re: engine noise

[Nick]

Hi,

The other night i took my (1996) 993 carrera for a run, about 20-25 miles, got off the motorway and shortly after got a intermitent squealing noise from what sounded like the engine complartment, the noise appeared to clear itself at lower speeds ie. 45-50mph, on the drive home - approx same mileage, there was no squeal sound, but engine sound(tone) appeared a little louder, appears to be running ok as when i was on the motorway/sliproad i revved quite a bit, ie. up to 65-70mph in second with no odd noises !.

I checked the belts and all appear ok.

I also checked the oil, engine was hot and running, on level ground, the level indicated just below the max mark on the stick, thus not running on to little oil ?.
Just wondering What would a reading be on the stick if the thermostat did'nt open???, thus me thinking level was correct with engine being hot, the level on the guage (instruments) at hot shows the position of between 4 & 5o'clock at idle.

Would this by anything to be to concerned about.

Thanks in advance.

Nick.

 

[Guest]

Hi Nick, happy to look at it for you if you want. I've got the tools if it's slipping belt(s).

Cheers,
Rod

 

[Porker993]

If it is squealing belts, then a quick blast of WD40 stops the noise for a while. The only permanent fix is new belts.

 

[MarkG]

ORIGINAL: Porker993

If it is squealing belts, then a quick blast of WD40 stops the noise for a while. The only permanent fix is new belts.

A little french chalk dust (puncture repair stuff) works the same as WD40 but lasts longer.

 

[Guest]

What if its not the belts? Do our cars have a thrust release bearing? The reason I ask is that in the past (pre-porsche) I have experienced a screeching sound and it turned out to be the old thrust release bearing. (where the bearings had basically dried out of grease or completely worn out)
These were of course changed when you changed the clutch, of which I have had the experience of in my youth, more than once, as I couldn't afford a garage to do it, so I did it myself with the help of the good old Haynes manual. I have not however had the 'opportunity' to change a clutch in any of the 911's I have owned. (perhaps this is a good thing) anyway just wondered really.

Glenn

 

[Guest]

ORIGINAL: valvebouncer
What if its not the belts? Do our cars have a thrust release bearing?

Yes, they do. There is also the bearing for the alternator pulley (which runs inside/behind the fan), which can seize and make the pulley slip a bit on acceleration. This can be detected when you remove the V-belt to inspect it/the pulley/bearings.

Roddy