hey all any ideas:

1.) valves are set to .007/.008 they are set very well
I ran through them again today making sure a larger
size could not fit, yet the proper size is snug.
2.) the timing belt tension is proper, the deflection is
the size of a 10mm wrench opening.
3.) VTEC is intermittant
4.) Oil pressure never throws a light, oil level is
4+ qt directly after shutoff.
5.) cams are set to dead 0,0 on my gears and the
valves were adjusted here.
6.) timing is at 16BTDC
7.) idles perfectly, no stumbling, no hesitation when
revved, good transient response to motor
8.) sound is not present at idle only after say 2500
under any kind of accleration and WOT and narrow
throttle does not change behavior
9.) power under VTEC is weaker
10.) I have 98 CTR/01 ITR cams


Hypothesis:

My car ran great until I adjusted my valves when still
kinda warm this Wed. I had a few kinda tight, and I still buttoned
it up and ran it hard. (dumb) once it warmed up completely,
no doubt they were tighter than they should have been,
and I think this weakened and later worked my LMAs due
to running more lift at the valves than normal.

the sound comes in at 2500 and remains through
the revband and does not get louder, the engine
muffles it after say, 5700. It is most apparant under
accleration. It is a thin, tapping/hammering sound
on the intake side of the motor. holding the sound
constant and removing the spark wire does not
stop the sound. It is resonating in the head, under
the valve cover. The deflection in the timing belt is
non-existant with the cover cut and the upper belt
cover removed the belt is stable and has no flap in
it at all. Its the best I ever got it honestly. Throttle
response is great low end, power on the low cam
is very good. It sounds like the pitch of a large coin
on a peice of glass, not deep or hollow like it is hitting
a solid surface.

I think I may have destroyed the Lost motion assembilies.
Can anyone advise here?

 

Unfortunately, this isn't something you can diagnose without checking first hand.

 

This is how my problem started. There's a number of other guys on the board with similar noises, and we're pretty much all asking the same questions. I had the same power loss and problems, before the engine started tapping like that at all rpm's. If you take it in to a shop, would you mind shooting me an email letting me know what they found? I'll do that same if I find out whats wrong with mine and it might give you a good direction to look at the very least.

Here's a clip, see what you think...
Ca-clank

 

You are positive the sound is in the head and it's not rod knock?

 

Damn... that sounds like a sticking valve or rod knock to me. That's downright harsh.

 

I swapped the rods out for Crower H-beams with new Wiseco pistons and made sure they cleared, and went through and inspected everything in the head. Here's the pictures:
Engine Rebuild

We've run the lash all the way out (careful not to burn a valve up however), adjusted the lash countless times, checked the springs, retainers and lapped the valves, removed the Vtec followers, you name it. After six months of massaging the engine the best we can, my buddy and I are stuck without a clue. I've been hoping someone on the board has had this problem (knocking from the intake side, closest to the #1 cylinder) and knows what the deal is.

 

Yes they may have cleared during the rebuild, but it doesn't take much to spin a bearing and start knocking. A little speck of contaminant is enough to spin a bearing, and eventually start to knock.

 

Yep, I go all doctor-like and clean the area I'm going to work in, scrub up to my shoulders and wear brand new latex gloves when I assemble a lower end. I don't know for sure if it's the lower end that's the problem, but it seriously sounds like a solid metal to metal hit, at a minimum I'd say it's time to rebuild the head again and check the condition of the lower end.

 

We tore the bottom end back off about two weeks ago to check the oil pump, (the car hasn't ran for more than 5 minutes at a time, and more than an hour combined) and checked the bearings out as well and they were fine. The clearances were all .001" exactly like they should have been, and none of them had spun. Everything looks normal by all indications. This wasn't either of our first buildups, and we took all the usual precautions, including liberal amounts of assembly lube. It started knocking again the minute we started it up. Thanks for the suggestions though. :thumbup:

 

I plan on taking the car to my friend chris who is a great diagnostic mechanic who has helped me out alot. he works
at the local acura store and he is very talented at working
things like this out. if I trip over some info from him and we
get it resolved, then I will definately share =)

by the way on my car:

since I discovered the issue

I have new 5-30w in it, just changed
the knock was present before and after the oil swap.
the oil before it was only in it 400 miles.
idle is unchanged, no spitting no stumbling
no knock at idle like in rooster's car, although
he did say thats how it started...
I think I will look back in my cam bearing surfaces
and see if the gauled up ones got any worse for
wear. when my engine sounded like rooster's,
I had over torqued bearing caps on the cams and
wiped about 4 of them, 2 of them completely clean.
one eventually stopped... it is then we removed them
cleaned the surfaces up and reinstalled. since the
engine seized a few degrees shy of BDC, there was
no valve contact. the engine ran PERFECT for 5K miles
without a burp, until I over tightened my lashes and
ran her hard for a day.

on this most recent thing, it sprung up after making
the valve lashes too tight (my theory) my sound is not
a low/medium pitch, it is a quick sound like a marble in a glass...
higher pitch than even a cam bearing this is why I think
I have a problem in the vtec assy. after running the car
hard with the wrong lashes, it really could be anything.
I rule out valves because I know what they sound like
when they bend and thats a tick. My motor does not tick
at all... you can hardly hear it when its idling. its very quiet
now as I went through it again and made the lashes perfect.
if there was any valve contact as of late... the idle would be
trashed and the car would be spitting and shuddering. if you
bend valves in the B series car, you will know it by God.

right now it has me scratching my head for sure. it is definately
mechanical, but if it were a rod, it would be deeper and always
present like a hammer on a 4x4 block of wood. I spun one in a B20A3 I had once and it was much, much diferent than this. The compression dropped when on the highway w/o warning and the knock was loud, deep and racous at idle and constant through the band. This sound is intermittant... and it has got me puzzled to say the least.

Only on accleration, VTEC is intermittant sometimes the click when the VTEC engages or disengages makes a series of snaps
sometimes it comes on, sometimes it doesnt. Regardless of
VTEC this sound only appears on engine speed acceleration, not on the way down and will do it at a constant engine speed above 2700 rpm throughout the rev band from there. I have only taxed it to 5500 since the clack in the motor was noticed.

I am broke for ideas until I can see my friend, so any ideas are appreciated. I could compression test her, I dont have a leak down tester. I can do that once I leave it with him.

cheers...