11 replies to this topic

[adcyork]

I've reconnected my engine back up and started it up today after putting it back in. While it was out i replaced the single line timing chain for a budget duplex set from minispares. Now i've started the engine up i can hear an intermitent knocking and tapping at idle which seems to stop as the revs raise.

When i fitted the duplex chain and gears i countersunk the 2 bolts and used the countersunk screws. I also flattened the round raised piece on the timing cover that it tells you to do in the instructions with the gears. I was unsure wether to fit the tensioner or not so i called minispares and they said that it isn't needed on a duplex set so i didn't fit it.

Here's a link to a video i took that the noise can be heard on: http://smg.photobuck...=video-0010.flv

has anyone got any idea what's causing that noise? I have a sneaking suspicion that it's that timing cover that is catching but i did turn the engine over by hand on the pulley nut to check wether the chain and gears rubbed at all and i couldn't feel or hear any rubbing of any kind at all which then makes me doubt thats the cause.

Edited by adcyork, 06 January 2007 - 11:25 PM.

[miniboo]

i reckon it could be that the countersunk screws aint countersunk enough maybe?

[Big_Adam]

You mean the big tappety noise or the sound that is akin to somthing rumbling about?

[adcyork]

i reckon it could be that the countersunk screws aint countersunk enough maybe?

nah i don't think its that as i did countersink the screws really deep and i checked for clearance on them when the chain and sprocket was fitted and it was all clear.

You mean the big tappety noise or the sound that is akin to somthing rumbling about?

yea big tappety noise.

[Dan]

If it was catching anything it would get worse at higher speeds, not better. It does sound like something knocking but it could be the lack of a chain tensioner. That would improve at higher speeds.

[Sprocket]

Was this on an A+ cover??

Did you hammer flat the indent at the very bottom where the silly useles bracket is on the out side??

Guess how I know

[adcyork]

ooo nasty! yes it is an A+ cover and as i said in my first post yes i did flatten the round piece down. Athough thats all i can think it would be. maybe i haven't flattened it down enough??? I made it level with the surrounding piece of the cover and so i doubt it's possible for it to be rubbing on that. anymore ideas people?

[chriszxr750]

anymore ideas people?

i suppose it sounds silly but you did line up the timing marks probably??

easy not to if you still have the inner wings there.

other than that check the engine mount radiator etc, and the fan, making sure thats its not rubbing /on right way round.

sorry if thats sounds patronising, but it silly things like that, that gets over looked.

[koss]

Try a bit of plastic tube in your ear about 2 foot long and with the other end see if you can hear where the noise is exactly.
Sounds like a valve to me.

[Guess-Works.com]

does the timing cover have a breather and did you remove the sort of flange which is around the breather on the inside of the cover... they are notorious for catching the cam gear on the duplex.. also the fans not clipping anything...

As for the tensioner, I've never used one on duplex being an A Series biggot ( rather than A+ ) and never had a problem with noise.

[adcyork]

thanks for the advice gents. It's all sorted now! turned out it was the damn round pressing that i hadn't made flat enough! There was only a fraction in it but it still just caught on it at low revs when the chain was able to flap about slightly. anyway all sorted now. cheers

[fikus01]

word of advice i think your tappets need adjusting too!! 12 thou if its a 998 or std 1275