loud engine knocking

[nalchlan]

hey guys my engine has started to make a fairly loud knocking noise, it happened right after a little powerskid (private property ofcourse) and after a lot of searching im still stumped

it happens from 2000-2500 rpm and i can hear it continue well into high 3000rpm and after that i cant hear it over my exhaust when driving, and im not too keen to try it to a higher rpm incase it makes things worse. it happens with the clutch pedal down so im 99% sure its coming from the engine. also, engine is quite reluctant to turn over when hot

extra info i thought id add in;
219 000k's motor. I have 1.98 ratio rockers, but ive had the cover off both sides, checked the torque and looked around all seems ok, noise is no less or no more with the rocker cover off. oil was changed as was filter november or december last year since then has done probably 6-8000 km's on that oil, car has a slight oil leak but the oil looks fine. two diesel mechanics have told me big end and one of them said posssibly injector aswell

thats all i think i can add any opinions or advice would be greatly appreciated

 

[vscaprice98]

ok to rule out ur injectors unplug one at a time bud if it shuts up then u know it a injector
im leaning towards bigend knock but the revs are getting me
im thinking in me head atm that u could have a crack in a piston and getting a gudgen knock at higher revs which could break apart it hard tosay with out hearing it though

 

[nalchlan]

yeah im not very suspicious of injectors but why not haha, and how would a big end problem behave rpm wise thats different to my problem? my first thought was gudgeon noise too... if youre clueless im sure i could upload a sound or video clip onto youtube cheers for the help mate.

 

[vscaprice98]

a big end will norm constant knock and clatter worse at higher rpm u can spin a main bearing which is ur main caps and can come into effect in to revs and norm u find it more of a popping noise than a knocking noise i was and thinking of gudgeons going with the revs with a knocking noise at higher rpm i lost track of how many motors i had let go when i was racing speedway in couple differnt grades i use to race in but if u want to upload it mate u can if u want

 

[GothicKidd]

Isnt like YouTube - Yeah is it? If it is... Your engines ####ed... sorry
I gained a knocking noise after sitting on the limiter.. it turned into a ####ed engine.. Mechanic said my engine is rooted and I needed a new one.. and that was before It stopped worked..

 

[nalchlan]

no i hope i dont have that same problem... i reckon that noise is more dull, my sound is more of a sharp rap compared to that if it were a knock. it also doesnt have it while idling. only from 2000-2500 upwards. i will somehow get my sound clip onto youtube tonight, thanks for the reply

 

[nalchlan]

bit of an update: noise is still made with drive belt off so i guess that rules out water pump or any other belt driven accessory being the problem

 

[nalchlan]

so i took off the heads today, and depsite their being an ancient looking bit of buildup on the heads the bores had scratches that were parallel and made it look almost like its had a hone/bore out recently... only small sections still have the scratches, others are smooth. almost as if the scratches are in little depressions in the bore, recent rebuild or is that normal?

 

[vscaprice98]

honing marks wouldnt be causing ur knocking at certin revs take a photo of ur bores bud and post em for us while ur heads are off how much movment is in ur pistons if u got a spun bearing u can sometimes push down a bit on the piston and u can have a bit of movment out of it as well u norm would have a little bit of gudgen movment with ring movment but not alot if it is good

 

[calais24/7]

Isnt like YouTube - Yeah is it? If it is... Your engines ####ed... sorry
I gained a knocking noise after sitting on the limiter.. it turned into a ####ed engine.. Mechanic said my engine is rooted and I needed a new one.. and that was before It stopped worked..

ohhh how that noise sounds so frustratingly similar, vn skid car did it, i wonder why though :S