Urgent - Opinions Needed!

[Cameron 16]

I need a bit of help diagnosing a tapping noise coming from the top end, or at least some help in deciding weather its worth me pulling an all-nighter to fix! My mapping session at Emerald is tomorrow morning, I've spent today swapping the cams over (from standard to my reground Newmans) and I have started it up to find the top end is tapping.

 

I've done a compression test, all cylinders are 240psi as they have always been, and all get there nice and quckly.

I've tried taking the rocker covers off and seeing if I can compress any of the lifters by hand (while the cams are round to fully closed) and I can't seem to be able to. The symptoms seem to point to a sticky follower (hydraulic) so I'm going to try and whip them out, take them apart, drain them and get them back in tonight.

 

Here's a video of the horrible noise:

 

 

I really hope its fixable as I don't want to have to wait for yet another mapping session!

[welshpug 1,666]

hard to say exactly what it could be, definitely head/cam related not injector, and seems to be only the one tap not several.

 

 

could be a tappet as you said, as its quite audible it should be easy enough to trace at least which cylinder its coming from.

[Cameron 16]

It sounds like its coming from No. 4 (flywheel end), I've tried the extension bar to the ear trick but I can't trace it as its quite loud and my hearing is quite rubbish. I'm starting to take it apart now, hopefully the problem will make itself apparent without me having to go taking the head off.

[EdCherry 34 1 Cars]

It sounds like its coming from No. 4 (flywheel end), I've tried the extension bar to the ear trick but I can't trace it as its quite loud and my hearing is quite rubbish. I'm starting to take it apart now, hopefully the problem will make itself apparent without me having to go taking the head off.

 

Cant comment on the problem but goodluck! Always great fun pulling a late one to get things finished.

Edited August 10, 2009 by EdCherry

[Anthony 1,003]

You have run it on fast idle for a few minutes to let the lifters pump-up, haven't you? I'd do that before pulling it apart, as the valvetrain will make a racket until the lifters pump-up and close up the valve clearances properly. Also, if they're new cams, FFS don't let it idle until you've bedded them in properly!

[Paul_13 212 1 Cars]

Doesnt it burn them out or something if you leave new cams in and let them idle?

[Cameron 16]

Anthony - don't worry I ran them in, 20 mins @ 2500rpm. They're still making a racket though!

 

I didn't de-pressurise the lifters when I swapped the cams, so I'm hoping it could be something simple like that. That said, if a valve was sticking open then the compression would be down on that cylinder.

[welshpug 1,666]

flywheel end pot is No1 its bloody French

Edited August 10, 2009 by welshpug

[Cameron 16]

Really? I thought flywheel number 1 was "normal"?

 

Just putting it back together, fingers crossed.

[EdCherry 34 1 Cars]

Really? I thought flywheel number 1 was "normal"?

 

Just putting it back together, fingers crossed.

 

Nap its those bloody french that like to confuse people.

 

Hope its stopped! goodluck cam!

[Cameron 16]

Its running! It doesn't sound like it has the death tap either, but I can't run it for long enough to find out with it being gone midnight. Will be up early tomorrow to test it out, but it doesn't seem to be anywhere near as ridiculously rich as it was, despite being on the same map.

 

Everything crossed for tomorrow morning!

[DrSarty 90 1 Cars]

Good luck Cam.

 

Yep: cyl 1 "is at the f*cking flywheel end" (that's how I remember it). (Really all those 'F's should match with 'four', but it's the opposite!)

 

You did mention the 2,500rpm bed in that you did, but that was on the original Newman (lumpy) cams. Did you re-do it on the regrinds? Dunno if that'd make any difference; but at least it's all calmed down a bit now.

 

What I'm intrgued to see/hear is whether the new regrinds are any better or worse than the standard GTI6 cams.....Cam.

 

Best of luck.

 

Rich

[Capn. Pugwash 0]

I had a tappy top end too- turned out the bolt holding the camshaft retainer had worked loose and was bashing on the edge of the cam lobe on every cycle! It ended up looking like a banana!

This was on the first day of a 6 day tarmac rally so there was plenty of late night action....I don't think I got to bed until the early hours that night!

[mechanicalrepairs 8]

Have you double checked the timing on this, i have had them sometimes when the timing is ever so slightly out, reset it and it was fine then, this was when fitting a set of camshafts too.

 

Hope it all goes well at the rolling road session, the best i got from a cuctomers with a set of cams and a btcc inlet manifold was 212 bhp, quite impressive despite the rest of the car was standard.

 

Carl C.G.Cars Leicester

[Cameron 16]

That's a pretty good result!

I'll be happy with 190bhp and a decent torque spread, it was making 176bhp on standard cams.