Technical Blog:

Gearshifts.  Do bumps or rough pavement cause the gearshift lever to rattle, jump out of gear?  Is yours stock, an after-market short shifter?  What is the hot setup/ tune-up?  Thanks to Carter Willey for suggesting this question. 

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From: John Allen;  Recently purchased a 1968 5 speed, with 1st gear at bottom left, located through a gate. I understand that this "racing" pattern was later changed by putting 1st in upper left. Anyway, I find first gear somewhat difficult to find at times, especially after coming to a stop at at light (as opposed to when just firing up the engine). Shifter just does not want to allow it in into gear.  Must be very careful and often must repeat the attempt a few times.   After driving a 356 for years, I find this very annoying. Is this a normal occurence?  What repair/maintenance is suggested?
Thanks for any help.
John Allen

From: Patrick Van Asbroeck; ; Dear Rick, The gearbox is the reason why my 912 '68 has been taken apart. Problem was when releasing the gas pedal while still in gear I could clearly here a grinding (metal on metal) noise coming out from down under. This only after 10km driven when the oil got warm. Otherwise the box worked just fine.  One mechanic said not to worry while another one said it better be checked out. Don't like driving around in a car that sounds like your breaking something. So I took the box apart myself. Before I did that I changed the gearbox oil just to make sure it wasn't the oil. It wasn't. I noticed though that in the old oil there were some small yellow copper pieces. That proved something was wrong. I opened the gearbox after reading a couple of manuals! Better be prepared a bit. What did I find?
1. the toothwheel which drives the speedometer is supported in a steel bushing. Probably they were not very well aligned as it was clear to see that the copper pieces came from this. Not a real problem.
2. All the rest looked oright although in one magazine article (Oldtimer Markt Sonderhelft 22) I read that the contact pattern between the ring and pinion wheel should have a rounded off rectangular shape. It didn't have this shape. The ring gear teeth were touching the pinion wheel teeths over the full surface! I didn't know what to think about that. Apparently there are two geartypes used in differentials: oerlikon/klingelnberg and gleason. Anybody has an idea whats was used in our Porsches and what contact pattern we can expect typically? Anyone had the same grind before?  What did you find out?
Anyway I finished the job there and handed the box over to a gearbox specialist. Result: he didn't  find any damage either. Everything in perfect shape. Only problem found was too much clearence in the differential carrier. That will be adjusted and new seals fitted. Total cost around 250 dollars.
When splitting the gearbox from the engine I found a 2.5mm thick plain washer pressed between them!! Someone had been there before. Its possible this was another reason for the grind.
Otherwise the gear linkage is all standard but I found all plastic bushings and dust boots in need of renewing. Also the three plastic guides for the gas pedal linkage in the tunnel between the seats will be replaced. I found two broken and one missing.
Thats it for now. Can't wait to get back on the road again!
Patrick

From: Typ902;   I have the stock shifter setup on my 912/5 and have never experienced road bumps causing rattles or coming out of gear.   My car has the early engine mount system which does not have all of the rubber bushings that the latter mount has.  I do know that there is a lot more engine/transmission movement possible with the later engine mount system.  Worn rubber mount bushings, combined with worn nylon shifter bushings, might be the cause of the problem described.  One thing that I did to improve shifter feel was to replace the nylon shifter bushings and this makes a big difference in an old car.  With everything in good shape the 902 transmission is a real pleasure to shift.  I would never install an after-market short shift kit, how could this be better than what the Porsche engineers designed?

From: Marc Finley;  ; 912E 1976  915 transmission, 118,000 miles, Very pleased with transmission, has a short shifter - wouldn't drive it without one recently replaced the two nylon guides in the shift linkage best $10 I ever spent. Marc Finley, Dallas TX

From: jack frost;   Yes my 912 has came out of gear when going over bumps.  I partially cured the problem by replacing all of the bushings in both the front and rear.  I used to own a 1962 Karmen Gia (1n 1967) that did the same thing.  It is partially due to body flexing.
The complete cure is to install a full roll cage.  The chassis is then stiff enough that nothing bothers the shifter.

From: Pat McCartney;   Hi, I have a stock shifter in my '69 coupe, I just replaced all the bushings in the shift linkage, I got rid of alot of the slop but I still have a very large shift pattern, will a short shift kit solve this problem ,or is the kit just hype. Has anyone modified the stock stick themselves with any luck, what are the problems?
I have access to the machine tooling to do the job , but am reluctant to try, not knowing the problems that might crop up.
Thanks,      

From: Bill Todd;   Hey Rick!
I used a short shifter and epoxied it all together per the instructions. It has worked well over the long haul, and I'm quite happy with it.

One item you mentioned was "jumping out of gear." I don't know if you're aware of it or not but when you pull the engine in a 912, (depending on the year) just about all that's holding the tranny in is the linkage between the shifter and the Xaxle. If you have the car jacked up, it will tend to bend the linkage. This seems to "pre-load" the linkage and makes it act bizarre, depending on the way it's bent.

This may have been done to the car previous to your owning it, and you can't control that. The linkage is bent, and it will be very sensitive to any movement of the engine and Xaxle mounts. If you are pulling an engine, use a jack under the Xaxle, support it and don't let the vehicle sit, suspended in mid-air on
jackstands. Your shifter may be okay, your linkage may just be bent.

Second:
My 912 has a 5 speed. It has the spring loaded gate that prevents accidental shifts into reverse. My ball socket, etc  was lubed when I installed the short shift. Evidentally, putting the additional strain (?) on the gate was too much for it. I was down between Hearst Castle and Carmel and I all of a sudden
started losing control of the shifting into reverse and low gears. The gate pins had weakened, and the ball socket allowed the gearshift to "slop" all around, with no definite shift pattern. I had to cautiously feel for each gear.

I took it apart in a parking lot at a local market, and wired out the shift gate, allowing positive shifts into 2nd and above gears. Willing hands help me push it out of the parking stall, and I limped home. Upon disassembly, the locator pins had been dry for some time and were paper thin and broke. I installed new gate and springs and pins, and used a "moly-lube" type grease when assembling. I pull the rubber cover back occasionally, and hold down a bit on the shortshifter. I then take a clean tongue depressor or ice cream bar stick and force some more lube down in the ball socket area.
Regards,
Bill

PS. New "top overhaul" went well. No leaks and it runs super!! Probably strongest it's ever run.  I do need to really dial in the right Weber, but I can do that! I have about 200 miles on non-detergent 30 weight oil, and will go back to Kendall 20W-50 and a new spin-on oil filter in about 300 more miles.

See 'ya!
BT

From: Gavin;   Oh yes sir! Jumps out like its sitting on hot coals! Started off just being 3rd (of 5) and now I have had the suspension re-aligned and set to correct (ish) height the rest of the buggers have joined in I think they must have a Jump Rope in there! I intend to check the linkages for wear. watch this space
Gavin
1968 912 (ex-california now London)

From: BUTZIP;   Ah yes the shift linkage.  There is only one way to do this correctly.  A few bucks, a little time and you can have your 912 shifting like new. 

Symptoms:
1)Excessively vague shift gate (lets face it there all vague even when new)
2)Banging in you chassis tunnel
3)Throw of more than a foot or so
4)Nicking reverse (5spd)
5)Can't find gears
6)Pops out of gear

Solutions:
1)Replace the ball cup bushing $5
2)Replace the slide shaft bushing $3
3)Replace the coupler bushing approx $10 (make sure you mark the spline
location on the coupler for reassembly orientation, it will most likely not
go back together in the same location but it's a good reference point).

5 speed mechanism:
While the shift mechanism is out, flip it over on your bench.  You'll see a separate lockout plate.  You will most likely notice that over the years the lever has substantially worn the point of contact between the lever and the lockout plate.   This is often over looked because it's not as obvious as the bushings. 

Solution:
1) Remove the C-clips that secure the two rods (thru the springs) Be very careful those spring pack a punch WEAR SAFETY GLASSES POINT AWAY FROM YOUR FACE USE VISE-GRIPS do this procedure away from anything you don't want a big scratch in like your car!!!!
2) Remove springs and rods
3) Manipulate lockout plate so it comes out (this takes a little bit of twist and pull but you'll get it)
4) oh yeah have a good used one ready so you can put it back together (I'm not sure if these are available new)
5) Assemble reverse from disassemble
6) Watch those springs again they're alot easier to get out than back in. DO NOT try to compress them, simply slide the rod in half way (leave the c-clip on one end), place the spring over one end and with a pair of pliers or vise grips kind of slide it over to line up with the other hole keeping steady
pressure on the rod to feed it through.

As far as short shift kits go, the Weltmeister kit is the best quality that I have seen.   I have the cheap one that consists only of the lever end and an aluminim spacer, crude but effective if the bucks permit, go with the Weltmeister.
 
That's all there is to it, it's the little things that make a huge difference.  This makes the car so enjoyable to drive and precise the way it was meant to be.

Peter Baldauf Learning 912s the hard way

From: Jon B. Kanas;   Hello, I have a 1969 with a 5-speed; stock linkage, transmission and shifter.  My shifter does move when driving on rough pavement, but does not jump out of gear.  It is my understanding that jumping out of gear is indicative of transmission wear, that rebuild time is near.   I do know that my transmission nose mounts are soft, and should be replaced therefore I am uncertain how much shifter movement should be considered "normal", and how much is accentuated by the weak mounts.

My 912 has just over 200K miles on it, and while the syncronizers are weak and will not tolerate agressive driving, the transmission is otherwise flawless.  It has not been disassembled or rebuilt.
Jon Kanas

From: Larry;  Yes I have a stock shifter & bumps do cause it to sometimes jump out of gear & also rattle( 68 912 ) it dosent bother me to much ....................... Larry

From; markmaui;   Hi!!
Mark here, just to let you know that I suffered the typical 912 shifter woes [sloppy, rubber-band feel, bounced out of gear on bumps] when i first got my '68 in 1995.   With the help [kokua] of my Volks-Porsche friend [914 owner], I installed a Weltmeister brand short shift kit.  Installation took two of us about 4-6 hours.
this is a great product, maybe one of the best Weltmeister makes.  The shifts are precise, the throws from gear to gear are much shorter, and the car is much more enjoyable to drive. The downside is that first gear is still a little too hard to find sometimes at stoplights... this always seems to happen during "rush-hour"  [For Maui traffic, anyway]  To be honest, I haven't tried to remove that cover and fool around with the likage adjustment - - i may have somebody with more mechanical skill drive it and try to adjust it. For those of you who are not "purists" in pursuit of an "historically" accurate driving experience,  this is a nice little upgrade.   It is the single best improvement I've made to my car.
This is a great Website.  Keep up the good work.

From: Bruce L. HERRINGTON;   My '68 shifter used to flop around a lot when I drove on rough roads and would always pop out of gear every time I went across a deep gutter leaving work.

I replaced the trans mounts (don't recall if they were 912 or 911 parts) and it made no difference.

I replaced the nylon cup and bushing at the front of the shift rod, just under the shifter mount, and that cured it for some 40,000 miles.  Now the problem is coming back, but I have not yet pulled the shifter to make sure that the front bushing is shot, but I'll bet it is.

That's my $.02 worth, as they say.

From: Greg Bryan;   My 912 used to jump out of gear going over railroad tracks, etc.  Some 912s have an elaborate rubber mount both front and back - maybe 68 on, but I'm not sure. I think it was an attempt to isolate the shaky old 4 cylinder from the occupants.  At any rate, with age it becomes way too flexible and allows the engine and trans to move around too much.   The easiest cure is to put a 911 style mount on the transmission - it's much firmer.  There's always a tradeoff - you'll feel the motor vibrations more.  You can also install the early style 912 rear mount.  It's also a lot firmer.  I personally like the overall firmer feel of the car with both mounts installed. These are all bolt on operations - very easy.  You have to install shorter studs on the transmission for the 911 mount if my memory serves me ...

From: Robert Burn;   My transmission and shifter are totally stock and have never had anything done to them; it has never jumped out of gear!

From: Gregg Dunphy;   The gearshift and related mechanisms as well as the tranny on my 912E are all bone stock. They work flawlessly: shifting is tight and precise without requiring excessive effort; the trans has never jumped out of a gear under any circumstances. I really didn't expect the performance to be otherwise since the car has only 260,000 original low miles on it. ;) Gregg

From: John F Lacey;   Rick: When I had my rebuild done some four years ago, the guy mentioned that he had spot welded some piece (I still have no slight clue exactly what -- maybe a washer or bushing in the shifter tower assembly -- his German accent was oppressive and I just wanted to drive the car home) to reduce "play," and it has been smooth ever since. No shake, no rattle, no roll, no popping out of gear. I have been tempted to raise the fulcrum with a short shifter kit, as it is fast, cheap and easily reversible, but in deference to originality I have not done so. The only shifter issue I have had is a problem with a loose knob. The corrugated ferrule just hasn't ever kept it tight. I bought a new one, and the knob is new/crack-free as well. I have tried lots of Rube Goldberg measures, including Teflon plumbers tape and epoxy, each to no avail. Member suggestions welcome. Very best regards, John L.

From: Jim Hager;   No problem with the gearshift.   It's stock on our 1968 coupe. Jim Hager

From: Suyenaga;  ; My 912e's shifter pops out of gear all the time, especially in 2nd gear.  Also, I am having problems shifting in 5th gear smoothly now.   Anyone else have the same problem?

From: Randy Cohen;   Shifts great! A 69 with the weltmeister short shifter and all new bushings.  No glue together stuff for me. Randy Cohen 69 targa

From: Nichols, Eric;   Regarding the transmission popping-out:  Assuming the transmission is in good shape, I have found the main culprit to be the  front transmission mount.  The 912 uses a mount with two large rubber blocks for vibration isolation.  The blocks flex enough to allow the transmission to bounce during sharp bumps, resulting in occasional popping out of gear.   This symptom gets worse if you have upgraded to stiffer shocks, swaybars, and/or torsion bars.  New rubber blocks may help, but may not cure the problem.

The best fix is to swap for an early 911 transmission mount, which is lighter and has much less flex.  It has the added benefit of providing more clearance for a rear sway bar.
Eric Nichols
1967 912

From: Jason Terada;   I'm running the stock shifter, which isn't too bad for a remote setup--its better than my old Alfetta GT. It does rattle on occasion, but has not jumped out of gear. Shifting into first can be a little vague at times. My only change to it was when I replaced the aftermarket walnut Porsche crest shift knob with a stock black plastic one.

A habit I picked up years ago from driving Alfas, which are known for their weak synchros, is moving the lever into second gear before shifting to first, while the clutch is engaged. I have also found this useful in the Porsche.

From: Don Melcher;   Our 69 912 has an aftermarket shift kit - short shifter? After we purchased the car a couple of months ago, I took it to the mechanic for new shocks, and he drove me back to the office and commented on how "tight" it was. The pattern is very positive, and it does seem easier to find the gears compared to my brothers 69 911 that I drove 30 years ago, although that was a while, I  don't think my memory was that bad.

I remember when I test drove this car it seemed a lot easier to drive than I had remembered. I only drove one other 911, a later 70's or maybe even 80's once, so I don't remember that one. All the others have been speedsters or 356's, so I don't have a lot to go by.... but I really like the way it shifts. We got luck and found this one as the first car we looked at - rust free and in reall nice shape.

It does pop out of second when I hit a bump just before turning on my street on the way home, with my foot off the gas.... I remember my old 66 VW bus doing the same thing there. It also has a sluggish syncro in second, but I don't think that has any relationship. I figgure we'll drive it for a year or two, and once the major problems and bugs (read expensive) are worked out - so far shocks, ball joints, front (gen. pulley end) oil seal have been done - we'll think about the tranny. Still have a clunk in the front end on slow bumps, but 99% better after ball joints.
Don Melcher & Saralynn Nusbaum
69 912 Targa - we love it!!!!!!!!!!!!!

From: Chris Smith;  Hi Rick, My 912E has the stock shifter but the bushings have been replaced. My shifting is solid but stiff. I was going to go with a short shift kit but my shifting is already stiff and I thought that a short shift kit might put too much leverage on the forks and other internals. I talked to the guys at Parts Heaven, our Northern Calif. Porsche dismantler, and sure enough they have seen damage from some of these short shift kits. I don't want to drop names but the most popular SSK from many parts dealers is one that reportedly causes problems. I hear that Porsches SSK is a better product but I still worry about putting too much pressure on the forks. I'm hearing lots of nightmares about linkage and/or coupler adjustments too. I can't wait to hear from others about their pros/cons related to the SSK. Keep up the great work Rick.
-Chris

From: Neil M. Fennessey;   Rick: This suggestion came to me some years ago from Eric Nichols, who also drives a '67 912.  The "hot" set-up is to trade in the 912 front transmission mount for an early 911 transmission mount.  It's a more compact, less sophisticated unit.  The gear shift will no longer pop out of gear in the bumps, however, there will be an increase in noise/vibration in the cabin.  It's also possible that the altered system's vibration characteristic might lead to a more/less (unknown) premature failure of the
oil cooler mounting flange on the engine block. 
Your mileage may vary.
Hi Carter!
- Neil
'67 912 (Ol' Blue)

From: Jerry;   Carter Willey had an interesting question. My 1967 Targa has the 5 speed (stock set up), and I've had none of the problems he mentioned. My only problem is that I still find the gearshift pattern to be vague at best, especially when a quick shift is needed. Thanks,  Jerry

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