16 replies to this topic

[gaspen]

Hello

 

I have the old pressed type rockers in my 850

 

1) What is the thread size of the adjusting screw / nut ?  It is not 1/4, not 5/16 UNF

 

2) On the other end the piece which press the valve is hardened in its whole "volume"  or just the working surface ?

 

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[GraemeC]

I must admit, I always thought these were 5/16" UNF

Everything on MiniSpares also indicates this:

https://www.minispar...VO.aspx|Back to

https://www.minispar...|Back to search

https://www.minispar...|Back to search

[gaspen]

I must admit, I always thought these were 5/16" UNF

Everything on MiniSpares also indicates this:

https://www.minispar...VO.aspx|Back to

https://www.minispar...|Back to search

https://www.minispar...|Back to search

 

I have both 1/4 and 5/16 nuts. 1/4 is  smaller, 5/16 is bigger than the adjusting screw.

 

12A1215 / 6K654 is the correct nut and screw for these rockers, but MS says only that "NOT UNF" 

 

https://www.minispar...ssic/6K654.aspx

 

https://www.minispar...ic/12A1215.aspx

Edited by gaspen, 04 September 2024 - 07:55 AM.

[Spider]

I'd need to check the tap I have in the draw on the diameter, but off hand, I'm pretty sure they are 9/32" BSF (yes, I bang my head against the wall every time).

[GraemeC]

Apologies - I've never run the presed type, always swapped them out for later ones!

[DeadSquare]

Question 2)

 

From an engineering perspective, it would be far too difficult to just harden the working surface of such a small item, compared to choosing a self hardening steel, heating a batch and anneal them.

Edited by DeadSquare, 04 September 2024 - 10:39 AM.

[DeadSquare]

Apologies - I've never run the presed type, always swapped them out for later ones!

The Austin 803cc A series engine had forged, not pressed rockers.

[Spider]

2) On the other end the piece which press the valve is hardened in its whole "volume"  or just the working surface ?

 

They see not through hardened, but they do have a reasonable case. They can be re-ground quite OK.

[gaspen]

Question 2)

 

From an engineering perspective, it would be far too difficult to just harden the working surface of such a small item, compared to choosing a self hardening steel, heating a batch and anneal them.

 

That was my guess also 

[gaspen]

 

2) On the other end the piece which press the valve is hardened in its whole "volume"  or just the working surface ?

 

They see not through hardened, but they do have a reasonable case. They can be re-ground quite OK.

 

 

And this is why I asked this 

[GraemeC]

Apologies - I've never run the presed type, always swapped them out for later ones!

The Austin 803cc A series engine had forged, not pressed rockers.

Lucky thing. Not sure what that has to do with my comment, or why it needed to be in bold?

[DeadSquare]

 

 

Apologies - I've never run the presed type, always swapped them out for later ones!

The Austin 803cc A series engine had forged, not pressed rockers.

Lucky thing. Not sure what that has to do with my comment, or why it needed to be in bold?

 

 

My apologies for confusing you.  I was indulging my sense of amusement.

 

I use bold (I could use a colour) to differentiate from the quote, and my tongue-in-cheek but not expressed comment inferred that you could have "swapped the rockers out for" earlier ones.

[Spider]

Sorry, going off topic here;-

 

 

 

 

 

Apologies - I've never run the presed type, always swapped them out for later ones!

The Austin 803cc A series engine had forged, not pressed rockers.

Lucky thing. Not sure what that has to do with my comment, or why it needed to be in bold?

 

 

My apologies for confusing you.  I was indulging my sense of amusement.

 

I use bold (I could use a colour) to differentiate from the quote, and my tongue-in-cheek but not expressed comment inferred that you could have "swapped the rockers out for" earlier ones.

 

 

OK, gotya on the bolding however, it's really not necessary or desirable.

 

We can see who wrote what as posts are quoted, there's a box around each of our words and the author of those parts in the top of the box.

 

You may not realise it, but it's not an accepted practice on social media to make all your posts in such a way, It comes across as though you are wanting to stamp your boots and grab that additional bit of attention over all the other posts in any thread.

The general idea of bolding, is as I have done here, to really grab one's attention to a few particular details. With this in mind, can we ask that you respectful cease from it, unless it's needed. Don't worry, we won't miss what you are saying.
 

[gazza82]

Apologies - I've never run the presed type, always swapped them out for later ones!

The Austin 803cc A series engine had forged, not pressed rockers.

Well I've asked a few A30 owners and all say pressed rockers on the 803cc ... they are pressed on the A35 948cc engines too if mine is anything to go by.

[DeadSquare]

 

 

Apologies - I've never run the presed type, always swapped them out for later ones!

The Austin 803cc A series engine had forged, not pressed rockers.

Well I've asked a few A30 owners and all say pressed rockers on the 803cc ... they are pressed on the A35 948cc engines too if mine is anything to go by.

 

I remember hanging round a garage in the mid 1950s when a mechanic was setting tappets, and being told that "They don't make things like they used to",  because after the BMC amalgamation, the rockers were "Made out of bits of bent metal", and I'm sure he showed me the difference.