Hi everyone,

 

been lurking for a while, first time posting.  I've been working away on my Octavia (BXE engine, 109k miles), and am beating my head against the wall at the moment.  Opinions, ideas, and "you're an idiot" all appreciated.

 

Engine started making a tapping sound and misfiring on a road trip.  Took it to a few mechanics, they all listened and told me it wasn't worth me paying to have it fixed, the engine was toast.  So I decided there wasn't much to lose, I'll have a crack at it myself.

 

Don't have a video of the original noise, but it was basically this:

 

After a bunch of reading, suspected worn camshaft, so popped off the valve cover and no surprises, one of the lobes was worn right down.

 

Ordered an Estas/GT camshaft kit, including lifters, from Lymm (mega helpful guys), got it all in, started her up, have run in the camshaft for 20-30 minutes at 2k rpm.  Also while things were apart I popped off the sump, cleaned out the filings from the old camshaft, cleaned out the pickup and verified that the oil pump looked ok and the chain had tension.  Spun the engine over and looked at the crankshaft, but didn't pop off any bearing caps.  Put in a new oil filter and oil (507.00, so a bit lighter than the old oil), ran it for a minute with the cover off to verify oil was getting to the camshaft (it sprayed oil everywhere so I guess it's getting up there).

 

Anyway, things are not working as I would hope.  Have the same tapping as before, but it is LOUD!  Holy crap.  I've run the engine for 20-30 minutes at 2k rpm with no improvement.  I know that the hydraulic lifters take a while to pump up, but I wouldn't expect this level of noise, feels like I'm driving a tank.  I wonder if anyone has had something similar, and has any advice?

 

My plan once I can get back to the car (bogged down with work atm) is to run it with the aux belt off to make sure it isn't something else, and perhaps to take off the cam again and make sure the lifters/oil galleys aren't blocked?  (regretfully, I wasn't that careful about this when I put them in).  Replacing the stretch bolts again is a drag though.

 

I didn't do any priming of the lifters, just put them in and let them bleed down, which I gather is fine.

 

Mistakes I have made: (1) don't own a fault code reader, (2) don't own a pressure gauge, haven't done oil pressure or compression (no oil pressure light though.  I'm trying not to throw any more money after this.

 

Thanks chaps.

Tom

Neglected to mention that it is also running rough, revs occasionally drop slightly with constant accelerator, doesn't like idling.  I assume that this is because the timing is a little off (the pins go in (just), but I haven't looked at the torsion value, again no fault code reader...)

Did you ever diagnose the original issue? The camshaft way just be a symptom - eg was the original issue oil pressure related causing "Engine started making a tapping sound ". If so now you have new camshaft, tappets/lifters etc if there isn't enough oil pressure it won't manage to fill the new hydraulic tappets. I think you need to measure oil pressure. You mention oil chain had tension - but was the oil pump actually operating correctly.  Did you check pickup pipe?

 

Also cam shafts don't usually "just fail" but the will gradually wear out for whatever reason unless there has been another catastrophic incident. 

 

Any other things to consider, any recent work - even if it seems unrelated? Any other symptoms eg smoke before / after the issue? How did the drained oil smell? - after a major oil pressure incident where big ends/mains are involved it take on a cream crackered distinctive smell. 

 

 

Edited 19 October, 20214 yr by bigjohn

Thank Big John,

 

Sounds like good advice to measure the oil pressure.  I decided to ask a mechanic to come out and run all the diagnostics I don't have tools for (oil pressure, comp, etc), hopefully that'll happen soon and I'll report back with findings.

 

The pickup pipe is clean - I took it off and cleaned it out.  No catastrophic incidents, no smoke, no unusual oil smell.  Car had the T-belt replaced around 100k miles, I bought it around 107k, now it's done 109k. 

 

I wonder if a filing from a gradually failing camshaft could have worked it's way in and blocked oil to a lifter...

 

Planning to take the cover off again this weekend and verify that the lifters are not pumping up, just to make sure I'm not barking up the wrong tree.

 

Tom

any more news or have you given up on it

 

Mine sounds same,what could be problem