Gearbox woe's on 915
Posted: Sun Jul 23, 2006 3:29 pm
Hi all,
I dont know what to do. I bought the car with 128.000 miles on her and a fantastic gearbox. Clutch was changed at 115.000 miles, the linkage was set up spot on, synchros in very very good condition.
At around 128500 metal fatigue broke the gearstick-end of the gear shift rod. It is the part where the head shift rod is attached to the gear shift rod. I was about to go on a weekend away so I asked my indy whether it could be repaired without ordering any new parts as it was friday evening.
The guy clearly said that it could only be repaired temporarily and that what he was going to do is ill adviced but considering that I wanted to take my car away, it was decided to weld the head shift rod to the gear stick rod.
When putting it all back together, I heard him on several occasions grind the first and reverse gears. The car could be used but when rushing it from 2nd to third the synchro crunched. "Okay", i thought, "lets not rush that one then " and I kept driving it.
Consequently, I bought a second hand gear shift rod and all the couplings. When the engine was rebuild at 132 454 miles I had it all changed over.
Clutch was measured and had 60% left.
First and reverse were difficult to engage but I could engage them if I waited until the car was idling. Again, I was in a hurry so I thought "b*ll*x to that, I 'll bring it in later".
Car had its 1000 mile post-rebuild service and I asked my usual independant to adjust everything and change the gear box oil with swepco. Apperently there is a "lot of play at the back with the U coupling" but I have no idea what he is on about.
The situation now, after a good drive of 1200 miles, is that
1. I cant engage 1st and reverse without switching the engine off
2. when in reverse or first, the car inches forward when i release the brakes
3. 3rd crunches below 5500 rpm. Above that, it appears fine.
I will brace myself for a £2000 gearbox rebuild but can anyone please explain to me
a) is it possible that I have slowly destroyed my synchros by having had the gear shift rod welded?
b) is it likely that during the adjusting of the linkage the synchros on 1st and reverse would go?
c) if I have the gearbox rebuild, but the problem is with the linkage, can I expect the same problem? Are gear linkages part of a gear box rebuild?
d) I presume my clutch is slipping- can this be adjusted so I can at least have the gearbox rebuild during the winter?
I never had a reputation for clutches or gear boxes for any of my cars and I have the habit of keeping my cars for a long time. I never had any of these problems with my 911 2.7 either so I feel a bit desparate.
Thanks in advance for your time.
bert
I dont know what to do. I bought the car with 128.000 miles on her and a fantastic gearbox. Clutch was changed at 115.000 miles, the linkage was set up spot on, synchros in very very good condition.
At around 128500 metal fatigue broke the gearstick-end of the gear shift rod. It is the part where the head shift rod is attached to the gear shift rod. I was about to go on a weekend away so I asked my indy whether it could be repaired without ordering any new parts as it was friday evening.
The guy clearly said that it could only be repaired temporarily and that what he was going to do is ill adviced but considering that I wanted to take my car away, it was decided to weld the head shift rod to the gear stick rod.
When putting it all back together, I heard him on several occasions grind the first and reverse gears. The car could be used but when rushing it from 2nd to third the synchro crunched. "Okay", i thought, "lets not rush that one then " and I kept driving it.
Consequently, I bought a second hand gear shift rod and all the couplings. When the engine was rebuild at 132 454 miles I had it all changed over.
Clutch was measured and had 60% left.
First and reverse were difficult to engage but I could engage them if I waited until the car was idling. Again, I was in a hurry so I thought "b*ll*x to that, I 'll bring it in later".
Car had its 1000 mile post-rebuild service and I asked my usual independant to adjust everything and change the gear box oil with swepco. Apperently there is a "lot of play at the back with the U coupling" but I have no idea what he is on about.
The situation now, after a good drive of 1200 miles, is that
1. I cant engage 1st and reverse without switching the engine off
2. when in reverse or first, the car inches forward when i release the brakes
3. 3rd crunches below 5500 rpm. Above that, it appears fine.
I will brace myself for a £2000 gearbox rebuild but can anyone please explain to me
a) is it possible that I have slowly destroyed my synchros by having had the gear shift rod welded?
b) is it likely that during the adjusting of the linkage the synchros on 1st and reverse would go?
c) if I have the gearbox rebuild, but the problem is with the linkage, can I expect the same problem? Are gear linkages part of a gear box rebuild?
d) I presume my clutch is slipping- can this be adjusted so I can at least have the gearbox rebuild during the winter?
I never had a reputation for clutches or gear boxes for any of my cars and I have the habit of keeping my cars for a long time. I never had any of these problems with my 911 2.7 either so I feel a bit desparate.
Thanks in advance for your time.
bert