whinning 915 transmission, causes ?

Mukilteo911 · 08-26-2002, 11:26 AM

I just upgraded my 1970 911 to a 915 transmission ( early type with mechanical spedo and without helper spring ) from the 901.
The transmission under load whinnes quite a bit in all the gears.
The 901 did only in 4th.

I made sure the pilot bearing was well lubed.
I replaced the oil in the transmission so it is fresh.

It could be that I have not adjusted the clutch correctly. I just tightend the cable so that 1st and reverse did not grind.

The transmission seems to go into gear very well but the noise is crazy, any ideas.

Mukilteo911 · 08-27-2002, 01:57 PM

Does anyone know if this is likely a bearing problem ? or is it a bad gear issue. The whinning is a high frequency which increases in frequency with the RPM under load.

Again, the car did not have this issue before I put the 915 in it, except in 4th. I had just figured that my 4th gear was not as worn as the others and possibly whinned because it did not fit as well.

82SC · 08-27-2002, 01:58 PM

mine did when the tranny oil was low...

even after I filled I get a whine in a certain range of RPM like 4-5000 in 3 and 5th...but actually now it has gone away...strange...

MJ

john walker's workshop · 08-27-2002, 02:29 PM

most likely ring and pinion related. improper clearances, gear face wear due to inproper clearances, or possibly the ball pinion bearing (4 point bearing) has too much end play.

Mukilteo911 · 08-27-2002, 03:05 PM

So what is the best way in determining what the issue is, the bearing or the ring / pinnion ? Should I just figure that I replace these parts and try it out ? apart from the noise it works well.

TimT · 08-27-2002, 05:47 PM

sounds like ring and pinion....

however does your car have a full interior? back seats? carpeting? engine sound pad?

If you have a stock car w/full interior being able to hear the tranny whine while shifting up sounds like a problem.... but if you stripped the interior, you might be hearing the normal sounds of the engine and the tranny for the first time

Mukilteo911 · 08-27-2002, 06:53 PM

thanks, the car has no interior other than seats. But as I said before the 901 did not sound like this.

I will look at what it takes to replace ring and pinnion and get some $$ refunded by my supplyer.

Jdub · 08-27-2002, 07:14 PM

You could probably just drive it down to JohnW - he's over in the Greenwood/Phinney area.

John

Mukilteo911 · 08-28-2002, 10:28 AM

Yeah, he's my mechanic, he works on all the stuff I can not figure out. I like to do what I can because "" sometimes"" it is really fun. But other times!!!!

I'm at the point that I just want to drive my car for about a year and not pull the engine. You have to see the car. it was going to be a cool 70 rs, but some freaked out girl hit the frount and yanked it almost off on sept 12th, she has just been called in for duty and was a mess. Crushed a perfect steel s bumper and ruined my project. I pulled the front out, welded it back on and put a used fender on it and pulled out the hood and put hood pins in it. I just want to paint it and drive it for a year until I can find a new chasis to start with. So if, you know anyone with a long hood chasis in the NW area let me know.