996 Transmission Rebuild and Pinion Bearing Replacement DIY
01-15-2017, 08:34 PM
#32
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The bearings are indeed a bit of a issue with these, especially as they are sealed units. They tend to fret out inside the races which makes them howl when they are failing. Great write up here. I would caution a few things. Having rebuilt a number of these with a wide variety of companies, I have seen any number of people try to do this build themselves to find that they are WAY over their heads. A 20 or 30 ton press may not be enough to press the gears off the shaft. I know that we have broken more than one of these in the past, and put a fair amount of stress on our 80 ton press, from time to time. Pulling the gears off with a gear puller has also resulted in broken gears with some DIY members. This really is not the easiest gearbox to work on.
Take care not to put too much heat into the box as well, as this will end badly and cost a lot more in the long run.
If anyone has questions or has a need for bearings let me know. I am always here to help.
Erik Johnson - (720) 899-6005
Take care not to put too much heat into the box as well, as this will end badly and cost a lot more in the long run.
If anyone has questions or has a need for bearings let me know. I am always here to help.
Erik Johnson - (720) 899-6005
Thank's
01-16-2017, 12:09 AM
#33
Drifting
01-16-2017, 11:22 AM
#35
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01-16-2017, 11:55 PM
#37
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Here on the first photo the bolt that I had to remove to be able to take off the nose cone. Maybe in Nick's instructions he did'nt mentioned it cause the assembly that it holds inside (second photo) came with his cone. In my case I was able to lift the cone only about 3/4 of an inch.
I reinstalled the bolt and the small shaft and gear assembly in the nose cone for reassembly later.
I reinstalled the bolt and the small shaft and gear assembly in the nose cone for reassembly later.
01-17-2017, 09:43 AM
#38
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Here on the first photo the bolt that I had to remove to be able to take off the nose cone. Maybe in Nick's instructions he did'nt mentioned it cause the assembly that it holds inside (second photo) came with his cone. In my case I was able to lift the cone only about 3/4 of an inch.
I reinstalled the bolt and the small shaft and gear assembly in the nose cone for reassembly later.
I reinstalled the bolt and the small shaft and gear assembly in the nose cone for reassembly later.
01-17-2017, 01:37 PM
#40
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01-17-2017, 11:44 PM
#41
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Here are some photos of the shafts and gears of my C4 tranny.
The shaft of a C4 is not hollow? The end of it where I will have to apply pressure is only about 1/2 of an inch. Will it be ok?
Is it possible to separate the shafts earlier in the procedure like at the beginning? It would be easier to remove gears with jigs I could make to work on the press instead of a puller.
Thank's in advance Nick.
The shaft of a C4 is not hollow? The end of it where I will have to apply pressure is only about 1/2 of an inch. Will it be ok?
Is it possible to separate the shafts earlier in the procedure like at the beginning? It would be easier to remove gears with jigs I could make to work on the press instead of a puller.
Thank's in advance Nick.
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gled (07-01-2021)
01-30-2017, 06:28 PM
#42
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Ok, I'll answer my question myself again. If ever it could help someone....
I finished removing the primary and secondary shaft from the tranny case and I don't see any reason to wait until some gears are off from the secondary shaft to remove the bearing of the primary one to separate both shafts. When separated I should be able to remove everything from the secondary shaft by pressing instead of using a puller.
To be continued...
I finished removing the primary and secondary shaft from the tranny case and I don't see any reason to wait until some gears are off from the secondary shaft to remove the bearing of the primary one to separate both shafts. When separated I should be able to remove everything from the secondary shaft by pressing instead of using a puller.
To be continued...
02-03-2017, 11:17 PM
#45
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Latest news. I just finished pressing everything out from the secondary shaft. I succeeded with a max pressure of 25 tons. No problems at all. The bearing was out of grease which I never found inside. Probably because the previous owner had the transmission opened and got afraid of the job and closed it back like that but took away Porsche's magic grease before.
On the photo we can see the spot on the bearing race. It makes it sure that it was really the cause of the tranny noise.
As soon as I can I will make another thread on the complete disassembly of C4 transmission with a few tricks I found and used. With Nick Hends DIY it could help very much
On the photo we can see the spot on the bearing race. It makes it sure that it was really the cause of the tranny noise.
As soon as I can I will make another thread on the complete disassembly of C4 transmission with a few tricks I found and used. With Nick Hends DIY it could help very much