billbayliner
Chief Petty Officer
- Joined
- Jun 30, 2006
- Messages
- 553
Re: 275 out drive ujoint question
Great video on the 280 transmission disassembly. It shows just how easy these are to work on. Looks like this is his very first time doing this and he's actually doing a great job.
He talks about the shims providing a pre-load.
FYI; think of this pre-load in a non-conventional sense in that these shims control the "squeeze" of this driven gear bearing to prevent it from rotating between the two housings.
These shims have nothing to do with any actual bearing rolling torque. These two driven gear bearings are angular contact bearings, not tapered roller bearings.
BTW, find all of these shims right off the bat. Like he shows, one or two might stick to and stay on the bearing. Find all of these and keep them marked and inventoried.
While he uses heat for the top cover..., we rarely have any trouble removing the three top cover cap screws or the hollow bolt.
NOTE: at 11 seconds into the video, the two threaded helmet pin bolt holes are shown.
If someone had installed the wrong bolts here (as in too long) the bolts will break open the aluminum casting at the interior bellows area (shown at 32 seconds), and water will find it's way into this area.
Check this carefully... it does happen.
At 9:57 into the video, note where he is applying heat. This is very important because this is where we find corrosion that can lock these threads up. Heat helps!
At 11:9 he has good luck... the BB pulls right out. Some need a bit or persuasion.
Once out, shims will be exposed.
At 11:56 he's picking the shims away from the BB shoulder. These will be rusty and delicate, so use caution.
At 13:25 the male yoke comes out. The seal surface may or may come out with it.. His did not!
At about 13:00 minutes in, you'd best start keeping very good track of the shims..... easy to get confused.
He hasn't noticed or mentioned the small main drive gear shims yet.
At 14:24 he mentions rust. This is typical of the pre "A" transmissions. You can do a better job when sealing this area.
At 14:53 he mentions that the O-ring is OK. All O-rings must be replaced... do not reuse any.
At 16:13 is your opportunity to press this gear out and take a look at the two bearings.
Finally at 17:02 he mentions the small main drive gear shims. Don't misplace these.
While he may not use the right description or language, the guy has a good mechanical aptitude and understanding.
Look carefully at 17:29. This is where rust ends up cutting away at the main seal.
Note 17:50.... he points out several locations for water intrusion.
At 18:17, we should have dry bellows regardless, but use sealant here.
OK... at 18:26 he opens up the possibility for a mistake.. but catches himself by saying that he'll mic the old and new part and adjust. Truth is he needs to check the rolling torque value and not rely on a micrometer reading. But he's on the right track.
This is the part that can be saved if not too badly rusted or corroded. Take a reading, polish it, take another reading. A few thou may save it.
Good video!
Great video on the 280 transmission disassembly. It shows just how easy these are to work on. Looks like this is his very first time doing this and he's actually doing a great job.
He talks about the shims providing a pre-load.
FYI; think of this pre-load in a non-conventional sense in that these shims control the "squeeze" of this driven gear bearing to prevent it from rotating between the two housings.
These shims have nothing to do with any actual bearing rolling torque. These two driven gear bearings are angular contact bearings, not tapered roller bearings.
BTW, find all of these shims right off the bat. Like he shows, one or two might stick to and stay on the bearing. Find all of these and keep them marked and inventoried.
While he uses heat for the top cover..., we rarely have any trouble removing the three top cover cap screws or the hollow bolt.
NOTE: at 11 seconds into the video, the two threaded helmet pin bolt holes are shown.
If someone had installed the wrong bolts here (as in too long) the bolts will break open the aluminum casting at the interior bellows area (shown at 32 seconds), and water will find it's way into this area.
Check this carefully... it does happen.
At 9:57 into the video, note where he is applying heat. This is very important because this is where we find corrosion that can lock these threads up. Heat helps!
At 11:9 he has good luck... the BB pulls right out. Some need a bit or persuasion.
Once out, shims will be exposed.
At 11:56 he's picking the shims away from the BB shoulder. These will be rusty and delicate, so use caution.
At 13:25 the male yoke comes out. The seal surface may or may come out with it.. His did not!
At about 13:00 minutes in, you'd best start keeping very good track of the shims..... easy to get confused.
He hasn't noticed or mentioned the small main drive gear shims yet.
At 14:24 he mentions rust. This is typical of the pre "A" transmissions. You can do a better job when sealing this area.
At 14:53 he mentions that the O-ring is OK. All O-rings must be replaced... do not reuse any.
At 16:13 is your opportunity to press this gear out and take a look at the two bearings.
Finally at 17:02 he mentions the small main drive gear shims. Don't misplace these.
While he may not use the right description or language, the guy has a good mechanical aptitude and understanding.
Look carefully at 17:29. This is where rust ends up cutting away at the main seal.
Note 17:50.... he points out several locations for water intrusion.
At 18:17, we should have dry bellows regardless, but use sealant here.
OK... at 18:26 he opens up the possibility for a mistake.. but catches himself by saying that he'll mic the old and new part and adjust. Truth is he needs to check the rolling torque value and not rely on a micrometer reading. But he's on the right track.
This is the part that can be saved if not too badly rusted or corroded. Take a reading, polish it, take another reading. A few thou may save it.
Good video!