Early piston slap?

[911 dreamer]

Hi people, please can you have a listen to the video attached. This is my 1998 c2, i spent £4.5k on an engine rebuild after the ims started to break up (caught in time luckily), then a couple of months later it starts making this noise when starting from cold. In the video it hasn't been started for 3 days and as you can hear the noise goes away after less than a minute. The indy has told me it's early piston slap and will cost about £6k to put right!

 

It didn't do it before and i wonder if they've put different oil in it or something. Any ideas please? 

 

Thank you.

 

 

 

[flatjoe]

Hi. Also water pump can do the mess if got play on shaft. Try...

[911 dreamer]

Water pump's not long been done flatjoe, thanks though

[JFP in PA]

I would try starting the car briefly from cold without the serpentine belt on it to see if the noise goes away.

[911 dreamer]

Good thinking, I will try and report back, thank you

[911 dreamer]

I haven't tried starting without the serpentine belt yet but I have changed the oil to DT40, unfortunately no change, will try removing the belt and come back.

[Ahsai]

Also check your cats. Use a mechanic's stethoscope or a long screwdriver. Loose elements can knock around inside.

[Schnell Gelb]

Listen carefully as close as you can get to each rear wheel. Which is worse?

With the car up on a lift, use a listening device - preferably a Steelman Engine Ear to listen to the worst side. Move all along the crankcase from close to the crankshaft all the way to the Camshaft cover. Do this for each cylinder on that Bank.Which is worst and where on that cylinder is the noise the worst ? Listn ,not just for volume but for additional little extra rattles ,thuds,and knocking .Be evry methodical.Make notes on a diagram showing each cylinder.

This way we can give you a better diagnosis.

Consider getting a UOA from Blackstone,Caterpillar or alternatives.

It may be a noise you can just live with for many thousands of miles with good lubrication and careful monitoring ,so don't despair. But do gather great data !