Indicator cancelling boss thread
- gs.davies
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Indicator cancelling boss thread
I’ve had to fit a new rack to my car and it seems that the pinion has the half moon cut out to locate the column and it’s now positioned as per a ‘modern’ car. This means the self cancelling boss is in the wrong place.
Does anyone know what thread this should be so I can redrill it and put it in the right place to suit the rack?
Thanks
Gary
Does anyone know what thread this should be so I can redrill it and put it in the right place to suit the rack?
Thanks
Gary
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- 1275 Cooper S
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Re: Indicator cancelling boss thread
Had same issues with a new ( but in my stock for some years ) Steering Rack ..mine was assembled out of phase therefore the half moon is out of position.. i centered rack & ground a new half moon in correct position ( clamp bolt horizontal ) so trafficator works correctly .. worked for me .
- Peter Laidler
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Re: Indicator cancelling boss thread
Ah, yes...... The wrong radial position of the steering column clamp bolt recess or half-moon means that the rack hasn't been assembled correctly.
When assembling a Mk2 type rack, the pinion can be assembled in any one of 6(?) positions. Only ONE such position is correct. And yours ain't!
I'm not sure that I'd be drilling yet another hole in the steering column Gary (unlike drilling through the actual rack) because whereas the loading on the rack is linear, on the column, it's radial. And you already have a partial hole there already.. But that's just me.
Like Norman suggests. You could just grind a new half moon. Or do what I did to a couple of hybrid mix an' match racks. Just machine the half-moon all the way around the pinion
When assembling a Mk2 type rack, the pinion can be assembled in any one of 6(?) positions. Only ONE such position is correct. And yours ain't!
I'm not sure that I'd be drilling yet another hole in the steering column Gary (unlike drilling through the actual rack) because whereas the loading on the rack is linear, on the column, it's radial. And you already have a partial hole there already.. But that's just me.
Like Norman suggests. You could just grind a new half moon. Or do what I did to a couple of hybrid mix an' match racks. Just machine the half-moon all the way around the pinion
- gs.davies
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Re: Indicator cancelling boss thread
I'm way past being able to easily remove the rack now. Engine is in, brakes are in, it's almost ready to run..Peter Laidler wrote: ↑Wed Mar 08, 2023 12:08 pm Ah, yes...... The wrong radial position of the steering column clamp bolt recess or half-moon means that the rack hasn't been assembled correctly.
When assembling a Mk2 type rack, the pinion can be assembled in any one of 6(?) positions. Only ONE such position is correct. And yours ain't!
I'm not sure that I'd be drilling yet another hole in the steering column Gary (unlike drilling through the actual rack) because whereas the loading on the rack is linear, on the column, it's radial. And you already have a partial hole there already.. But that's just me.
Like Norman suggests. You could just grind a new half moon. Or do what I did to a couple of hybrid mix an' match racks. Just machine the half-moon all the way around the pinion
Maybe I'll just live with it not self cancelling, it rarely ever worked thirty years ago when it was last on the road!
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Re: Indicator cancelling boss thread
My solution was to get the Dremel out & grind the Half Moon with the Rack all bolted in position.. was no big issue & there is no need to cut away such a big half moon as all that is needed is enough clearance to get the clamp bolt in & the Colum to clamp up secure 

- Peter Laidler
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Re: Indicator cancelling boss thread
I understand all that Norman and Gary.
One other interesting point about that half moon (Mk2) or groove (Mk1) is that it is a safety related feature. Or a MECHANICAL SAFETY. According to the Cam Gears rep, the half moon/groove position along the pinion was such that the steering column and wheel would not position correctly unless the column was pushed right down on the pinion and the slot aligned with the bolt hole in the column. This ensures full engagement of the splines. The second safety feature to back this up was the bolt that will not allow the column to disengage from the pinion.
When I passed the article about refurbishing the racks under his eyes, he recommended fitting a new bolt and nyloc each time!
One other interesting point about that half moon (Mk2) or groove (Mk1) is that it is a safety related feature. Or a MECHANICAL SAFETY. According to the Cam Gears rep, the half moon/groove position along the pinion was such that the steering column and wheel would not position correctly unless the column was pushed right down on the pinion and the slot aligned with the bolt hole in the column. This ensures full engagement of the splines. The second safety feature to back this up was the bolt that will not allow the column to disengage from the pinion.
When I passed the article about refurbishing the racks under his eyes, he recommended fitting a new bolt and nyloc each time!
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Re: Indicator cancelling boss thread
Clear the fault lies with the assembly of the steering rack.. suppliers Quality cannot be trusted & its up to me the installer to "Center" the Mk1 Steering Rack "Before " it is fitted to ensure the Half Moon on the input spline shaft is at the bottom .. Buyer Beware in my case 

- gs.davies
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Re: Indicator cancelling boss thread
I am determined not to have to pull the rack.
If I leave it where the half moon is positioned at the moment (around 2 o clock) what’s the implications?
If I leave it where the half moon is positioned at the moment (around 2 o clock) what’s the implications?
- Peter Laidler
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Re: Indicator cancelling boss thread
Leave it at 2 o'clock.... As I see it, it'll still cancel but it'll cancel sooner one way than the other. Nothing serious. But you might as well file out another half moon to suit, as Norman did.
- gs.davies
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Re: Indicator cancelling boss thread
Am I being dim, but surely filing out another slot for the pinch bolt is more likely to go wrong and cause trouble than drilling a new hole for the cancelling boss..? What am I missing?