Please Help! Loud Knocking/Grinding/Tapping after rebuild

edbutler

Hey All, Please Help!

Following a Cylinder head refit, New Timing Chain Kit, new V-Belt and Secondary Chain Tensioner fitted (the old one broke)....

Ive now got a very loud knocking coming from the right hand side of the engine (timing chain side). Externally its rather loud and it has got worse since the car was built up. Externally it sounds like a knocking but inside the car it sounds like a chain clattering. It is LOUDEST from the O/S Rear wheel arch.

When being driven, at say 1500rpm in 5th Gear and neutral engine load, it is virtually silent... Lower gears (1, 2, 3) its much louder and especially loud when rolling down a hill with engine breaking, and sounds like a constant chain on metal sound...

Ive checked the valvetrain under the rocker cover and all is beautiful and clean. Had a look at the timing chain and there seemed to be no excess play and prodded the tensioner to make sure the garage did that part... they did. This leaves me to think its the Seconday (Balancer Shaft/Water Pump) chain.

Please please could any of you expert techs shed some light on this... Could a knock this loud be a slapping chain...? The engine didnt make a peep other than a little chain noise literally 1 mile before the work.

VIDEO OF THE NOISE:
https://s66.photobucket.com/albums/h274/ ... =Movie.flv

Cheers!!

JohnnyN

Sounds almost like the chain is fouling against the cover? That sounds like it needs stripping down again unfortunately.

edbutler

Thanks for your quick reply mate, confirms my suspicions...

Ill get in touch with the garage and hope they will warrant the fix... They have probably fitted the secondary chain tensioner wrongly 🙁

edbutler

Anyone else any input? Is it plausible that one of the chains hasnt been tensioned properly and how easy is it to mess up? 🙁

DaFlyinSkwirl

if all they did was swap out the head the secondary chain shouldn't have been touched.

what was the work done to your car?

I have managed to break the plastic guide that is where you prod the chain to expand the tensioner. if that is broke, you could be hearing pieces of plastic hitting the chain.

if thats whats wrong, the worst case is that there's more likely than not plastic bits in your oil pan which is never good, not to mention you'd have to release the tensioner to replace that guide.

if you can pop the cam cover off, use a flashlight and look very carefully at the long swept guide thats under the exhaust cam gear and make sure it isn't damaged. its hard to tell so look very closely.

the secondary chain tensioner is a very small hydraulic plunger. it is possible it could have been reinstalled incorrectly but I say check the guide where the main tensioner pushes first.

edbutler

DaFlyinSkwirl said:
if all they did was swap out the head the secondary chain shouldn't have been touched.

what was the work done to your car?

I have managed to break the plastic guide that is where you prod the chain to expand the tensioner. if that is broke, you could be hearing pieces of plastic hitting the chain.

if thats whats wrong, the worst case is that there's more likely than not plastic bits in your oil pan which is never good, not to mention you'd have to release the tensioner to replace that guide.

if you can pop the cam cover off, use a flashlight and look very carefully at the long swept guide thats under the exhaust cam gear and make sure it isn't damaged. its hard to tell so look very closely.

the secondary chain tensioner is a very small hydraulic plunger. it is possible it could have been reinstalled incorrectly but I say check the guide where the main tensioner pushes first.

Cheers Skwirl! i recognise you from EcotecForum, welcome to this side of the pond!!

Yeah i have no idea why they fiddled with the Balancer Shaft chain but they said the tensioner was broken to fitted a new one. I indeed think that a guide could be broken as you said or the tensioner was fitted incorrectly... Ill hopefully have it looked at very soon and not driving it for now.

Am i right in thinking that a noise like this shouldnt be the timing chain!? The timing chain surely turns a lot more pressure (the valvetrain!) and would have slipped if it was so loose wouldnt it?!

EDIT: Sorry forgot to mention, i checked the main tensioner and guide by removing the rocker cover and it seemed ok from there, its very dark down there tho!!

DaFlyinSkwirl

hey ed 😃

believe me its easy to break a guide because I've done it not too long ago. I pushed the tensioner and thought I didn't expand it so then I hit the end of my long screwdriver with a hammer and heard a nasty crack sound and man did my heart sink when that happened..

it was hard to tell from the top but i could see some of the orangish plastic was missing so I removed the guide from the lower timing cover and it was smashed up pretty good. luckily i had a replacement lying around.

also check that the upper guide is in place and tight.. the one that sits in between the two cam gears.

edbutler

Thanks again Skwirl, will probably get to take a look next weekend all being well...

Pics and updates to come...! cheers..