I has a problem - knocking

[EVOCPE]

What are you thoughts?

And dont worry, im not drivin the car around

Its a forged bottom end, no balance shafts, OEM EVO2 crank, ACL Comp bearings all round

It sounds like its coming from the head, but i cant see anything wrong with it when i removed the tappet cover, all rockers are there, i turned the motor to make sure all valves raise and drop, it hasnt skipped a tooth

My oil pressure sits on 85psi when cold and 15psi once warmed up

Yes there is oil in the engine, Penrite HPR10 10W-50 Full Synthetic

Dont mind my ugly mug

http://www.youtube.com/watch?v=BeHial5qZ6M&feature=g-upl

 

[BMGTZ]

bent exhaust valves...

sounds the same as the 6 bolt I just pulled the head off. No skipped teeth but all exhaust valves bent.

I expected to find big marks on the pistons.....but none there. It even still had compression.

 

[EVOCPE]

Wouldnt i know if they are bent by turning the engine? coz all the valves move in and out good, plus the car drove fine

 

[robevo]

ouch, thad doesnt sound too good.Sounds stupid but have you checked engine mounts etc

 

[EVOCPE]

Im using Prothane solid engine mounts all round, all seem to be still there

 

[EVOCPE]

Also i'll add that when the car is on idle the sound isnt there, also its not there on high rpm, its only around 2-3k rpm

 

[EVO-00X]

I thought it was valvetrain related too when hearing it on the video because there's a distinct higher pitch rattling sound, much like you get when you have a stuck lifter, give it a rev and it disappears.
I got him to check that all the cam caps were tight and that the roller rockers werent damaged or not seated properly.
Then we spoke a short time ago and I heard the bastard noise over the mobile phone and its completely different to the noise in the video.
Its a loud knocking sound and sounds worse, like something slapping about in the bottom end.
When this engine was OEM straight from the frontcut, it failed due to crankwalk and a spun big end.
Then we rebuilt the motor with a replacement EVO 5 crank and forged rods and pistons... would be insteresting to see what the cause is this time.
Time for Mikey to check the oil for metallic shit. The boys who have heard it in person are suspecting the dreaded 'Evo' big end bearing curse has struck another victim.

 

[khubner1]

binding valve spring coils?
your running some pretty wild cams atm arn't you?

how the valve piston clearance. all things you've probably already though of but i thought i'd mention

 

[ENGINR]

Rip it out and pull it down. Only way to be sure :thumbsup:

 

[EVOCPE]

Narrowed it down to be @ #2 cylinder by removing the spark lead off the engine while its on and the noise will disapear, every other cylinder it would still be there

So im assuming now it could be a conrod bearing or gudgeon pin.... i'll be rippin the engine out soon as i get an engine crane and diagnosing it further

1 thing i do know is im gonna get myself a forged crank while its back out

 

[CYBORG-X]

possibly droped a piston skirt...
pull the motor out, take rocker cover and sump off and watch the motor turn over first... shouldnt have to remove the head to find the problem

 

[EVOCPE]

Nah wont be removing the head unless the problem cant be seen

I should know if i dropped a skirt coz parts should come out when i drain the oil or see it when i remove the sump

 

[CYBORG-X]

you can see it once you remove the sump, i had a pootrol that cracked a whole skirt off but sat there comfortably till i pulled the piston out...

 

[CYBORG-X]

wait, does the engine have any piston or bore oil squirters??

 

[EVOCPE]

Yes it does, it has the standard oil squirters

 

[CYBORG-X]

hmmm... id remove them, the crank brgs need all the oil it can get. but thats a different chapter of the book... but it definatly sounds bottom end-ish

 

[blackvr]

Gudgeon pin circlip dislodged and the gudgeon pin rattling on the bore wall ?

 

[EVOCPE]

Engine should be out in the next few days, so will let you guys know

 

[EVO-00X]

 

[EVOCPE]

Here is the outcome

Crankwalk

Bye bye bearing, hello gravy & onions