More rocker spindle questions?

A while back I posted about pulling and drilling my rocker spindles and the wear patterns on the intake side:
rocker-spindles-t26408.html
They were scored to the point of looking like an old cylindrical phonograph record. Sorry for the lack of pictures but photobucket does not seem to like my workplace computer...you'll have to take my descriptions. Finally got around to replacing the exhaust side this weekend and was amazed to find they looked and measured every bit as good as the new ones from AN. I didn't pay close attention when I removed the intakes,( more concerned with not loosing a washer down the pushrod tube, of the position of the milled flats on the shafts. The exhausts were facing outboard as they should be. Anyone know what happens if the flats are pointing the wrong way?? Just curious at this point.
Thanks

Over oiling, swamping the intake side of the head. The oil drain hole can't cope with the volume of oil.

Mike B.

Mike B said:

Over oiling, swamping the intake side of the head. The oil drain hole can't cope with the volume of oil.

Mike B.

Click to expand...

Thanks. Symptoms of this might be oil smoke from the exhaust then?

Absolutely.

Mike B.

Anyone know what happens if the flats are pointing the wrong way??

For a start, the bores of the rockers will wear badly because of lack of bearing area. The flats in the rocker shafts are more of less at the top, where no real contact is made. If the shafts were rotated 180 degrees, the flats would be more or less at the bottom, and so far too little bearing area. The edges of the flats on the rockers shafts are going to wear quicker as well. This will lead to constant adjustment of a loose tappet. It will also in the long run [ if it could possibly do a long run ] reduce the amount of oil going to the other rockers, and hence the others will wear quicker as well.

When checking the fitting of the shafts, one thing to consider is the depth of the hole in the head compared to the length of the shaft. One of mine was able to migrate inwards and loose contact with the tags on the cover plates. I discovered this by accident one day so had to fit a spacing washer and a short compression spring to hold the shaft in contact with the cover plate.

Dereck

kerinorton said:

Anyone know what happens if the flats are pointing the wrong way??

For a start, the bores of the rockers will wear badly because of lack of bearing area. The flats in the rocker shafts are more of less at the top, where no real contact is made. If the shafts were rotated 180 degrees, the flats would be more or less at the bottom, and so far too little bearing area. The edges of the flats on the rockers shafts are going to wear quicker as well. This will lead to constant adjustment of a loose tappet. It will also in the long run [ if it could possibly do a long run ] reduce the amount of oil going to the other rockers, and hence the others will wear quicker as well.

When checking the fitting of the shafts, one thing to consider is the depth of the hole in the head compared to the length of the shaft. One of mine was able to migrate inwards and loose contact with the tags on the cover plates. I discovered this by accident one day so had to fit a spacing washer and a short compression spring to hold the shaft in contact with the cover plate.

Dereck

Click to expand...

Thanks-I don't think the flats were in the wrong position after all, I had no smoking of any kind and the valves rarely required adjusting. Your answer does bring up a question though. Does oil enter the end of the spindle via the slots at the cover plates? Never really thought about it but I guess there is no other path ?

kerinorton said:

Anyone know what happens if the flats are pointing the wrong way??
SNIP
The flats in the rocker shafts are more of less at the top, where no real contact is made. If the shafts were rotated 180 degrees, the flats would be more or less at the bottom, and so far too little bearing area.

Dereck

Click to expand...

Dereck
Do they sell different rocker shafts to you guys below the equator :roll:
The cuts at 3 and 9 oclock are where the oil comes in.
The oiling flat with hole is in line with one of them :!:

So when you install them they are not at the top or bottom = front or back

I agree with dynodave.
https://andover-norton.co.uk/en/shop-de ... n-nm25350-


The slot or "cut" needs to be horizontal to fit into the tabs of the rocker endplates.
https://andover-norton.co.uk/en/shop-de ... 5-nmt2238-
So the flat will be either 3 or 9 o'clock.
Regards,
Thomas

I did say more or less at the top. I know they are approx 45 degrees off, but that is a small issue compared to fitting them wrong. [ actually, i dont know why the bloody hell they designed them like that, as all cars I worked on in those days had holes in their rocker shafts and maybe a very small groove. Mostly it was just a hole from what I can remember, but that was 35-45 years ago . The rockers on the cars did have annular grooves in the middle of their rocker bushes. maybe Norton's method is a cheap way of doing away with that groove ]

Yes the oil goes into the shafts from the outside. That's why you have to have a good seal at those end plates as it is full oil pressure.

Who knows what we get in NZ. I know the guys in the tile making business here send out shit. Never had a problem with Norton parts so far except maybe speedo/ tacho cable differences because of different speedo/tacho's. Now I am wary about stocking spares apart from chains, oil and filters.

I do however have a spare clutch cable mounted beside the new one in use, and carry a new rear brake cable and new upper throttle cable beside my battery.
I do mostly long distance riding. Late January I did 3145 miles and this weekend might be 800 plus miles.

Dereck