Could anyone spot a LMA going bad ? I've read they tick
as they start to go bad. Do they have a unique sound or
is it exactly the same as a valve needing adjustment ?

 

usually it sounds like an intermittant tick (relatively loud) coming from the valve train.

 

What exactly is the lost motion assembly? What does it do? I know what the parts look like but I didn't see a description of what they do in my Helms or Haynes manuals.

 

any more info on this??? what does the "tick" sound like...does it "tick" at idle or only under load????

 

It ticks at idle. It will go away when VTEC engages, or the oil pressure builds enough, but it comes back as the oil pressure drops back down. I have one ticking right now, too. I just haven't had the time to go in and figure out which one it is.

 

yeah, i've been wondering too. i'm not sure exactly what it does, anyone wanna explain

 

from what ive read it's sposed to keep the vtec lobe's rocker arm assembly portion from flappin around and making noise when it's not engaged.

 

.<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tilt &raquo;</TD></TR><TR><TD CLASS="quote">from what ive read it's sposed to keep the vtec lobe's rocker arm assembly portion from flappin around and making noise when it's not engaged. </TD></TR></TABLE>

yup, the LMA's keep the center rockers in control. The center rocker doesn't have any valve spring underneath it to keep it against the camshaft.

LMA's are cylinders with springs inside them. They keep the valvetrain quiet when not in VTEC. Without them, the VTEC center rocker arms would tick up and down.

You dont want too much motion. The pins inside the rockers must be aligned in order for vtec to engage.

Do a valve adjustment according to spec, and if you still hear the ticking...
it might be the LMA's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Quick 200k Mile Motor &raquo;</TD></TR><TR><TD CLASS="quote">.

yup, the LMA's keep the center rockers in control. The center rocker doesn't have any valve spring underneath it to keep it against the camshaft.

LMA's are cylinders with springs inside them. They keep the valvetrain quiet when not in VTEC. Without them, the VTEC center rocker arms would tick up and down.

You dont want too much motion. The pins inside the rockers must be aligned in order for vtec to engage.

Do a valve adjustment according to spec, and if you still hear the ticking...
it might be the LMA's </TD></TR></TABLE>

LMAs, one of the theories behind the breaking cams
https://honda-tech.com/zerothread?id=359458

 

Number #18:
http://www.acuraautomotivepart...82%29

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Quick 200k Mile Motor &raquo;</TD></TR><TR><TD CLASS="quote">You dont want too much motion. The pins inside the rockers must be aligned in order for vtec to engage.
</TD></TR></TABLE>

In that case, a bad LMA might theoretically show up as problems engaging VTEC.
Anyone have this happen ?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mover &raquo;</TD></TR><TR><TD CLASS="quote">In that case, a bad LMA might theoretically show up as problems engaging VTEC.
Anyone have this happen ?</TD></TR></TABLE>

I exaggerated a bit. Since the rocker arms are packed next to each other, they are influenced by each other. But I still think it could happen, if the lma's are worn...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PatrickGSR94 &raquo;</TD></TR><TR><TD CLASS="quote">What exactly is the lost motion assembly? What does it do? I know what the parts look like but I didn't see a description of what they do in my Helms or Haynes manuals.</TD></TR></TABLE>
And what do you think the level of difficulty is guaging by your helms manual? Any major maitenance like removing the head, etc.?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4gen &raquo;</TD></TR><TR><TD CLASS="quote">
And what do you think the level of difficulty is guaging by your helms manual? Any major maitenance like removing the head, etc.?</TD></TR></TABLE>

I'd like to know too!

Also, sorry to hijack, but would it be benefical to put ITR LMA's in a first gen B16 head, in anticipation for bigger cams? I hear stock ones can break at high RPM levels and ITR ones are a bit stronger.

 

the LMA's keep the middle VTec follower close to center cam lobe and kind of insync with the primary and secondary cam follows. Without the spring pressure underneath the VTec cam lobe follower, the VTec follower would just hang down toward head and VTec would never engage.

 

If there is any doubt about the LMA's, change them. My friends 1st gen B16a made lots of top end rattling mainly with a cold engine. We rechecked the valve clearance and it was ok. I bought jdm integra type r replacements from city speed on e-bay for a good price. The new integra ones had a beefier tip that contacts the rocker, and had tension compared to the mushy b16 ones. We put them in and the noise was gone.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Runnerdown &raquo;</TD></TR><TR><TD CLASS="quote">If there is any doubt about the LMA's, change them. My friends 1st gen B16a made lots of top end rattling mainly with a cold engine. We rechecked the valve clearance and it was ok. I bought jdm integra type r replacements from city speed on e-bay for a good price. The new integra ones had a beefier tip that contacts the rocker, and had tension compared to the mushy b16 ones. We put them in and the noise was gone.</TD></TR></TABLE>

A type R cam has a larger vtec lift and this cam should only be run with a type r lma. The type r's have more travel in them. All these stupid things are is sping loaded bucket cups. In order to replace them, you would have to take the cams out. they can be checked real easy just by pushing on them to see if they feel mushy or if they are broken and bottomed out.

 

i thought rocket checked them out and they are all the same.

 

I have bad LMA's in my B16...it sounds like BADDDDD valve lash....and Imtermittent.... Ive had my head apart...but not the LMA's....do you have to pull the head to change them..or can you just pull the cams...

 

no, you just have to take the cams out and pull the lma's out

 

you have to pull the rocker arms out if you want to pull the lma's. they hit just slightly to where you can't pull them out. this is from my experience. maybe some have a notch on the bottom of the rocker or something to get the clearance. this was a gsr head. b16 might be diff.