924s gearbox whine

mr brightside · Mar 4, 2008

hello, i'm new to the world of porsche's and was wondering if any seasoned pro's could suggest why my gearbox whines a bit on my 1986 924s. it seems to do it loudest if you back off the gas, could it be the allegedly troublesome input bearing? is it worth fixing my box or getting a recon one? would one from a 944 fit? which end is the clutch at and would it be worth doing that at the same time?
Reliable information would be graciously accepted, thankyou.

usermjg · Mar 5, 2008

I remember taking out the back seats and carpet, and at which point the gear box sounded like it was whining really bad, it wasnt any worst than it had been, just that i could hear it. Does it feel like anything is grinning? or missing, ie missing gears, jumping out of gear, loss of power? It could just be poor inslation as the box is at the back it can sound like its failing but it isnt

Marc

geoff Ives · Mar 5, 2008

Personal opinion.

They all do it to a greater or lesser degree. If the noise is really bad, go ahead and investigate if not turn the radio up and enjoy your car.

The Clutch is at the front. If you are taking the gearbox out if could be a good idea to replace the clutch if not my previous advice holds.

If it aint f####d don't fix it.

mr brightside · Mar 5, 2008

the gearshift is stiff but does not grind, nice to hear there might not be a serious problem though. can i get a repair kit for the linkage bushes and how accessible is the linkage? many thanks for the advice!

geoff Ives · Mar 5, 2008

ORIGINAL: mr brightside

the gearshift is stiff but does not grind, nice to hear there might not be a serious problem though. can i get a repair kit for the linkage bushes and how accessible is the linkage? many thanks for the advice!

Try www.porscheshop.co.uk
Geoff

Guest · Mar 7, 2008

You will find many a 944 advertised, on eBay or wherever , with the honest words "transaxle whines a bit".
It is usually put down to wear in the two taper roller bearings that support the pinion shaft.
A few weeks ago I was given a partially stripped 944 box that was about to go in a skip. Box was scrap because several teeth had sheared off the pinion. I wanted it to strip down in order to find out how easy/difficult it was (as I have a 924S with a moderately noisy gearbox).

The fascinating thing to me (sad isn't it?) was the state of the pinion bearings. Many, many small indentations where tiny fragments of metal had been trapped in the bearing races.
This pitting is what produces the noise.
It was pretty obvious that it wasn't just a short term thing i.e. bits from the broken gear.

"What we need is a magnetic drain plug !" said Sherlock.

"Ah but ..." said Watson "there is already a magnet in the gearbox!"

Well, he's right. But the magnet is in the wrong place as far as the diff bearings are concerned. The oil does not circulate in an orderly fashion past the magnet so it only picks up some of the particles that are produced by normal wear and tear.

The probable answer is a proper magnetic drainplug - or even two (one for the filler plug could only but assist in gathering bits).

Does anyone in the States manufacture them by the way? I have contacted a UK firm about making up a batch and am sending them a standard plug with details of internal clearance should the magnet need to project inwards a few millimetres.