothough one arm was tossed, all the shims were done.

Replaced shims, we put the rocker arm back, turned down the boost to ten, and its still running strong.

Get new shims and cams while your at it

cbh148

Yes, I bled them a year ago because of the annoying amount of sound they make, but it didn't make any difference.
But this new hellacious, almost-catastrophic sound that just started 6 days ago (along with dieing when slowing down and randomly going to 3 cylinders and back to 4) is on a whole 'nother level than the annoying head sound it's normally made over the year I've owned this redtop.

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s14SRguy

Check compression and do a leakdown test. That will give a better idea of what the problem is. You can rent the tools from your local autozone.

Your shims are fucked, get new ones. If your broke find a 93-95 sentra se-r or g20 and pull the shims out make sure you measure them first. I'd say get new ones though

Get new cams while your at it. Those got ripped up from your shims.


Do all that first and get back to us with the results. Check your timing and spark as well.
Pull codes too.

Without that information there's not much we can do over the internet

aga

thing is, if you ve been running the car like this for a long time, you may have damage to the valves and the valve seats... it's just guesswork, you'll never know unless you remove the head, and that costs money.

anyway, i would get a new set of cams, replace everything that looks damaged, reshim everything and hope for the best.

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cbh148

It kinda sounds more like he just got replacement shims and a rocker arm simply because his was dropping that rocker arm frequently, rather than because his made the terrifying mechanical sound mine makes, whereas mine has never dropped/broken a rocker or a shim for that matter.
Are the OEM shims still available to purchase in all the different sizes that the FSM states they come in? I would hope so since some G20's aren't all that old.
I have FSM's out the wazoo, including the glorious color searchable s15 FSM. From what I can tell, I need a dial gauge and some means of attaching it to the head to measure shim heights. Looks like the focus is just simply to level out the rocker arms across the 2 valves they each operate. From there, I suppose the hydraulic lifter handles the precision of keeping the rockers in smooth, constant contact with the cam lobes.
All cams say "53J" toward the cam gear side. Only my old intake cam has the writing "AA33CB" on the shiny outer edge located right by the cam gear. None of the other cams are shiny on that area.
New Intake Cam: 12
Old Intake Cam: 1
New Exhaust Cam: 12
Old Exhaust Cam: 8

And the requested pics good sir.




Intake cams (Lobes 1 to 4):



Exhaust cams (Lobes 1 to 4):

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cbh148

Just as an update, I still haven't compression tested it, but I'm going to when I get back home tomorrow. This should work out well because I'm picking up another pair of stock cams tomorrow from another friend, so hopefully they're in better condition than the 2 pairs of stock cams I've already got.

I just don't want to even bother bolting in worn out cams to compression test it if I don't have to, because if it tests out to have good compression with no bent/broken valves, then all I'll need to do is shim the rockers, which won't require removing the head or anything.

And if the compression test reveals a big problem with the head or valves, then the other good news is that 2 other friends of mine have extra stock SR's with spun bearings just sitting in their garages, so the heads should be good, and they said I could get them if I need em.

I'm assuming that my compression test numbers might be a little lower due to my valves not being shimmed up as tight, causing the intake valves to close a couple degrees earlier in the intake stroke, creating a bit of vacuum at the end of the stroke before coming back up for the compression stroke. But regardless, the compression test should still reveal if a cylinder has a bad valve or not.

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rc1honda

I think you have some bent valves. My head was really noisy as well. Turned out I had like 3 slightly bent valves.

As far as shimming it really shouldn't be that big of a issue as long as they aren't way outta spec. The hydro lifters adjust lash accordingly.


Sounds like the guy previously popped a rocker and might of dropped a valve and then tried just replacing the lost shim or guide.

I would do the leak down, But chances are good that you'll have to pull the head and get new valves installed. Get it ported and hot tanked while it's there.

Also did you notice any air pulsing through the oil cap while running?

jr_ss

This very well could be possible. Banging off the rev limiter or over revving your engine can do the same thing.

They adjust to a degree, but you still need to be within factory specs for that "theory" to work.

That whole head has been fucked with. He needs to go through it and straighten up the half assed work that's in there. Going back to the first comment, you may have to pull your head and take it to a machine shop to square it away for you.

If you don't plan on making north of 400, don't waste your money. If you do and want "big" power, again don't waste your money on this head. Buy a VVL setup and build that.

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vJilly

yes. Casey. what have I been telling you? this guy knows what's up. Mazworx VVL or bust.



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cbh148

Ok, big update time.

So I got another redtop head from a friend 2 days ago. It came with a 3rd set of cams as well as all the rockers/shims/lifters/etc. The cams seemed less worn than my other 2 sets of stock cams, however they did have some light rust spots on 2 lobes. Seemed like just corrosion from moisture, and I felt confident that they'd clean up themselves once installed (like brake rotors do). Seriously, very little corrosion. Should've taken pics of that.

I installed these "new" cams in my head this morning. I reused my original lifters since they seemed to pass inspection and get nice and firm after carefully bleeding each one. I also used the rockers and shims from this new (to me) head.

I was thinking that, perhaps, this would fix my issue because I did notice that my original cams do have edges on the sides of the lobe faces, where the rocker touches it and has effectively ground down the metal just enough to make a step that you can snag with your fingernail on either side. I figured this, combined with the fact that I was putting in shims from a different head (although they don't look any different than my original shims) might remedy the head noises -- both the typical loud head noise it's always made since I got the engine 1 year ago, and the godawful knocking head noise that just started randomly occurring 2 weeks ago.

Well, I fired it up and right away I could hear the typical noisy head shit that my SR has always had. Bummer. I let it idle for awhile and sure enough, after 5 minutes or so, it started randomly stumbling to maintain a steady idle completely on its own without anybody touching anything, and right then it started making the godawful head knocking sound.

Now that it was up to operating temp, I decided to compression test it. Cylinder #1 spit out 153 psi. Cylinders #2, #3, and #4 all pumped up 170 psi, however, a good bit of oil had puddled up in their sparkplug wells, so I'm sure that when I pulled the plugs to connect the compression tester, this oil rained down and accidentally converted those tests into "wet" compression tests (ie, what one would normally do to determine if their low compression numbers were the result of piston ring wear).

To verify this, I added a capful of oil to cylinder #1 and retested it. It, too, read 170 psi, just as I expected it would.

After the compression test stuff, I reassembled everything and shot a video of the sound just for you guys with the Canon.

Sound occurs at 3:00 and 4:25. Smoke is from the oil going in the cylinders during the compression test. Sorry for the focus issues during the oil cap removal and the gauge cluster viewing. Be sure to go highdef for the crisp audio.

https://www.youtube.com/watch?v=4U8XS2_DLr4


As always, thanks for the valuable help everybody!

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vJilly

look at that goddamn amazing video. I wonder who was the behind that camera.

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jr_ss

Have you tried pulling a coil at a time to see if the noise goes away by any chance? The shims can be different from valve to valve. With the rockers sitting on the valves and the lobes not pressing down on the rocker, can you compress the lifter at all? You may have to rotate the motor over by hand(easiest to do it with spark plugs out) to do each one. If they move at all by hand, you need to re-bleed or replace that lifter. Did you verify that your oiling tubes were clean of debris that could possibly be blocking any holes?

It also looks like you have an exhaust leak, that can be adding to the noise.

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cotbu

I agree, you definitely should re shim the head, or measure all shims and label the current valve they belong to, then using math and science to make the rocker arms as level as possible.

I also hear that exhaust leak.
After you rev(4:20) the rate of the noise is faster, which would indicate at least 2 rockers are affected or top and bottom slop in a rod bearing.

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vJilly

his manifold is cracked like a butthole

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cbh148

Haven't tried pulling any coils because the sound is so mechanical sounding, but it can't hurt to try it anyway.

So the shims that come on these engines straight from the factory are different sizes? I know the differences between the factory shim sizes mentioned in the FSM's are frickin' miniscule. Not that I'm saying it's unimportant, but I mean come on, the knocking sound is so loud, and the cams aren't spinning fast. Just doesn't seem like a tiny ass feeler-gauge-worthy gap (if there even is one) would allow hardcore-ass mechanical slapping like what mine is doing. Plus, why would it come and go? And how could that suddenly cause the idle to stumble and stuff right before/during/after the harsh mechanical sound?

My lifters can't be compressed at all. I tried to compress them before taking my cams out almost a week ago, and I tried again today when I re-bled them and reinstalled them. My RockAuto lifters are here, and they are the "updated" design with the bigger sidefeed hole and smaller top hole. I didn't install them because I was trusting you guys' word that my original lifters are operating as they should. Perhaps I should throw these new RockAuto lifters in anyway? If they didn't fix the problem, maybe I could still clean them up good and get to return them.

I never thought my oil tubes were clogged, but I stuck a pick tool into every hole on the oil tubes today anyway just to be safe.

And yes, my Megan turbo manifold is cracked. In person, you can clearly tell there's an exhaust leak sound. But you can also clearly tell there is the mechanical slapping/knocking sound from the head too.
Thanks for helping dude!
Well according to the FSM, making the rocker arms as level as possible is less about "math and science", and more about "having a dial indicator". For the sake of being thorough, I screenshot'd the FSM info about it (from an s15 FSM; I assume there's no difference in regard to the lifters/rockers/shims/etc.)



And could you explain what you mean about the rate of sound increasing along with me revving it and how that would indicate specifically 2+ rockers or rod knock? I don't think I follow clearly lol. Thanks for the help!

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cotbu

Clearly you already don't believe the small differences in shims matter, so I'm sure you don't have a dial gauge laying around to re-shim the head. This plus that, minus that and the way you think about what you're trying to do, equals math and science

(Maybe I'm not hearing what I think I am)
The rate of noise got twice as fast. When the engine speed slowed down. Just assuming 1 rocker arm was making the first noise. Theoretically the second sound was coming from another rocker arm. If this sound isn't what it appears to be it could be the sound of the slop in a rod bearing, top and bottom, as oil pressure builds the sound stops. I would easily rule out those things and that's all I'm suggesting you do.
Regardless of what you think you know or understand. Put the new lifters in, just because or reshim the head, but if you still have the noise after that are you going to blame the lifter or the shimming
G/L.

Oh and this is the "The rate of noise" i was referring too:

Sent from my Highly Tuned Galaxy S3.4!!!that

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cbh148

It's not that I don't believe the small differences in shims matter, it's just that the godawful sound my engine is making (that comes and goes) is far beyond the level of volume that such a miniscule shim difference would make. Now the typical noisy head sound that the engine has always made? That -- that I could attribute to the miniscule possible shim differences. However, one would think that since I swapped out all my original shims today with a full set from my new SR head that, if the shims were such a huge factor in this whole equation for the godawful sound, then there would've been some significant change in the sound's behavior/volume, but there was not.

And on the subject of hydraulic lifters -- as mentioned earlier in this thread, their main objective is just to keep the rocker arms pressed upward onto the cam lobes for zero clearance and silent operation. And once again, as mentioned in this thread, for HLA's, the shimming is done just to get the rocker arms perfectly level (unlike on solid lifter setups, where the shimming is done to not only yield a level rocker, but also to set the fixed clearance between the rocker pad and the base circle of the cam lobe).

So knowing ^that^, if my factory shims are improperly sized (if Nissan does indeed send these heads brand new out of the factory with different sizes of shims in the head off the dealership floor [not talking about the fact that you can order OEM shims in different sizes]), then the "error" we're talking about here is once again not an error of clearance like a solid lifter with improper shims, but just an error of rocker arm level-ness. Meaning, how in the flying phuck is it so loud? Not to mention, how is it causing the cylinder(s) to randomly miss at low RPM and not at high RPM.

I'd like to check my oil pressure to address whether it's rod knock or not. I need to go buy an oil pressure gauge. And hopefully if I try out these new lifters and it doesn't fix the issue like several clues suggest (such as my seemingly perfect original lifters) then I can get my $60 back to put that money toward a new long block.

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rc1honda

It's the valves man. You have one or more bent valves.

Do a leak down and try to find where the bent valve is. You can replace the valve without pulling the head you just have to pressurize the cylinder.