Why no whine?

JonT · 08-11-2002, 08:59 AM

The only thing I miss from my 3.0 is the turbine like whine that it used to make. Why does the 3.6 seem so quiet compared to the 3.0? Is it just they were engineered to be quieter?

BlueSkyJaunte · 08-11-2002, 09:23 AM

I can't help you there, but at least I now know I'm not the only with a 3.0 that whines.

Fan design? Bearings? "None of the above"?

aseem · aseem's Garage

I think it's the diff that whines. My '80 930 whines like crazy.
When I'm driving in parking houses, it sounds like a sowing machine.

Thought maybe new tranny oil would help, but no luck.

BlueSkyJaunte · 08-11-2002, 03:46 PM

My whine definitely isn't the diff--it still whines when I'm in neutral.

Rot 911 · 08-11-2002, 03:51 PM

My '86 Carrera makes the same noise from the fan. Really does sound just like a turbine.

Bill Verburg · Bill Verburg's Garage

2 reasons for less fan noise;
1^st the fan is driven at lower speed than on earlier cars, pumping ~100 l/s @6000rpm less than the older cars despite its larger diameter
2^ndthe shape of the blades, as on submarines, was designed to be quiet

singpilot · 08-11-2002, 05:26 PM

My mechs tell me that the chains are what whine. When I had the Carrera tensioner (oil fed tensioners) mod done, and the ramps, guides and chains themselves changed, they said the whine might change a little because of the differences. It did change. They were louder for a couple of days, then went back to the usual.

They did a valve adjust, and a valve timing check and discovered that the rocker shafts on one bank were incorrectly offset. They recentered them in their holders, and couldn't see any damage from that. It was obvious (scars on the head under the chain cover on the same side) that one chain had let go in an earlier life, and the guy that did the repair didn't know his way around a p-car.

Sometimes, not even a pretty complete prebuy inspection catches everything.

Michael Krebs
'80 911SC SCWDP
'83 944

cary · 08-11-2002, 06:07 PM

My 3.2 whines too. Mine is fan belt and pulley related. If I over tighten my belt I can make it go away. But the belt deflection is too tight.
I believe it's because we can't get a 9.5mm wide belt. IMO. Not based on scientific measurement.

pbs911 · pbs911's Garage

There was a thread about this last month. 10% of teh noise is the fan. About 90% is the chains.

Paul Franssen · Paul Franssen's Garage

The "turbine whine" is one of the things I love about my '88 Carrera 3.2. Other than that, I like wine.