Last night I heard a bad noise...

[seedmuse]

In the middle of a busy intersection. I have 20 minutes to get to this job. Clutch in, half way, rev, crunch, uh oh, clutch out, but I'm in 1st gear, oh god, what's that!? Light still red, good. Restart the car maybe that's it. Restart fine, heart pounding starting to sweat, god its hot in here, is the heat up? Light still red, this is a long light, meanwhile it will not go into 1st, sh**. Second yes, third yes same travel as first, not working. Light green! Into second and limp home, goes into third too but I accelerate and get a bad rattling sound. Oh god what have I done, my baby.

Same this morning, I checked. Will not go into first but all the others and reverse. Help me diagnose this please. Obviously the transmission and I've read other posts and still would like to know what I'm talking about when I do talk to someone in my area: East Northport, Long Island, NY. I know I should have seen this coming, the shift into second was always rough, but I learned how to be kind and slow to it. Not 1st gear though. Thanks for any help and advice.

1978 911SC
206K miles

- Matt

[Joe Bob]

Drop the inspection plate on the trans, see if you have any chunks in the fluid. If not, maybe look atthe shift fork....good luck.

[Flat6pac]

Drop the inspection plate on the trans and see if the fork is loose thats attached to the plate. If it is loose, dont try to fix it but new or used get one that is factory tight. This is the fork that directs the disengagement and engagement of the gears.
Bruce

[seedmuse]

Thank you, thank you.

Forgive my ignorance, obviously I need a proper manual, but for a quick answer, will "drop the inpection plate" mean engine removal?

[pete3799]

No you do not have to drop the motor. Just drain the trans. and remove the cover on the passenger side of the tranny. Make sure you can get the fill plug out before you drain the oil.

[Thomas Owen]

Up until you got to the point about hard to shift I was thinking a CV joint. Still might want to check the axles and all CV's.

Good luck -

[Gunter]

206k Miles may mean a rebuild for the 915 transmission especially since shifting into 2nd was always rough.

From the shift-tower mechanism, pedal cluster, cable, C-spring, levers to the clutch itself, there are many bushings and adjustments that wear out.

Get the Bentley SC Repair Manual. It has good descriptions with pictures.

If no work has been done for many years, the whole mechanism from end to end should be checked. It isn't just an easy "turn a little screw" fix.

Components need to be good and adjustments correct. Is it time for a new clutch?

Check/adjust the above first before opening the inspection plate. Make sure that the filler plug can be opened before draining the oil. If your drain plug has the internal hex (17mm Allen), that's a challenge in itself. You'll need a clean, sharp-edged 17mm socket for a 1/2"-drive with a short extension and a breaker bar handle.

Get the Bentley and read up.

[Christien]

Here's a bit more info, in the "for dummies" category, in case you're new to this:

First, you don't have to jack the car up, but it does make it a bit easier.

You want to go in underneath from the driver's side. Find the fill plug - it'll be a 17mm, either "innie" or "outie". If it's an innie, you'll need the correct hex-head socket, and be careful not to round it - you may want to hit the case around it with a blowtorch first. if it's an outie, you're fine, regular 17mm wrench or socket will do the trick. You want to pull that filler plug first because if you drain the tranny then can't get the filler plug out, you've got an empty tranny and you'll have to tow the car to a shop to get the fill plug out so you can refill.

Once you're sure the fill plug can be removed, pull the drain plug on the bottom to drain the oil, but keep an eye on what comes out, even if that means sifting through whatever container you use to catch the oil.

Once that's done, look for a little plate on the bottom of the tranny, about 2" x 3" maybe. It'll have 4 x 11mm (maybe 10mm?) nuts on it. Take that plate off and that's where the shift fork is. See if anything's broken or loose. The shifter fork should move around easily by hand, but nothing should be removable. Do take note of its orientation before you move it too much so you don't accidentally move it somewhere it shouldn't be. Take lots of pics of that and whatever comes out with the oil, or any other loose bits and post them here, we'll help diagnose based on that. When you replace the plate, you'll need to clean both mating surfaces up very thoroughly and use a sealant like loctite or something, or a new gasket (I would advise sealant).

[Gunter]

"First, you don't have to jack the car up, but it does make it a bit easier."

Having done a few of these, I'd love to see someone doing any work like adjusting the clutch, draining the 915 and refilling it, without jacking up the car.

And with a blowtorch yet.

Please! Let's be realistic.

[Christien]

I've done both - adjusted the clutch and drained/replaced tranny fluid with the car on the ground. I agree 100% it's way easier to jack the car and, outside of necessity, can't see why you wouldn't, but I can attest that it can indeed be done! (clutch adjusted in a gravel driveway with just a wrench and vice-grips, and tranny fluid changed on the way to the track in a buddy's garage with no jacks or stands, aside from the toolkit jack, and no way I'm getting under the car with it just being held up by that!)

[seedmuse]

Got the Bently manual and dropped the inspection plate with a friend (finally!) and I guess the pics say it all. A bunch of dog teeth bits and a perfectly fine and solid shift fork. The fluid was weird and milky too. We tried to move the big gear closest to the front but it wouldn't budge. Moving the rear wheel all the others rotated fine, I'm guessing the big one is 1st. It feels like its seized up in there like if i had enough force it would come loose.

I'm not going to push it, at least I want to be able to drive it to the shop where I get the 915 rebuild.

And so I'm in East Northport on Long Island, close to Huntington with lots of options there and I'm looking for advice on a guy to use and a ballpark estimate on the cost.

Thanks for all the help.

[kodioneill]

That's to bad. I think you my want to consider using a flatbed to get her where you have to. You may cause more damage to the transmission if you drive it. Or pull the engine and trans yourself ( it not that difficult )then take it to be rebuilt.

[Superman]

Hold an Engine Drop Party at your place. Fire up the barbecue, fill a cooler with beer and tell people the Hooters girls will be there.

[Christien]

Yep, I agree. Pull it yourself, have some friends/other Pelican folks over, get a case of beer and remove it yourself - that's half the labour (well, not quite, but still). Take the tranny into the shop, or better yet, rebuild it yourself. Trust me, it's completely do-able - if I can do it, anyone can, with the right tools and the right instructions. Rebuild cost would probably be $1000-$1500 for parts and labour. Or buy a rebuilt 915 for $2500 or so.

[Gunter]

Taking the engine/transmission out yourself makes it possible for you to replace some of the parts and seals on top of the engine. (Breather cap gasket, oil warning switch, thermostate seal) And whatever needs attention.

Even though someone will claim that it can be done, don't try to remove the unit without lifting the car.

[seedmuse]

Christien, do you have a link to the "directions" you used? And ballpark what do the tools cost, this may totally blow the do it yourself budget.

[Gunter]

"Search" on top of the page is your friend.

Lots of info on 915-repairs with pictures etc. and yes, it takes some special tools.

Parts for the 915 are the major cost, not the labor. More like ~$2000.- Plus for a quality rebuild.

[GaryR]

Plan on $3000 for a full rebuild unless you DIY and you won't be unpleasantly surprised. Gary Fairbanks (Stamford, CT area) is the common choice if you can get the tranny to him.

[gsmith660]

Yep pull it and take the tranny to him you drive it with that much metal in there and you will do alot of damage. Besides you will save alot of money doing the drop yourself.

[E Sully]

Porsche Wiki: How-To: Porsche 915 Transmission Repair Tutorial Part I