Bishops Cam Steering 'O' Rings & Oil

[m_e_jablonski]

I'm in the process of servicing my Bishops Cam steering box and have a few questions for those of you still using this box.  

[*]On the shaft (inside the steering column) I have three rubber 'O' rings, two are a close fit on the shaft and the other is slightly larger.  One of the two smaller rings is a normal 'O' ring while the other has a square cross section.  I'm assuming that these 'O' rings were intended to limit flexing of the shaft and should be located halfway down the shaft.  There's a slightly lumpy patch of green paint about halfway along the shaft and my suspicion is that this was intended to keep at least one of the rings from sliding downwards.  Has anyone else seen these rings/paint patches and are my assumptions correct?  Doug Pelton's FTFU catalog lists one rubber anti-rattle ring. [*]The larger 'O' ring is too loose to stay put on the shaft but there is a groove below the steering wheel splines, at the bottom of the smooth section where the felt bush locates and the 'O' ring is a tight fit into this groove.  Would this be to help retain the oil in the felt bush? [*]Up to now I've been using Penrite Transoil 140 mixed with molybdenum disulphide in the steering box.  Despite having an oil seal around the sector shaft and a felt seal below that, the oil drips out of the box.  I've wondered about using Transoil 250, which is a lot thicker and should help slow the leak.  What does the group think about using this oil?  My concern is that not enough of it will find its way down to lubricate the sector shaft.  

And finally an observation - when I originally rebuilt the box I inserted a sheet of phosphor bronze between the lid and the top of the sector shaft.  I had the top of the sector shaft ground smooth and rounded off the corners.  After about 14.5K miles there is very little wear on the bronze sheet - as near as I could measure, about 1/3 of a thou.  Mark Jablonski Melbourne Australia

[Clive Sherriff]

These rubber O Rings are non standard. there should be just a felt insert at the top of the shaft by the steering wheel. Re the steering box oil, with a big leak, the clearances on the sector shaft may be just too great and the box needs a new / reconditioned sector shaft and rebushing. EP90 or EP140 oil is right, 250 too "stiff" ~ you have to lubricate the worm too and the 250 is too thick to slosh about and do that adequately. Today we get paranoid about oil leaks, but in the 1930s and 40s these boxes were specifically designed without an oil seal precisely to allow the oil to flow along the sector shaft. The oil would pick up small traces of metal as it turned in the box housing, so was allowed to leak out of the bottom and be replaced by new clean oil from the main reservoir of oil in the upper part of the box, around the worm. If it did not drip out then it would just turn into grinding paste. Indeed I have known a recon box with a close fitting sector shaft and an over efficient oil seal fitted, to lock up as the oil around the shaft did become clogged with metal which turned into a paste and jammed the shaft. Fitting an effective oil seal greatly reduces the life of the box ! Clive Oxford, UK. M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com

On Sun, 2 Jun 2019 at 13:58, m.jablonski@jablonski.net.au [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] I'm in the process of servicing my Bishops Cam steering box and have a few questions for those of you still using this box.

[*]On the shaft (inside the steering column) I have three rubber 'O' rings, two are a close fit on the shaft and the other is slightly larger. One of the two smaller rings is a normal 'O' ring while the other has a square cross section. I'm assuming that these 'O' rings were intended to limit flexing of the shaft and should be located halfway down the shaft. There's a slightly lumpy patch of green paint about halfway along the shaft and my suspicion is that this was intended to keep at least one of the rings from sliding downwards. Has anyone else seen these rings/paint patches and are my assumptions correct? Doug Pelton's FTFU catalog lists one rubber anti-rattle ring. [*]The larger 'O' ring is too loose to stay put on the shaft but there is a groove below the steering wheel splines, at the bottom of the smooth section where the felt bush locates and the 'O' ring is a tight fit into this groove. Would this be to help retain the oil in the felt bush? [*]Up to now I've been using Penrite Transoil 140 mixed with molybdenum disulphide in the steering box. Despite having an oil seal around the sector shaft and a felt seal below that, the oil drips out of the box. I've wondered about using Transoil 250, which is a lot thicker and should help slow the leak. What does the group think about using this oil? My concern is that not enough of it will find its way down to lubricate the sector shaft.

And finally an observation - when I originally rebuilt the box I inserted a sheet of phosphor bronze between the lid and the top of the sector shaft. I had the top of the sector shaft ground smooth and rounded off the corners. After about 14.5K miles there is very little wear on the bronze sheet - as near as I could measure, about 1/3 of a thou. Mark Jablonski Melbourne Australia

[img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com

[jeffrey townsend]

Hello Clive, An interesting point. I d never thought before about the need for the oil to leak from the steering box to remove metal particles. There is no drain plug so I expect you are correct.  I don t worry too much about oil on the garage floor but do wonder sometimes about it s origin as the steering oil does spread itself around as it clings to the car when on the move and drips off when back in the garage. Also when stationary it runs down the track rods raising the question is it from the engine, trunnions or steering. Quantities are not great and a broadsheet newspaper is my answer.  Called recently to see a cousin on the way back from the TB80 event (it was a great success and we missed you). He has a very smart block paved drive. I warned him about oil drips but he wasn t bothered. On leaving about 3 hours later there were no oil drips which was good but I worried then that there was oil in the steering. We d done about 500 miles. Checked when home and all was OK.  Away from the above ramble one slightly technical point from your email. You mention the possible need to rebush. My understanding is that the boxes didn t have bushes from new.  Regards  Jeff.   N Cambs. UK TA1957 TB0489 Sent from my iPhone

On 2 Jun 2019, at 23:07, CLIVE SHERRIFF csherriff99@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote:

  These rubber O Rings are non standard. there should be just a felt insert  at the top of the shaft by the steering wheel. Re the steering box oil, with a big leak, the clearances on the sector shaft may  be just too great and the box needs a new / reconditioned sector shaft and  rebushing.   EP90 or EP140 oil is right, 250 too "stiff" ~ you have to lubricate  the worm too and the 250 is too thick to slosh about and do that adequately. Today we get paranoid about oil leaks, but in the 1930s and 40s these boxes  were specifically designed without an oil seal precisely to allow the oil to flow along  the sector shaft.  The oil would pick up small traces of metal as it turned in the box  housing, so was allowed to leak out of the bottom and be replaced by new clean oil  from the main reservoir of oil in the upper part of the box, around the worm.  If it did  not drip out then it would just turn into grinding paste.  Indeed I have known a recon  box with a close fitting sector shaft and an over efficient oil seal fitted, to lock up  as the oil around the shaft did become clogged with metal which turned into a paste  and jammed the shaft. Fitting an effective oil seal greatly reduces the life of the box ! Clive Oxford, UK. M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com On Sun, 2 Jun 2019 at 13:58, m.jablonski@jablonski.net.au [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u]   I'm in the process of servicing my Bishops Cam steering box and have a few questions for those of you still using this box.  

[*]On the shaft (inside the steering column) I have three rubber 'O' rings, two are a close fit on the shaft and the other is slightly larger.  One of the two smaller rings is a normal 'O' ring while the other has a square cross section.  I'm assuming that these 'O' rings were intended to limit flexing of the shaft and should be located halfway down the shaft.  There's a slightly lumpy patch of green paint about halfway along the shaft and my suspicion is that this was intended to keep at least one of the rings from sliding downwards.  Has anyone else seen these rings/paint patches and are my assumptions correct?  Doug Pelton's FTFU catalog lists one rubber anti-rattle ring. [*]The larger 'O' ring is too loose to stay put on the shaft but there is a groove below the steering wheel splines, at the bottom of the smooth section where the felt bush locates and the 'O' ring is a tight fit into this groove.  Would this be to help retain the oil in the felt bush? [*]Up to now I've been using Penrite Transoil 140 mixed with molybdenum disulphide in the steering box.  Despite having an oil seal around the sector shaft and a felt seal below that, the oil drips out of the box.  I've wondered about using Transoil 250, which is a lot thicker and should help slow the leak.  What does the group think about using this oil?  My concern is that not enough of it will find its way down to lubricate the sector shaft.  

And finally an observation - when I originally rebuilt the box I inserted a sheet of phosphor bronze between the lid and the top of the sector shaft.  I had the top of the sector shaft ground smooth and rounded off the corners.  After about 14.5K miles there is very little wear on the bronze sheet - as near as I could measure, about 1/3 of a thou.  Mark Jablonski Melbourne Australia [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com

[Clive Sherriff]

Jeff, Yes, you are right, the boxes were not originally bushed so "rebushed" was a bit inaccurate (first time round anyway !). Steel running on cast iron is a natural lubricant anyway, even without oil, largely due to the carbon/graphite particles in the cast iron matrix, so when new, no bronze bush is in fact better than having a bush, especially when augmented by the ongoing "total loss" oil flow down the shaft which gets rid of the dross. Bronze bushes when fitted need to be the whole length of the shaft to spread the loads, not just an inch top and bottom, and do wear quite quickly as there are quite heavy loads put on them and sintered bushes can break up rapidly so don't use those. Depending how badly worn the box is, the best first repair would be to fractionally bore the box a few thou' oversize, and have a sector shaft with an oversized shaft between the peg end and the spline. This can be either a special oversized shaft (I've not seen any for decades) or done by hard chroming a used shaft with a good spline, (or using a new shaft) and grinding that to suit the new box diameter. Clive Oxford, UK M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm

On Mon, 3 Jun 2019 at 07:42, jeffrey townsend jeff.townsend@hotmail.co.uk> wrote: Hello Clive, An interesting point. I d never thought before about the need for the oil to leak from the steering box to remove metal particles. There is no drain plug so I expect you are correct. I don t worry too much about oil on the garage floor but do wonder sometimes about it s origin as the steering oil does spread itself around as it clings to the car when on the move and drips off when back in the garage. Also when stationary it runs down the track rods raising the question is it from the engine, trunnions or steering. Quantities are not great and a broadsheet newspaper is my answer. Called recently to see a cousin on the way back from the TB80 event (it was a great success and we missed you). He has a very smart block paved drive. I warned him about oil drips but he wasn t bothered. On leaving about 3 hours later there were no oil drips which was good but I worried then that there was oil in the steering. We d done about 500 miles. Checked when home and all was OK. Away from the above ramble one slightly technical point from your email. You mention the possible need to rebush. My understanding is that the boxes didn t have bushes from new. Regards Jeff. N Cambs. UK TA1957 TB0489 Sent from my iPhone On 2 Jun 2019, at 23:07, CLIVE SHERRIFF csherriff99@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: These rubber O Rings are non standard. there should be just a felt insert at the top of the shaft by the steering wheel. Re the steering box oil, with a big leak, the clearances on the sector shaft may be just too great and the box needs a new / reconditioned sector shaft and rebushing. EP90 or EP140 oil is right, 250 too "stiff" ~ you have to lubricate the worm too and the 250 is too thick to slosh about and do that adequately. Today we get paranoid about oil leaks, but in the 1930s and 40s these boxes were specifically designed without an oil seal precisely to allow the oil to flow along the sector shaft. The oil would pick up small traces of metal as it turned in the box housing, so was allowed to leak out of the bottom and be replaced by new clean oil from the main reservoir of oil in the upper part of the box, around the worm. If it did not drip out then it would just turn into grinding paste. Indeed I have known a recon box with a close fitting sector shaft and an over efficient oil seal fitted, to lock up as the oil around the shaft did become clogged with metal which turned into a paste and jammed the shaft. Fitting an effective oil seal greatly reduces the life of the box ! Clive Oxford, UK. M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com On Sun, 2 Jun 2019 at 13:58, m.jablonski@jablonski.net.au [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] I'm in the process of servicing my Bishops Cam steering box and have a few questions for those of you still using this box.

[*]On the shaft (inside the steering column) I have three rubber 'O' rings, two are a close fit on the shaft and the other is slightly larger. One of the two smaller rings is a normal 'O' ring while the other has a square cross section. I'm assuming that these 'O' rings were intended to limit flexing of the shaft and should be located halfway down the shaft. There's a slightly lumpy patch of green paint about halfway along the shaft and my suspicion is that this was intended to keep at least one of the rings from sliding downwards. Has anyone else seen these rings/paint patches and are my assumptions correct? Doug Pelton's FTFU catalog lists one rubber anti-rattle ring. [*]The larger 'O' ring is too loose to stay put on the shaft but there is a groove below the steering wheel splines, at the bottom of the smooth section where the felt bush locates and the 'O' ring is a tight fit into this groove. Would this be to help retain the oil in the felt bush? [*]Up to now I've been using Penrite Transoil 140 mixed with molybdenum disulphide in the steering box. Despite having an oil seal around the sector shaft and a felt seal below that, the oil drips out of the box. I've wondered about using Transoil 250, which is a lot thicker and should help slow the leak. What does the group think about using this oil? My concern is that not enough of it will find its way down to lubricate the sector shaft.

And finally an observation - when I originally rebuilt the box I inserted a sheet of phosphor bronze between the lid and the top of the sector shaft. I had the top of the sector shaft ground smooth and rounded off the corners. After about 14.5K miles there is very little wear on the bronze sheet - as near as I could measure, about 1/3 of a thou. Mark Jablonski Melbourne Australia

[img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com

[Clive Sherriff]

Jeff, Yes, you are right, the boxes were not originally bushed so "rebushed" was a bit inaccurate (first time round anyway !). Steel running on cast iron is a natural lubricant anyway, even without oil, largely due to the carbon/graphite particles in the cast iron matrix, so when new, no bronze bush is in fact better than having a bush, especially when augmented by the ongoing "total loss" oil flow down the shaft which gets rid of the dross. Bronze bushes when fitted need to be the whole length of the shaft to spread the loads, not just an inch top and bottom, and do wear quite quickly as there are quite heavy loads put on them and sintered bushes can break up rapidly so don't use those. Depending how badly worn the box is, the best first repair would be to fractionally bore the box a few thou' oversize, and have a sector shaft with an oversized shaft between the peg end and the spline. This can be either a special oversized shaft (I've not seen any for decades) or done by hard chroming a used shaft with a good spline, (or using a new shaft) and grinding that to suit the new box diameter. Clive Oxford, UK M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm

On Mon, 3 Jun 2019 at 07:42, jeffrey townsend jeff.townsend@hotmail.co.uk> wrote: Hello Clive, An interesting point. I d never thought before about the need for the oil to leak from the steering box to remove metal particles. There is no drain plug so I expect you are correct. I don t worry too much about oil on the garage floor but do wonder sometimes about it s origin as the steering oil does spread itself around as it clings to the car when on the move and drips off when back in the garage. Also when stationary it runs down the track rods raising the question is it from the engine, trunnions or steering. Quantities are not great and a broadsheet newspaper is my answer. Called recently to see a cousin on the way back from the TB80 event (it was a great success and we missed you). He has a very smart block paved drive. I warned him about oil drips but he wasn t bothered. On leaving about 3 hours later there were no oil drips which was good but I worried then that there was oil in the steering. We d done about 500 miles. Checked when home and all was OK. Away from the above ramble one slightly technical point from your email. You mention the possible need to rebush. My understanding is that the boxes didn t have bushes from new. Regards Jeff. N Cambs. UK TA1957 TB0489 Sent from my iPhone On 2 Jun 2019, at 23:07, CLIVE SHERRIFF csherriff99@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: These rubber O Rings are non standard. there should be just a felt insert at the top of the shaft by the steering wheel. Re the steering box oil, with a big leak, the clearances on the sector shaft may be just too great and the box needs a new / reconditioned sector shaft and rebushing. EP90 or EP140 oil is right, 250 too "stiff" ~ you have to lubricate the worm too and the 250 is too thick to slosh about and do that adequately. Today we get paranoid about oil leaks, but in the 1930s and 40s these boxes were specifically designed without an oil seal precisely to allow the oil to flow along the sector shaft. The oil would pick up small traces of metal as it turned in the box housing, so was allowed to leak out of the bottom and be replaced by new clean oil from the main reservoir of oil in the upper part of the box, around the worm. If it did not drip out then it would just turn into grinding paste. Indeed I have known a recon box with a close fitting sector shaft and an over efficient oil seal fitted, to lock up as the oil around the shaft did become clogged with metal which turned into a paste and jammed the shaft. Fitting an effective oil seal greatly reduces the life of the box ! Clive Oxford, UK. M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com On Sun, 2 Jun 2019 at 13:58, m.jablonski@jablonski.net.au [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] I'm in the process of servicing my Bishops Cam steering box and have a few questions for those of you still using this box.

[*]On the shaft (inside the steering column) I have three rubber 'O' rings, two are a close fit on the shaft and the other is slightly larger. One of the two smaller rings is a normal 'O' ring while the other has a square cross section. I'm assuming that these 'O' rings were intended to limit flexing of the shaft and should be located halfway down the shaft. There's a slightly lumpy patch of green paint about halfway along the shaft and my suspicion is that this was intended to keep at least one of the rings from sliding downwards. Has anyone else seen these rings/paint patches and are my assumptions correct? Doug Pelton's FTFU catalog lists one rubber anti-rattle ring. [*]The larger 'O' ring is too loose to stay put on the shaft but there is a groove below the steering wheel splines, at the bottom of the smooth section where the felt bush locates and the 'O' ring is a tight fit into this groove. Would this be to help retain the oil in the felt bush? [*]Up to now I've been using Penrite Transoil 140 mixed with molybdenum disulphide in the steering box. Despite having an oil seal around the sector shaft and a felt seal below that, the oil drips out of the box. I've wondered about using Transoil 250, which is a lot thicker and should help slow the leak. What does the group think about using this oil? My concern is that not enough of it will find its way down to lubricate the sector shaft.

And finally an observation - when I originally rebuilt the box I inserted a sheet of phosphor bronze between the lid and the top of the sector shaft. I had the top of the sector shaft ground smooth and rounded off the corners. After about 14.5K miles there is very little wear on the bronze sheet - as near as I could measure, about 1/3 of a thou. Mark Jablonski Melbourne Australia

[img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com

[Roger Furneaux]

hi Clive - the VW boxes have a very sticky black grease in them, which would certainly not allow the worm to run dry! Many moons ago when we had this discussion, one of our American cousins said he used a Ford 600 grade oil, which may be equivalent to the VW goo. Hard-chroming the shaft is certainly the way to go: I had mine done by the late Ray Sales, and last time I took it out, there was absolutely no wear on the shaft or the bushes. I have an unbushed BC box from my first car, a 1935 Morris 8, and my plan is to build it up and experience what things were like when new... RogerDevon Olde England

On Mon, Jun 3, 2019 at 9:16 AM CLIVE SHERRIFF csherriff99@gmail.com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] Jeff, Yes, you are right, the boxes were not originally bushed so "rebushed" was a bit inaccurate (first time round anyway !). Steel running on cast iron is a natural lubricant anyway, even without oil, largely due to the carbon/graphite particles in the cast iron matrix, so when new, no bronze bush is in fact better than having a bush, especially when augmented by the ongoing "total loss" oil flow down the shaft which gets rid of the dross. Bronze bushes when fitted need to be the whole length of the shaft to spread the loads, not just an inch top and bottom, and do wear quite quickly as there are quite heavy loads put on them and sintered bushes can break up rapidly so don't use those. Depending how badly worn the box is, the best first repair would be to fractionally bore the box a few thou' oversize, and have a sector shaft with an oversized shaft between the peg end and the spline. This can be either a special oversized shaft (I've not seen any for decades) or done by hard chroming a used shaft with a good spline, (or using a new shaft) and grinding that to suit the new box diameter. Clive Oxford, UK M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm On Mon, 3 Jun 2019 at 07:42, jeffrey townsend jeff.townsend@hotmail.co.uk> wrote: Hello Clive, An interesting point. I d never thought before about the need for the oil to leak from the steering box to remove metal particles. There is no drain plug so I expect you are correct. I don t worry too much about oil on the garage floor but do wonder sometimes about it s origin as the steering oil does spread itself around as it clings to the car when on the move and drips off when back in the garage. Also when stationary it runs down the track rods raising the question is it from the engine, trunnions or steering. Quantities are not great and a broadsheet newspaper is my answer. Called recently to see a cousin on the way back from the TB80 event (it was a great success and we missed you). He has a very smart block paved drive. I warned him about oil drips but he wasn t bothered. On leaving about 3 hours later there were no oil drips which was good but I worried then that there was oil in the steering.. We d done about 500 miles. Checked when home and all was OK. Away from the above ramble one slightly technical point from your email. You mention the possible need to rebush. My understanding is that the boxes didn t have bushes from new. Regards Jeff. N Cambs. UK TA1957 TB0489 Sent from my iPhone On 2 Jun 2019, at 23:07, CLIVE SHERRIFF csherriff99@gmail..com [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: These rubber O Rings are non standard. there should be just a felt insert at the top of the shaft by the steering wheel. Re the steering box oil, with a big leak, the clearances on the sector shaft may be just too great and the box needs a new / reconditioned sector shaft and rebushing. EP90 or EP140 oil is right, 250 too "stiff" ~ you have to lubricate the worm too and the 250 is too thick to slosh about and do that adequately. Today we get paranoid about oil leaks, but in the 1930s and 40s these boxes were specifically designed without an oil seal precisely to allow the oil to flow along the sector shaft. The oil would pick up small traces of metal as it turned in the box housing, so was allowed to leak out of the bottom and be replaced by new clean oil from the main reservoir of oil in the upper part of the box, around the worm. If it did not drip out then it would just turn into grinding paste. Indeed I have known a recon box with a close fitting sector shaft and an over efficient oil seal fitted, to lock up as the oil around the shaft did become clogged with metal which turned into a paste and jammed the shaft. Fitting an effective oil seal greatly reduces the life of the box ! Clive Oxford, UK. M mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm [img]https://ec.yimg.com/ec?url=https%3A%2F%2Fipmcdn.avast.com%2Fimages%2Ficons%2Ficon-envelope-tick-round-orange-animated-no-repeat-v1.gif&t=1560026313&sig=Q3VQ33woOoVPRwei2cyirw--~D[/img] Virus-free. www.avast.com On Sun, 2 Jun 2019 at 13:58, m.jablonski@jablonski.net.au [mg-tabc] mg-tabc-noreply@yahoogroups.com> wrote: [u][/u] I'm in the process of servicing my Bishops Cam steering box and have a few questions for those of you still using this box.

[*]On the shaft (inside the steering column) I have three rubber 'O' rings, two are a close fit on the shaft and the other is slightly larger. One of the two smaller rings is a normal 'O' ring while the other has a square cross section. I'm assuming that these 'O' rings were intended to limit flexing of the shaft and should be located halfway down the shaft. There's a slightly lumpy patch of green paint about halfway along the shaft and my suspicion is that this was intended to keep at least one of the rings from sliding downwards. Has anyone else seen these rings/paint patches and are my assumptions correct? Doug Pelton's FTFU catalog lists one rubber anti-rattle ring. [*]The larger 'O' ring is too loose to stay put on the shaft but there is a groove below the steering wheel splines, at the bottom of the smooth section where the felt bush locates and the 'O' ring is a tight fit into this groove. Would this be to help retain the oil in the felt bush? [*]Up to now I've been using Penrite Transoil 140 mixed with molybdenum disulphide in the steering box. Despite having an oil seal around the sector shaft and a felt seal below that, the oil drips out of the box. I've wondered about using Transoil 250, which is a lot thicker and should help slow the leak. What does the group think about using this oil? My concern is that not enough of it will find its way down to lubricate the sector shaft.

And finally an observation - when I originally rebuilt the box I inserted a sheet of phosphor bronze between the lid and the top of the sector shaft. I had the top of the sector shaft ground smooth and rounded off the corners. After about 14.5K miles there is very little wear on the bronze sheet - as near as I could measure, about 1/3 of a thou. Mark Jablonski Melbourne Australia

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[m_e_jablonski]

Thanks to all who replied to my query.  It looks like the consensus is not to use a heavier oil in the BC box in order to keep the sector shaft lubricated.  So I'll stick with the 140 grade oil.  It looks like the 'O' rings on the shaft are unoriginal, so it makes no difference where I put them if I decide to leave them there.  Eric Worpe made an interesting point - that I should be wary of adjusting a worn peg as the step on the peg can cause the corners of the worm to spall.  I'll be checking the peg closely and replacing it if there's any doubt.  Duncan pointed out that excessive wear between the sector shaft and the bore can result in increased leakage past the seal.  I'll be checking that more closely too.  

 

Mark Jablonski

Melbourne Australia