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ES2 Rocker arm woes

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My 1951 ES2 is currently in pieces as I sort our various "issues"

My mechanic friend has advised me that I need new valves and valve seats on the exhaust side and fortunately the NOC has stock

He also pointed out that the intake side Rocker has extremely worn pads where it contacts the push rod and valve

apparently it has been improperly adjusted at some time in the past 66 years...surprise-surprise eh

the Rocker arm ball end fitting is worn to a bit of a point

The pad at the valve end is deeply indented...probably well below the case-hardened surface so simply dressing out the damage seems like a short term solution. Replacement of the part is ideal

I can find the rocker arms on line but these don't have the pads and are not in need of replacement.

the 1950 Norton parts list shows Rocker arm ball end, part number C3/104 and the Rocker arm Pad part number C3/105

Does anybody know of a source: new or used of these parts ?

Does anybody have a rocker arm with acceptable pad and ball that I could buy to scavenge the parts?

Alternatively do I need to find somebody who can build up the metal then do the appropriate hardening process?

any advice would be greatly appreciated

Grant MacNeill, Toronto

Attachments IMG_1095.JPG IMG_1096.JPG technical1-
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As far as I know the pads are not case hardened (not sure about the ball ends). I gave my head to Mike Pemberton and he reground the pads for me. You have to be careful that when you recut the valve seat for the new valve that it doesn't result in the valve sitting too deep in the head, if the valve extends more than a fixed length above the guide (sorry can't remember what it was!) the valve springs are likely to touch the inside edge of the rocker box. There's not much room for wear. If it does exceed the limit then you may need to have a valve seat inserted into the head. Have a look in the rocker box they might have already been touching. You can always give Mike a call, he'll help you out with the info, or send it to him, although the postage might be a bit steep!

dan

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The followers probably are through the hardening but could be built up by stellite welding and refaced.

My first port of call for valves would be G&S Valves. They are plasma coated and superbly finished - much higher quality than anything available at the time.

I would post a link but this message board doesn't allow copy /paste in Firefox (aargh !)

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Richard I am 99% sure that the pads are not case hardened and can be ground back to shape, and if needed Mike recommends that you should use an austenitic steel exhaust valve (non magnetic) to cope with the heat.

Mike can give you all the info you need for the price of a phone call!

Dan

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Previously Dan Field wrote:

As far as I know the pads are not case hardened (not sure about the ball ends). I gave my head to Mike Pemberton and he reground the pads for me. You have to be careful that when you recut the valve seat for the new valve that it doesn't result in the valve sitting too deep in the head, if the valve extends more than a fixed length above the guide (sorry can't remember what it was!) the valve springs are likely to touch the inside edge of the rocker box. There's not much room for wear. If it does exceed the limit then you may need to have a valve seat inserted into the head. Have a look in the rocker box they might have already been touching. You can always give Mike a call, he'll help you out with the info, or send it to him, although the postage might be a bit steep!

dan

Thanks Dan. I've already got Mike Pembertons DVD on the engine and gearbox rebuiild. Very helpful but he does not mention what do do if these parts are worn. I should drop him a line

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Previously Andy Marks wrote:

Hi Grant

Where have you seen the rocker arms for sale?

Andy

Hi Andy. there is an inlet rocker arm on page six of the NOC Engine parts for sale page. last page of that section. I forget now where I've seen others as it has only been in passing as it is never a part I've previously had to look for. I see that Mike Pemberton sells a set on his site

Mine are fine... it is just pad at the end that I've got wear problems. I may have found a company locally that will build up metal and harden for me. That said hoping to find them somwhere. Grant

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Previously richard_payne wrote:

The followers probably are through the hardening but could be built up by stellite welding and refaced.

My first port of call for valves would be G&S Valves. They are plasma coated and superbly finished - much higher quality than anything available at the time.

I would post a link but this message board doesn't allow copy /paste in Firefox (aargh !)

Thanks Richard. I've already emailed G&S for a price with shipping. They certainly seem to make lovely product.

Grant in Toronto

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Previously Dan Field wrote:

Richard I am 99% sure that the pads are not case hardened and can be ground back to shape, and if needed Mike recommends that you should use an austenitic steel exhaust valve (non magnetic) to cope with the heat.

Mike can give you all the info you need for the price of a phone call!

Dan

Thanks Dan, I've found valves at the NOC store, Andover Norton, Norvil etc. None say if they are Austenitic steel or not. I was about to order and now I'm pausing to do a little more research. This is only an ES2 but that said, I do a lot of highway miles and and want maximum life. I will speak with Dan.

It does appear that my rocker pads can be preserved. I would like to replace the Ball End Nipple at the other end as it feels like it has worn slightly oblong but I may have to make do.

Grant

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Previously grant_macneill wrote:

Previously Dan Field wrote:

Richard I am 99% sure that the pads are not case hardened and can be ground back to shape, and if needed Mike recommends that you should use an austenitic steel exhaust valve (non magnetic) to cope with the heat.

Mike can give you all the info you need for the price of a phone call!

Dan

Thanks Dan, I've found valves at the NOC store, Andover Norton, Norvil etc. None say if they are Austenitic steel or not. I was about to order and now I'm pausing to do a little more research. This is only an ES2 but that said, I do a lot of highway miles and and want maximum life. I will speak with Dan.

It does appear that my rocker pads can be preserved. I would like to replace the Ball End Nipple at the other end as it feels like it has worn slightly oblong but I may have to make do.

Grant

Further progress: Spoke with Mike P by email and he was very informative: just grind and resurface the pads and he made suggestions about appropriate valves and guides from RGM Norton so I am much relieved.

thanks for the input.

Grant

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G&S can supply you with a stainless exhaust valve (I bought two from them, currently in use) Just make sure you have a valve guide to suit.

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RE: my worn rocker arm pads ( wear from valve stem contact)

Problem Solved ( at least one of them is )

Valve Train Industries here in Ontario did a lovely job of resurfacing my rockers. $32 for both which seems a bargain to me.

thanks for the input.

See the photos attached of the lovely workmanship.

Grant MacNeill, Toronto

Note: Mike Pemberton tells me that my deeply pocketed valves changed the contact angle at the valve stem-to-rocker arm contact angle which speeds the wear. He is a very helpful and informative guy.

Attachments img_1182-jpg

Norton Owners Club Website by 2Toucans