( .Y. )
VR V8 knock and squeak from rockers? (with video)
Yeah my day just got real bad. I went to warm up my ute this morning and it started to make a squeaking sound. I popped the bonnet and was about to tighten the belts when I noticed it coming from the rear of the left bank. I removed all the belts to be sure and I still get the sound.
There is an obvious squeal and even worse a knocking noise. Pretty sure I have done something terrible. The video isn't to long because I didn't want to cause any more damage but you will differently hear what im on about.
Please help.
I'm pretty sure its a throw away job
vr knock. - YouTube
Last edited by 304runner; 14-08-2011 at 11:12 AM.
sounds like a broken rocker to me, maybe a broken push rod as well. when it was running could you here it not firing on all cylinders?
Donating Member
sounds weird but couldn't distinguish what it could be, i think you need to have someone hear it in real life instead of thru a vid.
( .Y. )
Well funny you say that, yesterday when I moved it onto the grass to wash it a mechanic mate said it sounded like it was missing an I told him it was just cold. I took the rocker cover of again this morning and nothing looked out of place.Originally Posted by Shooter 88
I removed the two rockers closest to the firewall where I think the sound is coming from and pulled out the push rod which were fine and both had clear ports.
Can a dodgy spring make this sound?
Donating Member
i had issues with a set of yella terra street terra st-2032's
one pair had excessive sideways movement you could only see when engine was running.
not sure what rockers you're running but maybe have it run and idle with the cover off and observe where the noise is coming from.
( .Y. )
Yeah noob question, but is there a way to do it so oil doesn't piss out everywhere?
Donating Member
at idle it doesn't piss everywhere, a couple of mins idleing should be ok
rev it and you'll make a mess!!!
in the past when i used to adjust rockers the "wrong way" i used to pull a few revs so i made a sheild out of ice cream containers.
but like i said at idle, you shouldn't make a mess unless your oil pressure is way high
( .Y. )
Yeah sweet..
I gave it a blip to hear the knock and squeal sound as you cant hear it at idle so a little bit comes out from the push rods. They all seem to be moving as per usual so Im stumped?
Valve stem perhaps?
Donating Member
when my shaft mount rockers were stuffed the pushrod was hitting in the head so that may account for the knock but not the squeal.
I wonder if you have a burr in the lifter bore and it's not rotating on the cam lobe as it should
seem a deeper problem than first thought
( .Y. )
well ages ago we replaced the lifters becuase they were knocking. Upon further inspection we noticed one of the cam lobes was chewed out. We didn't replace the cam but intend to do it soon, so in went the new lifters. The lifters are playing up again and have been for a while. Not sure if this gives you any other thoughts?
Usually you will need to replace both the cam and the lifters together as they both wear in together from new, which basically "work hardens" the running areas on both the lifter and the camshaft lobe faces. If a new cam is installed with old lifters, or new lifters installed with an old camshaft, then the engine will most likely end up having reliability and lifter/cam lobe wear issues. Both the camshaft and lifters have to be replaced as a set.
Also when running in a new engine or new cam and lifters, the engines revs should be varied and the engine should not be held at any one certain rev range for any length of time until at least 1000,k's have been done and an oil change and filter been done. Then the cam and lifters will have the best chance to last their normal service life. Around town type driving conditions is perfect for running in a new cam and lifters or a new/reco engine. Highway driving where one certain rev range is mostly used, is not recommended for running in a new/reco engine or cam etc.
Last edited by Brett_jjj; 14-08-2011 at 03:19 PM.
( .Y. )
So it could be the cam slapping on a stuck lifter maybe?
Donating Member
you said you replaced lifters but also mentioned the cam is worn...
me thinks the lifter has worn in (bedded in) but the worn lobes on the cam have gotten worse after bedding in to the new lifters...
me thinks you need a new cam and lifters in one go
if you're strapped for cash, i have a standard cam you can have for 25 bucks (i reconmend this as only temporary solution for you untill you get a new cam and lifters)
( .Y. )
Yeah I have a standard cam here from another engine im stroking. The engine has pretty much had it so I always intended to rebiuld or replace it at the end of the year when I had some spare coin. Just didnt want to pull apart the engine to replace a cam without doing everthing else at the same time. Cheers for the heads up
( .Y. )
Is it at all possible to replace the cam without taking the engine out? Got a mate who has a new cam and lifters he's going to give me providing I buy him a new set late on. I'll replace the cam and lifters but figure I'll replace the head also. Got a spare head on the work bench at the moment.
( .Y. )
[update]
Ok so I pulled off the head and I found that area of the head for cylinder 8 was wet with fuel? So im assuming an injecter was stuck open and cleaned the bore of oil and caused it to squeak and squeal... As for the knocking sound...well I have no idea... Im going to throw this other head on just incase.
Can logged out rings cause a knocking sound?
Donating Member
it's possible, without oil to lubricate the rings they may have worn prematurely and the the knock could be piston slap.
( .Y. )
Well you[r] 100% right... I replaced the injector after fugging around replacing the heads and gaskets ect and all is good bar the slap noise but Im willing to live with it. I'll post up another vid soon...
Talk about going about it the hard way to replace an injector.
Thanks heaps to everyone that had an idea. I would have throw a match at it if I didn't get any advice for you JC members.
Last edited by 304runner; 15-08-2011 at 09:52 PM.
Donating Member
try thicker oil and lucas oil stabilizer, might reduce the knock and keep the engine together a bit longer while you build another one.
all the best dude
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