915 transmission problems

dan911 · 08-01-2003, 06:25 AM

Hi,

I've got a 1985 911 carrera 3.2 and I rebuilt the transmission about 5000kms ago. However, I still have difficulty shifting up from 1st to 2nd gear and down from 5th to 4th and 3rd to 2nd. It just feels sticky. I've got to try forcing it 2-3 times before it slots in. Anyone having the same problem out there ?? Is this a 915 quirk??

Dan

yelcab1 · 08-01-2003, 06:38 AM

Similar problems before. Try:
adjusting the clutch, adjusting the shift coupling, inspecting the clutch (hard), changing the fluid.

Then, if that does not work, you live with it or rebuild it again.

targa911man · targa911man's Garage

If there's no grinding, it sounds like the coupling is a little out of adjustment. The 1st to 2nd stickiness is normal. If you can get some Swepco 201 fluid in Singapore, put that in too.

RC76 · 08-01-2003, 07:36 AM

It's amazing what a gear oil change will do. Just had mine replaced day before yesterday, shifts a lot smoother now.

dan911 · 08-01-2003, 10:54 PM

Thanks, I'll try adjusting the clutch and shift coupling. Hope that helps cos' it's a pain on the track. Don't think I can get Swepco 201 here though.

Dan

Dan Owens · 08-02-2003, 05:31 AM

Dan,

Sounds like you need to adjust the shift coupler (1st choice)and possibly the the plastic bushings in the gear shift shaft (2nd choice). You may also need to adjust the clutch again (3rd Choice). Swepco is available World Wide (a must), just go to their website and look it up. If you can't find it over there I'm sure one of us could help you out and ship you some.

Trust Me · Trust Me's Garage

You know what's funny. My tranny acts up after it has warmed up? Cold, the car shifts great. After a while, 1st and second become a pain in my rear. New oil?

ruf-porsche · ruf-porsche's Garage

Swepco 201

Trust Me · Trust Me's Garage

Well I guess I got my answer. Thank you ruf. New fluid it will be.

Geary · 08-02-2003, 10:04 AM

Quote:

Originally posted by Trust Me
You know what's funny. My tranny acts up after it has warmed up? Cold, the car shifts great. After a while, 1st and second become a pain in my rear. New oil?

Sounds like there's synthetic oil in your tranny. Works better than Swepco when cold, worse when hot.

dan911 · 08-02-2003, 11:22 PM

Hmm, gotta get me some of that swepco 201!!

Dan

rickpurple123 · 09-07-2003, 06:54 PM

Hello Everyone,
I just purchased a 1985 Carrera 3.2L with 88,000 miles.

I have some 915 questions. The previous owner told me it has always been "sticky" going from 1st to second. It seems that 4 out of 10 times second just doesn't want to be engaged. No grinding, it just feels like it is pushing back on me. A slight force or nudge on the second time, sometimes double clutching, will get it to engage.

I might be able to live with it but the other problem annoys me more. 1st gear grinds if the car is rolling >5 mph and rpm's over 750. Another Porsche I test drove had this same problem. Is this common? I had a mechanic test drive it and he immediately thought 1st and 2nd gear synchros. I have Swepco oil on its way.

Here are my questions:
Is my first gear problem definitely synchro and the second gear problem more just a quirky typical 915 problem? Is it time to rebuild? On the PCa website a tech guy says he had an SC that was sticky going in to second for 20 years. Could my first gear problem ever be solved by adjusting linkages and replacing bushings etc?

Any feedback from this educated forum would be great.

Additional info. My clutch pedal engages about 3" from the floor and I cannot put my foot in front of it and pull it towards me as there is no free play. I read somewhere that there should be some freeplay here.

GB83SC · 09-07-2003, 07:07 PM

Common issues-- 1st to second hard (specially if you shift at less than 3K rpm.)
1st gear( try putting it into gear just short of a complete stop).

bigchillcar · bigchillcar's Garage

rick,
many, many of the grinding issues and trouble shifting into gears has to do with the clutch pedal freeplay. it's a simple system on the earlier cars, not as sure on your model, but mine has a cable adjustment nut back at the transmission, allowing you to loosen or tighten this freeplay. small movements make big changes, try one direction a couple of turns and drive it. if it's better try a little more, if worse, go the other direction. cost? $0

checking the condition of shift coupler bushings, shifter and shift rod bushings would also be advised. these are frequently worn, allowing the shifter itself to slip out of position and makes for missed shifts, etc. cost to check? $0

cost to pull tranny, replace synchros (your mechanics first instinct, unbelieavbly)? pricey
ryan

Sonic dB · Sonic dB's Garage

Rick...do a search on the forum for info on adjusments to make to help your 915 shifting: shifter bushings, coupler, clutch cable & adjust, new tranny mounts, Swepco etc.

These things can help.

Another thing...is just getting to "know" your 915. The oddness of it will seem alarming at first, but generally are just par for the course.

Mine is exactly like yours that you described, and only has 67,000 miles on it.

Ive learned to work with the 915 and made adjustments to my shifting as well as the adjustments to the car itself. These things help, but with every shift I am one shift closer to rebuilding. Im hoping to get at least 100K out of it before I do.

knock on wood

jazzbass · 09-08-2003, 04:24 AM

I find double clutching the 1-2 shift takes most of the notchiness out, at least for my 915. YMMV. Yeah, I run Swepco and have new bushings, too.

Early_S_Man · 09-08-2003, 10:21 AM

Dan,

With your car's mileage, you need to do all of the usual ... clutch adjustment, new ball-cup bushing, shift-rod bushing (both well lubricated with moly grease) and shift-coupler bushings (installed dry) ...

Swepco gear oil is great, but not worth waiting for when other solutions can help or fix the 'hesitant' 1-2 shift ... which sounds like a 'classic' case of gear oil contamination causing the Porsche-dewsign synchronizer to be balky. Change the gear oil with a name brand SAE 75W-90 oil such as Castrol or Valvoline and drive the car gently for 1-2 weeks, then change to SAE 85W-140 gear oil of the same brand and add a 2-3 oz. tube of molybdenum disulfide EP (extreme pressure) additive for heavy-duty truck gear oil applications. If that doesn't remedy the balky 1-2 shift, then you are rushing the shift, and you need to slow down a bit.

Rick,

No, the 1-2 'graunchy' shifting is NOT always indicative of a needed rebuild!

Jdub · 09-08-2003, 11:18 AM

Is there any possibility you did not purchase OEM Goetze synchros/rings etc.?

John

dan911 · 09-10-2003, 06:10 AM

Hi,

a quick update:

Changed my shift coupler, had it and the clutch adjusted and put in new tranny oil. Already put in a porsche short shifter and changed the shift rod/shifter bushings last year. Hmm, slight improvement, but the on-and-off sticky 1st to 2nd, 3rd to 2nd and 5th to 4th still persists. Might have to change the shift sleeves/guides when and if I can afford it!!

Dan