i have a jdm second gen b16, i notice that when the car is cold, and i start it up and the hood is popped, at around cylinder number 4 it sounds like a rock is being thrown around in that part of teh head, thats the best way i can describe it. it does it for a little while then stops then does it again, then after the car is warm, it doesnt do it any more. any ideas on what it could be? and how i could fix it?

 

anyone know?

 

take off the valve cover and make sure everything is on there tight, and then go from there

 

most likely, you have 1 or more bad Lost Motion Assemblies (LMA's). I had the same problem in my 1g b16a. I replaced them with ITR LMA's and the valvetrain is very quiet. If you are running larger cams, that would put excess load on the LMA's. Also, you might want to check your valve lash.

 

My guess is you just need to do a valve adjustment. Clearances are loose when the motor is cold, when it warms up everything tightens up a bit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kataku2K3 &raquo;</TD></TR><TR><TD CLASS="quote">My guess is you just need to do a valve adjustment. Clearances are loose when the motor is cold, when it warms up everything tightens up a bit. </TD></TR></TABLE>

Bingo . When is the last time they were adjusted?

Phil

 

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

Bingo . When is the last time they were adjusted?

Phil</TD></TR></TABLE>

or if you havent thrown a rod

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1Quikgsr &raquo;</TD></TR><TR><TD CLASS="quote">

or if you havent thrown a rod</TD></TR></TABLE>
What does that mean? A knocking rod doesn't go away when the motor warms up...

 

a knocking rod will be alot louder than what he is describing

 

well i guess the last time i adjusted the valves was about 4 months ago maybe a little longer, .007 intake .008 exhaust. but if the valves were outof adjustment, would they come out of adjustment on just one cylinder or all 4? also are the lma's hard to replace? i am used to v8 chevy motors, more so than dohc honda motors, i understand everything about them, except how the lma's work if they are worn do they harm the motor? i am getting ctr cams to put in and i wasnt going to upgrade the valvetrain, just keep the stock rev limitor, sould i hold off on this?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1Quikgsr &raquo;</TD></TR><TR><TD CLASS="quote">

or if you havent thrown a rod</TD></TR></TABLE>

its definately not a rod knock i know what that sounds like

 

pull your valve cover, and press down on the middle (big) vtec lobe. If it takes a second for it to return, then you have a bad LMA.

http://www.hondaswap.com/forum...42639

on a scale of 1-10, installing LMA's are about a 3 if that. very very easy. no special tools or anything. basically, just pull your cams and the rockers will lift up so you can pull the LMA's right out.

 

Yes, it's not common but if you didn't tighten up the rocker lock nuts quite the same then it could have backed off a hair. It could also be a flat cam/rockers but lets just hope that's not the case. That's normally caused from clearances being too tight and/or debris in your oil. You're stock vavletrain will be just fine with an R cam so do just as you said and keep your rev limit the same. LMA's are pretty easy to replace, but the cams do need to be out (so when you do your R cam check them out). They're located directly under the VTEC rocker, so just flip the rocker set up and pull the LMA out. I normally use a pick with a 90 degree tip since the LMA has a little hole in the side of the tip to pull it out. First things first, I would check the lash on number 4 (7thou/8thou is just fine). If you're loose tighten them up and see if you still have this clicking/knocking. If everything sounds fine then you're set, if not I'd pull the cams out and check over everything. I've had/seen LMA's go bad and they do make a ton of noise but that noise doesn't go away once the motor is warm so I'm still not thinking that's the case. Hope this helps a little. Good Luck

EDIT: Damn onezexycrx, you must type FAST... haha! When I started typing no one had responded yet.

 

thanks alot for the info guys, you've been a big help, unfortunately i work every day till friday so friday i'll pull the valve cover off, check the valve lash, and check the lma's by pushing on the vtec follower and then i'll get back to you and let you know what i find.