Rebuild Z6 engine mystery noise

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BoogieDown

Senior Member
when i was adjusting my valves today i noticed the LMAs would not move when the cyl was on the intake stroke is this right?

i also did a compression test and hears how it went
#1 195 psi #2 165psi (185 w/oil) #3 200psi #4 200psi.
there is a ton of blowby as well, like clouds of it from the oil fill. :`(

At 2000 rpm (just there it seems) there is a rattle comeing from what i think to be the valvetrain. When i take off the #2 plugwire it goes away. WTF is this????
It was there before i adjusted my valves(they where all too tight) and now its seems to be worse. All the adjuster nuts are tight, I have an OE headgasket. Clevit bearings and TopLine .020 Pistons & rings.

the engine has only 300 milse on it and has never seen past 4200rpm

When I get a chance i'm gonna re-ring it and mabey new ACL bearings.
What piston rings do you recommend. OE honda has std. and .025 over and I haven't really been able to find any others that are .020 over. I searched Yahoo and found companies that make them and B series rings.
 
At 2000 rpm (just there it seems) there is a rattle comeing from what i think to be the valvetrain. When i take off the #2 plugwire it goes away. WTF is this????


no real ideas for you but sounds like you messed something up...

did you alternate the gap sides on the rings?
 
Yeah I kinda had an idea that something was wrong. lol thx for that.

I had the engine rebuilt. I noticed the nosie a few days ago and adjusted the valves the same day and the blow by is the rings I know.(but doesn't smoke?) What I have nooo idea is the noise. The LMA bolts are tight and eveything from what i see is ok.

What nosie would go away when the #2 cyl is killed, only happens that I have
found at 2000 or so RPM. The spark plug looks like it has burnt oil on the side of the electrode. The compression in that cyl is low(165psi). Thats low for spark knock right?
 
Originally posted by BoogieDown@May 24 2005, 12:24 PM
Yeah I kinda had an idea that something was wrong. lol thx for that.

I had the engine rebuilt. I noticed the nosie a few days ago and adjusted the valves the same day and the blow by is the rings I know.(but doesn't smoke?) What I have nooo idea is the noise. The LMA bolts are tight and eveything from what i see is ok.

What nosie would go away when the #2 cyl is killed, only happens that I have
found at 2000 or so RPM. The spark plug looks like it has burnt oil on the side of the electrode. The compression in that cyl is low(165psi). Thats low for spark knock right?
[post=502938]Quoted post[/post]​


bump
 
they should all be with in 50 of each other...and according to that spec you are good...sounds like a valve leak (a valve is letting the compresion leak out)

and it sounds like that valve could shoot at any moment...
 
Originally posted by jdmlovingcrx@May 27 2005, 08:08 AM
they should all be with in 50 of each other...and according to that spec you are good...sounds like a valve leak (a valve is letting the compresion leak out)

and it sounds like that valve could shoot at any moment...
[post=504249]Quoted post[/post]​



sounds right, no load on the cyl with the spark killed no noise. I was talking to a guy at the Napa machine shop and he said its hard to over bore hondas and keep the cyl ture because of the open deck setup. Though it might be a sleeve walking but that makes no sense, or does it???
 
Got around to pulling the head and the piston pin on the #2 cyl was rubbing the cylinder wall, but only on one side and it turns over easy.
how does that happen?
The engine didn't smoke hardly at all and compresion was 155 hot and 185 w/ tsp of 30wt rest where 200.
The shop that rebuilt it is gonna take care of it but has a 1/4" groove in the cylinder wall. is there a fix for that? lol

:puke: :puke: :puke:
 
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