Hey guys,

Today while at the track, I was coming into the pits on a cool down lap and the engine started making this LOUD tapping noise. I took it out of gear and the tapping frequency reduced but the engine stalled right away. I tried to fire it back up but couldn't get it back running.

After using a friend's battery, we got it running but the excessive tapping was still there. After getting into Mark (aka mstewar's) garage, we fired it back up to try to locate the knocking sound. It appears to be coming from the front side of the engine by the upper timing belt cover, above the header. We did a compression check and all the cylinders appear to be fine. We took a look under the valve cover and didn't see anything obvious. The cam gears were TDC and the t-belt looks fine. Anybody have an ideas what it could possibly be?

Here are the two videos from tonight with the knocking coming from the head...

http://www.chillybanana.com/Vi...I.AVI

http://www.chillybanana.com/Vi...I.AVI

Any input would be greatly appreciated.

Keith

P.S. Special thanks goes to mstewar (and his gf + family), LudeHawk, Chris, Jacques, Grant and Joel for all helping Laura and I out today.



Modified by Keith at 11:24 AM 10/4/2004

 

Awww man, sorry to hear this.

First thing I would do is change the oil. Inspect the oil too.
Second step would be to pull the valve cover off to see what's going on in there.

Let us know what you find.

 

did the sound stop? it sounds like engine detonation. what mods are you running on your prelude, it might be good to go a step or two colder plugs and get it retuned, and use highest octane gas. If compression is still good, i dont think you did anything to your engine, but i could be wrong, i can tell you for sure, if the sound keeps going on you will hurt the engine, if it is detonation.

ok, after looking at the fid, it looks like your timing belt might of slipped or your valve clearences got out of whack. You can get them manually reset at a honda dealership, and i would suggest resetting the timing belt too. edit: also, it might of sliped because your tensioner is going out, happened to me.

I hope you get that fixed man, that sounds sucky, btw....if it is comming from a specific cylender, you might want to deactivate it as to not hurt that cylender, if you are going to limp it somewhere to get it fixed. this is not a real suggestion and i dont have any technical experience in this, so it might be a bad idea, but it makes sence to me, lol....could someone tell him if this is a horrible idea or not.

 

It's not detonation.

It's not the timing belt slipping, b/c for it to have jumped enough teeth for the car to smack valves like that, it prob. wouldn't stay running.

It sounds like a valve is tapping pretty hard. Start checkin the valve lash clearances, do a leakdown test, etc.

Did you overrev or mis-shift?

 

hey one 1 out of 3 aint bad, lol...yeah, first suggestion was before watching vid, and then went back and heard it, and it sounds like a valve. And yeah, is it comming from a specific cylender?

 

Deff valves.

You may have bent a valve, or you havent done a valve adjustment in ages, it finally decided to make noise at you.

Pull the valve cover, get out the feelers and check all the valves.


BTW 00Lude its Cylinder (hit the spell check before the post button)

 

sorry man, i knew it looked wrong, but i couldnt decide between cylEnder and cylInder, they both looked wrong for some reason.

but yessir, i will do spell check. hehe...

...man i am becomming such a forum ***** on this thread, sorry.....

 

Got the valve cover off, didn't see anything that stuck out. Compression was good across the board.

I didn't misshift... I hit the revlimiter a couple of times in 2nd but the ECU caught it and cut out on me.

Cams and belt seem fine... while the valve cover was off, we turned the crank to go through a full cycle a few times to look at any broken teeth on the belt.

I could try the valve adjustment.... I guess that wouldn't hurt and wouldn't take long.

Thanks for the suggestions and replies.... keep em coming.

Keith

 

If the valves were bent, the compression check would catch that, no? If it was a valve that is out of adjustment, then might the locking nut came loose. I did a valve adjustment late last year.

keith

 

when you are looking over the valvetrain, check that the middle rocker arms (VTEC rockers) move independently and smoothly. There should not be any slop either. If one of the LMA's has a broken spring the middle rocker could be bouncing on the cam. Good luck...

 

leak down test would tell you more than a compression will

 

yes if you had bent valves it would show in the leakdown. If you are bouncing your stock H22 off the rev limiter, sounds like you are over reving to me. Yes, do check the rocker arms, and if one is bad you have to replace the entire set of 3. (people have made the mistake of trying to do 1 ) I would highly recommend to atleast check your valves, its right fookin there while the valve cover is off no excuse not to.


Also, try not to bounce your car off the rev limiter, lol.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98TypeSH &raquo;</TD></TR><TR><TD CLASS="quote">yes if you had bent valves it would show in the leakdown. If you are bouncing your stock H22 off the rev limiter, sounds like you are over reving to me. Yes, do check the rocker arms, and if one is bad you have to replace the entire set of 3. (people have made the mistake of trying to do 1 ) I would highly recommend to atleast check your valves, its right fookin there while the valve cover is off no excuse not to.


Also, try not to bounce your car off the rev limiter, lol.</TD></TR></TABLE>

i hadn't heard of the rocker arm thing before, but sounds entirely possible..

putting an H22 off the rev limiter is over revving? if you're not hitting it on a mis-shift, it shouldn't go into a dangerous RPM range I would think.. but anyway..

the weird thing about this all is that despite the horrid noise, it seems to idle fairly well..

sounds like some things to check at least.. surprising no one has heard this noise before..

 

Have you pulled the valve cover yet? I mean, as in...did everything look in place. Try turning the crank with the cover off and look/listen for anything that's out of place.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by cheezthis &raquo;</TD></TR><TR><TD CLASS="quote">Have you pulled the valve cover yet? I mean, as in...did everything look in place. Try turning the crank with the cover off and look/listen for anything that's out of place.</TD></TR></TABLE>

yep.. didn't see anything that looked especially out of the ordinary though.. and turning the crank by hand did not reproduce the noise..

 

Its a rod bearing man. You get some crazy vibration or what?? Im retracting my other thought, if it were valve it would hit twice a rotation and wouldent be quite as deep. Pull the pan and check those puppy's out. you can hear it on the downstroke. man thats hairy.

 

That doesn't sound good...something is up with the block I'm thinking...it may be stalling cause the piston is damaged....drain your oil and see what it's in it...maybe pull the pan...

 

rod bearings?

 

Sounds like rod knock or possibly even piston slap.
I think you should empty the oil to see what comes out and also drop the oil pan and do a clearence check with plastiguage on the rod bearings if nothing is visually apparent.

Will

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">That doesn't sound good...something is up with the block I'm thinking...it may be stalling cause the piston is damaged....drain your oil and see what it's in it...maybe pull the pan...</TD></TR></TABLE>

Actually it's not stalling anymore Joel...

As promised, the video of when it happened...

http://www.chillybanana.com/Videos/bad_news.wmv

 

Pull the valve cover off and check to see if all your 10mm nuts you would use to do a valve adjustment are still their. Thats EXACTLY what happened to my R. I pulled the valve cover off to check and i saw that one 10mm nut from the intake side of cylinder 1. somehow loosened up and flewoff. Lucky it went down into the oil pan and didn't cause any damage.



Modified by SpdFrk at 7:05 AM 10/6/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Keith &raquo;</TD></TR><TR><TD CLASS="quote">If the valves were bent, the compression check would catch that, no? If it was a valve that is out of adjustment, then might the locking nut came loose. I did a valve adjustment late last year.

keith</TD></TR></TABLE>

I've had bent valves before and still very very strong compression, didn't know until the motor was disassembled that they were bent (the exhaust valves were all very slightly bent from a misshift). Leakdown testing will be a better way to check for bent valves.

 

You spun a bearing. I did the same on my H23, Knocks loud as crap huh? Take off your oil pan, look in tha pickup and if you got nice little pieces of that bearing in their you need your self a new long block, cause mine ran like yours did but the block was chewed up beyond repair, and the crank was just as bad as well as the piston rod.

Man lay off the cams people....

Oh yea and the oil pickup in these motors for some reason has trouble keeping the oil round the pickup when taking sharp corners, especially those nice long corners you can "cruise" round. Thus why you probably spun a bearing, no oil to the pickup, no oil to your crank...


Modified by F22bPrelude at 2:58 AM 10/6/2004

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by F22bPrelude &raquo;</TD></TR><TR><TD CLASS="quote">[B]

Man lay off the cams people....
</TD></TR></TABLE>

Are you talking about not using VTEC?? Kind of hard to when you are tracking your car and the engine is designed with that in mind.

Corey, if you read this, do you stay off the cam in the Honda Challenge???

Keith, good luck with the diagnosis. I hope it isn't bad.

I am kind of worried now. I have a track event in a week and a half.

 

Missed the point, most of you are saying the problem is this and that with his cams, adjust the cams etc... i never said anything about VTEC, i ment you all for some reason think the problem is something with his cams and its obviously not.