Piston slapping
Author
Discussion

Gatesy26

Original Poster:

5 posts

204 months

Monday 9th November 2009
quotequote all
Has anyone experienced similar problems or can advise on what would be the best course of action? I have owned my 56 plate Monaro LS2 for 3 years now, 10 months ago Vauxhall replaced the engine due to excessive Piston slapping but for the last month I have started getting the same problem again, I have only covered 5k miles with the new engine and its slapping for about 5-10 minutes from cold. Vauxhalls are now saying it is quite common and are not interested. The car is still under warranty for a few more weeks. Thank you to any advice in advance.

Phantom Mark

257 posts

207 months

Monday 9th November 2009
quotequote all
I reckon my LS3 in the R8 is slapping like biach when cold as well.....done it from new, got 3k on the clock now, awaiting a definitive opinion when I go down to see the guys at Monkfish for its service.

Boosted LS1

21,200 posts

291 months

Monday 9th November 2009
quotequote all
It was certainly a common issue with earlier engines but didn't cause any damage as far as GM were concerned. Some people got replacement engines and some didn't. It probably came down to how loud the slap was and how loud you shouted at the dealer. Current engines have skirt coatings on the pistons so should be able to run with a slightly tighter piston to bore clearance, ie less slap.

Have you tried a slightly thicker oil that's still within the correct specification? I don't know if it would work but I'd give it a go.

Gatesy26

Original Poster:

5 posts

204 months

Monday 9th November 2009
quotequote all
Cheers Boosted, I'll certainly give that a go. Its back in the service centre on wednesday for an oil change.

TheEnd

15,370 posts

219 months

Monday 9th November 2009
quotequote all
I did hear an idea that piston slap in US based V8's was do to the conrod/wristpin geometry, and many euro engines have them slightly off set to keep them loaded up.

It's certainly shocking that it's still occurring in this day and age. I guess Vauxhall will add piston slap to "acceptable behaviour" and let it stil until you are out of warranty, and the more severe symptoms start.

petrolzed

182 posts

227 months

Monday 9th November 2009
quotequote all
How do you know you have piston slap?
I have a new LS3 VXR8.

Gatesy26

Original Poster:

5 posts

204 months

Monday 9th November 2009
quotequote all
I get a tapping noise from the top of the engine from cold. It slowly fades away as the engine warms up. + Vauxhall have told me thats what it is.

monkfish1

12,458 posts

255 months

Monday 9th November 2009
quotequote all
This is normal, assuming its not excessive. The piston skirts are teflon coated to reduce it, but over time it weears away and it does become noticable, especially as you put the engine underload. Nothing will happen. Niether can you eliminate it.

However, if you hear an noise which is just one cylinder, thats a different matter.

Gatesy26

Original Poster:

5 posts

204 months

Monday 9th November 2009
quotequote all
Well mine sounds very much like it is coming from just one cylinder. Is this a problem?

monkfish1

12,458 posts

255 months

Monday 9th November 2009
quotequote all
Gatesy26 said:
Well mine sounds very much like it is coming from just one cylinder. Is this a problem?


If one cylinder is louder than the rest, that would logically suggest an issue. Without hearing it, is not really possible to say, but if i heard it, then yes i could offer an opinion.

Boosted LS1

21,200 posts

291 months

Monday 9th November 2009
quotequote all
A lot of information's here:

http://www.pistonslap.com/photos.htm

Gatesy26

Original Poster:

5 posts

204 months

Monday 9th November 2009
quotequote all
Ok many thanks, depending on how my visit to Vauxhall goes on wednesday I may well be bringing over to you Monkfish.

monkfish1

12,458 posts

255 months

Monday 9th November 2009
quotequote all
Gatesy26 said:
Ok many thanks, depending on how my visit to Vauxhall goes on wednesday I may well be bringing over to you Monkfish.


No problem, just bear in mind we really need the car overnight to make a meaningful assesment.

S800VXR

5,877 posts

231 months

Monday 9th November 2009
quotequote all
Wish mine had just been piston slap! smile

doleboy

747 posts

248 months

Monday 9th November 2009
quotequote all
S800VXR said:
Wish mine had just been piston slap!


Aye. Wasn't just one either

Trailermasher

730 posts

253 months

Monday 9th November 2009
quotequote all
S800VXR said:
Wish mine had just been piston slap! smile
Ditto, although the initial noise was similar. frown

Harryoz

1,016 posts

256 months

Monday 9th November 2009
quotequote all
Trailermasher said:
S800VXR said:
Wish mine had just been piston slap! smile
Ditto, although the initial noise was similar. frown
Double ditto!!

Bonnie and Clyde

11,701 posts

223 months

Tuesday 10th November 2009
quotequote all
Harryoz said:
Trailermasher said:
S800VXR said:
Wish mine had just been piston slap!


Ditto, although the initial noise was similar.


Double ditto!!
I know Harry thats shit news

crisisjez

9,209 posts

236 months

Tuesday 10th November 2009
quotequote all
Soph got pissednslapped me.....does that count hehe

Bonnie and Clyde

11,701 posts

223 months

Tuesday 10th November 2009
quotequote all
crisisjez said:
Soph got pissednslapped me.....does that count hehe
roflroflrofl