« previous next »
Pages: [1]

Author Topic: Sounding tappy/knocky but is not the bottom end, Piston slap?  (Read 1423 times)

Offline 6foot6

  • Not said much yet
  • **
  • Posts: 93
Sounding tappy/knocky but is not the bottom end, Piston slap?
« on: 13 July 2010, 15:23 »
Im normally good a engine noises, but my Golf is getting the better of me.
It sounds like a bottom end knock, but when I have had bottom ends go before , they get worse when revved and sound like a London Taxi.

at Tickover I can hear this knock (its always been there since I got the car 2 years ago , but sounds a little louder now) it goes away when revved and if I give her a good blat  and get the oil nice and hot really gets rid of it on tickover.

I have a early Digi 8v on a E plate, this should have hydrolic tappets so I am going to do a Oil Change tomorrow and see if its better (its due one) other than that any thoughts? Piston slap, tappets just old and loose its done 170,000 or big ends going?

Pulls like a train in any gear and has no running issues. :undecided: :cry: :drool:
Logged
Golf GTi 8v Alpine white - Project track shlag - TLC needed - KnN/Scorpien full system oval tail pipe, rust here and there.
1991 Toyota MR2 MK Revision 1 Turbo, rev 3 LSD, CT20b Turbo, HKS Exhaust, Blitz Downpipe 244HP@the wheels @ 13psi - 12.9 SQM :D
1994 BMW 730 V8 fully loaded 220BHP

Offline rob.043

  • Here all the time
  • ****
  • Posts: 496
Re: Sounding tappy/knocky but is not the bottom end, Piston slap?
« Reply #1 on: 13 July 2010, 22:10 »
The symptoms sound the same as my worn tappets prior to replacement. Was loud on a cold start at tickover, then reduced or disappeared when warm. Its certainly a more common problem than piston slap (as far as my experience goes), and I've never done a bottom end to know the sound of that....

Good opportunity to do the valve stem oil seals too, if there is a bit of oil consumption. I replaced my tappets, but they can be dismantled and cleaned, which although time consuming, is cheap! I saw a good how to on Ben Lessani's project thread...
http://www.golfgtiforum.co.uk/index.php?topic=49436.msg886430#msg886430


Logged

Offline Steve_B

  • I live here
  • *****
  • Posts: 661
Re: Sounding tappy/knocky but is not the bottom end, Piston slap?
« Reply #2 on: 14 July 2010, 13:39 »
Could be worth checking your exhaust manifold isn't blowing due a crack, or one of the gaskets failing.
Logged

Offline mk2bal

  • I live here
  • *****
  • Posts: 811
Re: Sounding tappy/knocky but is not the bottom end, Piston slap?
« Reply #3 on: 14 July 2010, 17:19 »
dont you only get piston slap from forged pistons on startup due to the rate of expansion been slower than normal cast jobbies? i aint saying that gospel its just what my bosses evo suffers from now its all fully forged and didnt happen before..
Logged

Offline mwep201081

  • Here all the time
  • ****
  • Posts: 356
Re: Sounding tappy/knocky but is not the bottom end, Piston slap?
« Reply #4 on: 14 July 2010, 19:46 »
Quote from: mk2bal on 14 July 2010, 17:19
dont you only get piston slap from forged pistons on startup due to the rate of expansion been slower than normal cast jobbies? i aint saying that gospel its just what my bosses evo suffers from now its all fully forged and didnt happen before..

and worn rings/bores
Logged
Pages: [1]
« previous next »