A tale of two heads and one barrel. To spigot or not to spigot?

Fast Eddie said:
So, to re-cap, gpzkat shows a pic of his barrel that appears to not have any evidence of liners. He tells us he’s pretty sure it does not have liners. He takes his barrel to a professional machine shop, who tell him it has not got liners in. You, who have never seen his barrel, are saying that gpzkat and the machine shop guy are both wrong?!
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I see a future in politics!
 
bill said:
So what you are stating is that EVERY cast iron block made in the automotive industry came with liners as there is NO way they could achieve a final finish in a rough casting ? Give me a break as i have worked in the automotive machine shop and you sir need to rethink your stance. I also have tried a larger than .060 over bore on 750 Cylinders and usually the results have not been good. This has also been discussed a while back as to using liners in norton cylinders with the same foolishness. As to your atlas I would say somone did a bodge putting liners in it and THAT sir is where your troubles started. To install a liner properly it will have either a counter bore at the top or a step left at the bottom of the bore and without either one of these it WILL result in just what you encountered
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Then, how did Norton achieve the spigot sticking out of the top????
 
Your mention of the 850 barrel set my old brain in motion, when I remembered that from mid 1966 on Norton went over to non spigotted barrels.
Since I've never stripped down any norton from the 70s , I clearly forgot. So , humble apologies to everyone.
I assume Norton went over to a better casting shop who used far superior materials, since all earlier ones were spigotted.
Once again, humble apologies.
 
Bernhard said:
I assume Norton went over to a better casting shop who used far superior materials, since all earlier ones were spigotted.
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Just for clarity here, I think we have clearly established that even the earlier spigotted barrels did NOT have liners fitted by the factory when new.

Also for clarity, I’d like to point out that the presence of a spigot has NOTHING to do with the presence, or not, of a liner.

A spigot in this application (to my knowledge at least) was a design feature to assist with head gasket sealing.

Some liners do have spigots, but that’s when they are to be fitted to a barrel that needs a spigot due to the above. In this case, a spigot would also provide the same function as a step as well.

Perhaps some have confused the function of a spigot with the function of a step. A step is often built into a liner in order to help secure them and prevent them from dropping. Such a step does not need to be a huge OD and when these are required, the barrel is machine to accept the step, then (in most cases) skimmed flat again to provide a flat head gasket surface.

So in summary, my understanding of some of the topics in this thread are:

1. No Norton twin barrels were fitted with liners when new at the factory.

2. The presence of a spigot has nothing to do with the presence of a liner.

3. Liners may have spigots and they may have steps, but they are two different things serving two different functions, although a spigot would usually double as a step.

Is that a fair summary?
 
Fast Eddie said:
Just for clarity here, I think we have clearly established that even the earlier spigotted barrels did NOT have liners fitted by the factory when new.

Also for clarity, I’d like to point out that the presence of a spigot has NOTHING to do with the presence, or not, of a liner.

A spigot in this application (to my knowledge at least) was a design feature to assist with head gasket sealing.

Some liners do have spigots, but that’s when they are to be fitted to a barrel that needs a spigot due to the above. In this case, a spigot would also provide the same function as a step as well.

Perhaps some have confused the function of a spigot with the function of a step. A step is often built into a liner in order to help secure them and prevent them from dropping. Such a step does not need to be a huge OD and when these are required, the barrel is machine to accept the step, then (in most cases) skimmed flat again to provide a flat head gasket surface.

So in summary, my understanding of some of the topics in this thread are:

1. No Norton twin barrels were fitted with liners when new at the factory.

2. The presence of a spigot has nothing to do with the presence of a liner.

3. Liners may have spigots and they may have steps, but they are two different things serving two different functions, although a spigot would usually double as a step.

Is that a fair summary?
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Yep
 
The main thing I wondered about is if the spigots are removed, top side decked etc, that it'll work with the nice later cylinder head I have. I am confident it will from 'book learning', but reality can bite. I would like to run my stock concave pistons if possible. One cylinder looks fine, but the other is rusty.

I would actually prefer a liner on the bad cylinder to return it to the original bore if it can be properly done. That's a controversial subject too, as I've read. I'm running the cost/benefit analysis in my mind.

I think with a proper liner installation, with either a ridge left at the bottom to stop any movement or some other way at the top or bottom to ensure it stays put, it would be OK, but I don't know all the facts at this point. I'll call the shop soon. The guy I talked to said another fellow has lots of experience on Nortons, FWIW, but he's not been well. I am not in a hurry and learned long ago to not bug people too much, let them think about it (hopefully).

I have lots of other fishes to put in the pan for now, and I'll update when I get more info.
 
As per previous postings you with a re-sleeve run the risk of weakening the barrel flange, surely the cost of a rebore and new pistons would be similar to a re-sleeve, and as most of the Norton's exports went to the USA you would have a better chance of finding a new old stock set of over size pistons in the US than anywhere else in the World?
 
I must say all the debate over sleeving confused me as to the answer to the original spigot question. To summarize my understanding of the answer of the original question, the spigot may be cut off a spigoted barrel to form a non-spigoted barrel (assuming no sleeving) as there is no difference between the early atlas with spigot and later atlas without spigot except for the spigot. If I am incorrect please clarify. Thanks in advance.
 
ilikevelos said:
I must say all the debate over sleeving confused me as to the answer to the original spigot question. To summarize my understanding of the answer of the original question, the spigot may be cut off a spigoted barrel to form a non-spigoted barrel (assuming no sleeving) as there is no difference between the early atlas with spigot and later atlas without spigot except for the spigot. If I am incorrect please clarify. Thanks in advance.
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You match the spigot to the head you have. So flat head means no spigot, head with recess then retain the spigot or fit the parts Norton made to fill the recess in the head if your barrel is flat.

Example of ring

www.rgmnorton.co.uk

ALLOY RECESS RING FOR CONVERTING SPIGOTED CYLINDER HEAD TO NON SPIGOTED

ALLOY RECESS RING FOR CONVERTING SPIGOTED CYLINDER HEAD TO NON SPIGOTED OUTSIDE DIAMETER: 3 1/8" (79.4MM)INSIDE DIAMETER: 2.924" (74.25MM) DEPTH:
www.rgmnorton.co.uk
 
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ilikevelos said:
I must say all the debate over sleeving confused me as to the answer to the original spigot question. To summarize my understanding of the answer of the original question, the spigot may be cut off a spigoted barrel to form a non-spigoted barrel (assuming no sleeving) as there is no difference between the early atlas with spigot and later atlas without spigot except for the spigot. If I am incorrect please clarify. Thanks in advance.
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Yeah that's right, I have two heads but the much better one which needs no repair is non-spigoted. I want to shave the spigots off my cylinder to match it.

As for using a sleeve, stay away is the consensus.
 
gpzkat said:
Yeah that's right, I have two heads but the much better one which needs no repair is non-spigoted. I want to shave the spigots off my cylinder to match it.

As for using a sleeve, stay away is the consensus.
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Only use a sleeve if it's absolutely necessary
 
gpzkat said:
The main thing I wondered about is if the spigots are removed, top side decked etc, that it'll work with the nice later cylinder head I have. I am confident it will from 'book learning', but reality can bite. I would like to run my stock concave pistons if possible. One cylinder looks fine, but the other is rusty.

I would actually prefer a liner on the bad cylinder to return it to the original bore if it can be properly done. That's a controversial subject too, as I've read. I'm running the cost/benefit analysis in my mind.

I think with a proper liner installation, with either a ridge left at the bottom to stop any movement or some other way at the top or bottom to ensure it stays put, it would be OK, but I don't know all the facts at this point. I'll call the shop soon. The guy I talked to said another fellow has lots of experience on Nortons, FWIW, but he's not been well. I am not in a hurry and learned long ago to not bug people too much, let them think about it (hopefully).

I have lots of other fishes to put in the pan for now, and I'll update when I get more info.
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Just how rusty is the bore?
 
ilikevelos said:
I must say all the debate over sleeving confused me as to the answer to the original spigot question. To summarize my understanding of the answer of the original question, the spigot may be cut off a spigoted barrel to form a non-spigoted barrel (assuming no sleeving) as there is no difference between the early atlas with spigot and later atlas without spigot except for the spigot. If I am incorrect please clarify. Thanks in advance.
Click to expand...
Unfortunately you get idiots on here that claim they know everything and it can lead to confusion
 
baz said:
Just how rusty is the bore?
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Sorta hard to describe, and I don't have a good pic anymore, lost it I guess. I de-rusted it chemically then ran a flex hone, it cleaned up quite a bit as usual and one is usable, it didn't etch deep and no pits. But the bad one has an area about the size of a small mouse that I don't think is fixable without surgery. Will see though, maybe they have ways to recover it.
 
gpzkat said:
Sorta hard to describe, and I don't have a good pic anymore, lost it I guess. I de-rusted it chemically then ran a flex hone, it cleaned up quite a bit as usual and one is usable, it didn't etch deep and no pits. But the bad one has an area about the size of a small mouse that I don't think is fixable without surgery. Will see though, maybe they have ways to recover it.
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Ok I see what you mean
You'll need to get it checked/ measured by someone competent
I know some people like a bit of rust because once removed the pitting can retain some oil (so it's said)
But I've no experience of this
 
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