Author |
Message |
Carl Heydon
Frequent User Username: car
Post Number: 64 Registered: 2-2004
| Posted on Thursday, 22 January, 2015 - 06:52: | |
OK, B229FU was dismantled in 1977 after the ride control hose emptied the gearbox oil and damaged the bearings. All the gears appear unmarked and a complete set of bearings should arrive today . Does anyone have advice or warnings? Carl |
Carl Heydon
Frequent User Username: car
Post Number: 65 Registered: 2-2004
| Posted on Wednesday, 28 January, 2015 - 17:38: | |
David Hughes, I sent you a message in reply but it bounced. You may want to check your details. |
David Hughes
Experienced User Username: wedcar
Post Number: 48 Registered: 7-2004
| Posted on Tuesday, 10 February, 2015 - 15:06: | |
Hi Carl Thank you for your post - I did not receive the private message, however profile details are OK. Regards David |
Chis Carnley
Unregistered guest Posted From: 86.168.246.188
| Posted on Wednesday, 11 February, 2015 - 00:44: | |
Please do not use standard 6300 round edged bearings for the 1st motion shaft or the end of the 3rd motion shaft, as the square edges of the original 4 point contact bearings were to prevent the snap rings breaking, and they do! It is total nonsense to suggest that R-R have rescinded this detail even though JB are only supplying standards.
(Message approved by david_gore) |
Carl Heydon
Frequent User Username: car
Post Number: 67 Registered: 2-2004
| Posted on Sunday, 22 February, 2015 - 06:57: | |
Thanks Chris, But it went in that same week with standard bearings. Of course I found the info about fitting larger snap rings after it was back on the road. Hugely quieter now, still a slight whine in intermediate gears but nothing like B14BH which had a random countershaft fitted sometime in the past(the 'fitter' didn't think the broken teeth needed to be removed from the box. There was even a woodruff key in there!) Anyway, what is the risk of breakage? Should I pull it out again? I used Loctite shaft fit on the bearing and snapring. Does anyone else have input? Thanks Carl |
christopher carnley
Unregistered guest Posted From: 86.173.13.86
| Posted on Tuesday, 24 February, 2015 - 04:54: | |
Hi, The standard bearings are wrong for two reasons, they are deep groove for radial loads only, the correct bearings are 4 point contact or (double angular) for the considerable axial loads from the extreme helical gearing and end loading. The bigger snap ring will suffice only for the front bearing and this snap ring , originally, was quite narrow. As the aluminium rear housing heats up quite considerably in use, the bearing register expands and the diameter increases, negating the sealant. All rear bearings inspected show that the outer "fixed" ring rotates quite easily. The round edge bends and then breaks the snap ring under the overrun effect, and then the protruding bearing jams the front 3rd/4th speed synchros. I have removed several from later "Factory" overhauls, as they had run out of the correct ones, and "It fills the hole and makes a job". I have also removed standards from gearboxes rebuilt for the leading UK specialist on the Bentley Continental cars. What was the condition of the 3rd speed splined thrust washer, a very brittle item, and is it the original .175" thick one? The original square edge ones can be reconditioned, but I have new rear ones made by HB Bearings.
(Message approved by david_gore) |
|