4G Mk1 rockers

[Duncan J Robertson]

Can anyone advise which are the correct rockers for a MK1 with regard to the oil holes drilled, or otherwise.
I have 5 variations on mine out of the 8, is this a record for different rockers.

No holes
Drilled center rib
Drilled center rib and short side
Drilled center rib and long side
Drilled short side only

I fit the spindle with the supply holes facing down

[paul.jameson]

There is a photo on P19 of Square Forum which may help. I assume that there is a copy of this AOMCC produced book somewhere on the website but if all else fails I may be ale to scan the original proof for you.

[Duncan J Robertson]

Thanks Paul
What does P19 refer to, I can't find any links.
The Ariel manual !948-1958 shows a central drilled hole, also details of how to solve over oiling etc. so I assume they should all be centre drilled, and no others

[paul.jameson]

To my surprise, I can't find a copy of Square Forum on the website. I will send a copy to the webmaster. It was written by John Bradshaw (ex -Chairman), the late Ralph Hawkins (ex - Archivist) and Mike Macdonald (ex Square Four Spares Organiser) and published by the AOMCC in 1987. It does contain much useful information although our knowledge of the machines has improved over the past 40 years as experience has been gained and shared via Cheval de Fer.

I have tried to produce a decent image for you from the original proofs and failed. So I have scanned my copy of the document and played with it in Photoshop which has eventually given something which may be of use. I will attach it to this post. When you look at it, note the changes in profile of the rockers visible in the side view as well as the only oil hole I can see which is on the Mk I rocker in the centre. There may, of course, be other versions of the rockers not illustrated here.

[Duncan J Robertson]

Thanks for your efforts Paul, much appreciated.
Thought there should only be a single oil hole in the rocker, my machines top end was obviously built from a box of bits.
I have a set of 8 with no holes, the same profile as the 4G ones in the picture, going to get 4 of them drilled

[Chris Sealy]

I have also found variations in rockers. No oil hole at all. Oil hole drilled vertically. Oil hole drilled at an angle. See photos.
The only one with the Ariel part number ET 1306 cast on it, is the one with the oil hole drilled at an angle. That is the only one that I use. I have put a piece of wire into the oil holes to show the angle of the drilling.

[Duncan J Robertson]

It never occurred to me the holes would be at an angle, on checking the four of mine drilled with a single hole, they were all at an angle.
Thanks for the head up on this.
Looking at the picture from Paul, your two rockers on the left are from a 4G and the one on the right is a MK1
My assumption for the angled drilling is to reduce the over oiling described in the Ariel workshop manual, and the need to grind the sides out of the rockers.