Sending out S.O.S someone please help
 

Hey guys as some of you may know I picked up my 79 930 on friday and drove it last night and it drove great. I was driving it on the way to get it dynoed when I was at a light and revved it to 3rd gear and dropped the clutch and I felt a snap underneath the shifter and it revved all the way up like it was in neutral, well it was in neutral. Now its stuck in neutral and wont go into gears. I dont think the tranny went out on me as I can still shift into gears. What could have snapped? Im thinking the shifter linkage but I dont know much about porsches. Any help will be greatly appreciated. Thanks!

btw I am in Charlotte, NC. If any guys out there can help me get this fixed (being it doesnt need a tranny reuild) I wouldnt mind paying good :)

Coulda blown the clutch, wait for others to chime in.

Congrats on your new Porsche - sorry about your mishap. Porsches BTW don't generally like line launches. Or so you now know.

Could you better explain:

well tranny was rebuilt 2 years ago. This is the 915 5 tranny and new HP(?) clutch. When I push the clutch down it feels strong. If I push the shfiter into 1-5 gear it stays in neutral.

If you get it up on a lift.....you can try to hand shift it.....you might want to post where you are located.

Take off the cover on the hump behind the seats and check the shift coupler; its clamping collar may have loosened or the plastic bushings within the coupler may have failed. If not that, then the collar or joint on the shift rod under the shifter may have failed or loosened. I don't believe the 5-speed 915 was original with a 930 engine so it will not do as well under the higher horsepower loading. Dropping the clutch will cause rebuild time to come sooner; 915 parts are expensive - just the basic items for a rebuild end up around $800 to $1200. If you want the "drag"/stop light type performance you may want to consider a different car unless you have a thick wallet.

Easy things to check are having someone in the car and shifting while you observe the linkage. If it's moving at the trans, then some shift forks are bent or broken' or there is some other internal damage.

I think the 930 came w/ a 4 speed and it was much different. There are High end trans available that are 5 speeds by RUF, (I think) and others that are designed for the power. WEVO makes a bunch of trans parts too.

Could be as easy as a loose CV joint?

Doubtful, for that to be the case, he would have had to A- shear the CV completley in two, AND B- have an open diff.

I suspect issues in the trans.

Did he say he was stopped nd selected 3rd gear, and dropped the clutch?

Ouch.

sorry I meant to say 1st gear.

OK, we have a 915 5-speed with a 930 engine. Do we know if the 915 has a LSD or open differential?

I would first proceed with inspecting the Constant Velocity (CV) joints. A CV coming loose at the transmission with an open differential has exactly those symptoms. If it was an SC and has the 100 mm 923 CV joints, they are way too small for a 930.

When inspecting the CV joints, feel the rubber boots. It is possible for the cage to come apart and under load the races spit the balls out into the boot.

I agree inspecting the linkage but only because it is easy. From the description that doesn’t sound like the problem.

Next I would remove the shift pivot plate (after first removing the drain and fill plugs) and inspect for anything wrong. You will need a new gasket here.

If all of the above confirms everything appears OK, time to pull the engine and transmission for better inspection. It could be the clutch or internal transmission.

Best wishes.
Grady

Grady, I would think a CV joint in that condition would make a bit of a racket when the car was in gear and the clutch released.

Thinking further, as this car has a non stock trans, I guess it's not a far reach to think that it could be missing a ltd slip....

Lets hope it's a CV.....

Bogeydrvr just had a similar problem, thought at first it was his clutch. Giveaway was that when he put the car in gear and let the clutch out the speedo would begin to climb. Try that with yours... if the speedo is registering yet you are not moving look for sheared bolts or broken cv joints. This is the thread:
Broken CV Joint
When you first posted that you dropped the clutch in 3rd gear I kind of wondered what DIDN'T break!

yes! the speedo is going up. The axle and cv joints look fine to me. What exatly do I need to inspect?

I had a similar circumstance happen to me and it was the shift coupler bushing under the small panel behind the seats. It really gave no notice of breaking and would just shift in a couple gears. The linkage may also have came loose. Like Grady states its real easy to check too.

ok well spoke to my father whos in the parts business. He told me to jack the car up and put it in first gear, then see if I can push the tires, the left tire moves freely with sounds of metal scraping coming from cv joint area, and right tire moves but you have to force it. He also said to spin the tires and see if the belts were moving, they did not. Now Im left to figure out what to do.

anyone know of a good shop in nc?

ok well put the car in 5th gear and put the e brake on, looked under neath the right cv axle (going into the tranny) was spinning, the left one was not.

Broken CV joint it is, then (unless there's something catastrophically wrong with the internals of your differential). Check this thread out, it has some good pictures of a driveshaft change:
CV joint Replacement
Post later to let us know what exactly it was and how it turned out. And take it easy on the clutch!

thanks, anyone know where to get cv axles? I doubt pepboys or autozone carries them.

Get your CV joint/axle assemblies right here at Pelican Parts. :D

problem is, its a 1979 911sc body with a 3.3 930 engine. Im not sure what cv axle I need.:confused: Any way to find out?

It's the body and trans that dictates which CV to use....

Is the car an original ’79 930 with a 915 5-speed replacing the 930 4-speed or is it a ’79 911SC retaining the 915 transmission with a 930 engine? There is a very significant difference in axle assemblies. The first three numbers in the 1979 VIN are 911 for an SC and 930 for a Turbo. With the ’80 models the numbering system changed.

Best,
Grady

79 sc with 915 tranny and 930 upgrade engine in it. I will order cv axles for the 79sc.

Good, we resolved that potential ordering problem.

Another issue is the size of your CV joints. What size Allen wrench fits the CV bolts? It will be either 6 mm or 8 mm. How many bolts through each CV joint? It will be either 4 or 6. Does the outboard CV joint have bolts?

How many miles on the car? If many, you might consider replacing both axle assemblies. With a 930 engine (pretty spectacular upgrade) they see far more torque. That is why 930s have the big CV joints and that huge 930 transmission. If you have 100 mm CV joints, you should seriously consider upgrading to the big 108 mm 928 axles used from about ’84 on. They are the same size as the Turbo CV joints.

Regardless, you should order a full set on new CV bolts. That includes new OEM Schnorr Safety lock washers. The proper term for the CV bolts is “Socket head cap screws.” Your CVs take a gasket between the flange and CV joint. Do the replacement axle assemblies use the gasket or do they have end caps?

While the axles are out, confirm that all the plate washers are under the bolts.

If the new axles have end caps, make sure they seat properly to the flanges at the transmission and stub axle with no interference.

When assembling the axles pay particular attention to the length of the bolts. They should penetrate the flange 1-2 threads with 1 ½ as ideal. There are varying thickness of CV joints and of the metal retainer for the rubber boot. Additionally the end cap adds a little thickness.

This is about a 2-hour thread but very worthwhile on this subject.
Pelican rcecale, Randy’s classic thread.
”Reconstructing Constant Velocity (CV) Joints”
It might be valuable to print a copy and highlight the important sections for yourself and/or mechanic.

A critical issue is to torque the CV bolts again after about 100 mi of use and at each major service – at least annually.

Best,
Grady

thanks alot! I checked pelicans new parts and they have Complete Axle w/two CV Joints & Boots 911 Turbo (1985-89), would that fit? Thanks

Probably not; it is more likely the 100mm standard axle is still installed which could be why it failed. If the car's wheel hub and transmission is still set up for the 100 mm axle you just can't swap in the turbo axles as the bolt pattern and bolt size will not match. I will conjecture you need the 100 mm axle assemblies (923-332-033-02-M60) at $257.52 per assembly and 24 8 mm x 50 mm long bolts per axle assembly (900-067-211-09-M100) plus the joint to flange gaskets (4) and 24 8 mm (S8) Schnorr washers.

However you need to check which axles are installed per Grady"s instructions as the car is not stock and there may have been changes in the axles.

I checked and its 6mm. Am i safe to assume to get the non-trubo cv axles?

got it fixed over at the 911 shop in charlotte, nc. I broke 5 out of 6 studs going into the axle. Well I feel alot better now.

Yep, Terry is very good. Let him spend a few hours with the car and he will tell you everthing you need to know about its condition.