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38 Norton Colonial

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hi there.

So since I finished my 38 model 18 I fancied a full restoration this time So was very lucky to stumble across this one and being literally just down the road from me! You never know what's lurking in garden shed.

I believe it to be a model 18 Colonial version Due to the tin Work being different to mine.

I understand this was last on the road in 1978 and has been languishing in a shed ever since And I have a few questions.

I'm not sure if the engine is the original one identical but not the original and I have all the engine numbers and frame numbers as below.

engine number A3 5255 Q.  What does the Q mean? And what can be learnt by this engine number?

Frame number 86855. What do we know about this?  It does have a sidecar bracket on the top of the frame, but this looks unused.

Could someone tell me what type of gearbox this is as clearly not a Dolls head?

Hopefully the pictures will help, but any information would be so gratefully received.
 

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1938 frame with 46 model 18 engine, but only 4 digit engine number (normally 350 designation)?
Maybe it was originally a 350 and someone "retained" the number for the 500 motor? Don't know about the Q in this scenario.

I though "Colonials" were higher ground clearance and a little less dressed for less maintained roads.

Great looking machine, a bit to go but nothing major missing, do you have the tail piece of the rear mudguard? Is it the wrong front wheel?  
 

Hi Jonathan.

Thanks for the info. It does say 79 x 100 on the crank which dictates its a 500. 

I've yet to get it home, but looking forward to getting to know this one:))

The only thing I can see is missing is the dynamo and the speedo,, speed drive The speedo drive is on the rear of the front drum rather than being on the front, 

Yes, I've got the rear mudguards, Why are these mudguards much larger?

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The engine is definitely a 500cc. A3 signifies a 1946 Model 18. When production recommenced in 1946, the numbering system started with a letter (A for 1946) and a number for the model. The sequential numbers started at 1001.
Engine number A3 5255Q would have been despatched August to early September 1946.
The letter Q indicates that the cams have quietening ramps.
The frame number indicates a prewar frame from Dec 1937 to early January 1938.
The gearbox is correct for 1946 with the push-in circular disc.
A quick look at the photos show prewar girder forks with a post war front brake. By 1946 the brake was mounted on the right hand side of the girders. The forks are correct for most prewar models although several models had right hand mounted front brakes in 1937.
Handlebars are missing the tangs to mount onto the top of the forks together with the speedo bracket.
I'd also be checking the integrity of the frame repair near the rear of the gearbox.
Message me if you want any more information.

Thank you so much, Ian, Extremely valuable information, which I have logged.

When I bought it, he did say it was not the original engine but overall condition confirmed as untouched since 78 to 80, That's good so I have a great basis to work from.

Also as points of reference, I do have a near concourse 38 Model 18 pictured below I have been using since Midsummer extremely reliably.

I know I'm gonna have to find some gearbox mounting plates so I'm assuming the pre-war frame and the postwar frames were the same being a tombstone gearbox?

my mint bike does have the front brake on the left-hand side also put on this one the speedo drive is on the rear part not on the front so I may actually put that back as a pre-war.

I do have the early version of the V5, which tells me it was first registered in February 38 Showing the correct frame number but showing a different engine number, I'm thinking this would be near impossible to find the correct engine for it unless I take a trip to its known previous owners on a win whim.

I will take it right back to the frame and actually send these to an expert for the frame to be checked and repaired professionally buy sleeving the repair.

thank you for your very kind offer of assistants!!

 

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Needs a good check out.  A common failure point on open cradle frame. If it's just butt welded  I'd sleeve it or cut it out the tube and replace.

I missed out that 45-47 were also four digit numbers so as Ian says it falls in to 46.
The "3" denotes it as a model 18, I didn't realise the "Q" Quitening ramps identification started so early. I thought it a Dominator term.  Learn every day.
The mudguards we're often like this prewar,  don't know too much about Tinware changes.  Gearbox is a cleaned up version of a dolls head, commonly referred to as a tombstone.

A bit to go at but rubber wear, handlebar clamps and dynamo are generally available.  What's your intention with it?  Whatever you do I would get it into a fit state to run up and see what you have got. The ravages of time are far kinder than the ravages of some restorers, you may be lucky.

Apply for a dating cert, you have two sources of info being the frame for the bulk of the machine and then the drive train.  The records may give you some insight into its origins, and engine donor.

;-)
 

Thank you, Jonathan.

Again, very much appreciated. Please keep the good stuff coming.:))

so we've established it a 46 engine as I know the two previous owners in terms of information I'm going to try and see if they hold onto the original never know:))

when I saw the bike yesterday it does come with a lot of new old stock components due to fitted like a complete clutch and two brand-new old stock chain cases which is so valuable to me.

obviously, it was fitted with a speedometer at sometime, but I can see the mounting Tangs underneath the Bakelite tensioner.

I think I'm gonna do a full restoration rather than keeping it in its current form but get it mechanically ready. This is still yet to be determined, but I'm not sure about running the engine in its current state or attempting to. 

Need to investigate inside First by Popping the head off and see what where there is and the state of the bore.

It does turn easily, which is great, but I'm thinking maybe those big and little ends need replacing, 

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At this stage ignore the electricity. The dynamo might be a 3 brush, these were horrible things at the best of times-needs converting to two brush, modern regulator-done. This sort of machine can be completely rebuilt as far as mechanics, paint etc needs a decent magneto etc perhaps investigate purchase-even fit a dynamo. But the last thing you do/worry about is the wiring. But do locate the battery space and what is available as far as a battery.

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Thanks Alan

I will replace all the wiring with the correct type as looks so much better:)) And really enjoy doing that .

The dynamo I think is Lucas MO L series twin brush.

Just need to locate the correct gearbox plates and footrest etc As well as a new set of engine bolts , Luckily enough, the chap had a brand-new clutch complete, I'm sure the list will go on:))

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You can't replace the wiring with the 'correct type' as it doesn't exist. NOS wiring from 1938 will be well past it usability.

In reply to by alan_osborn

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Hi Alan
 

i will be using cotton fabric braided cable which is an authentic replacement cable for it.

I will have to dig out the colour charts again:)))

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The 1946 engine was of the pre-war 1938 type, although I believe that there were some small changes to the rocker box castings. To all intents and purposes, unless it's being fitted in the more compact WD16H frame, they are identical.

The horizontal rear saddle spring lugs indicate that this is not a WD frame.

In pre-war terms, apart from OHC, only the ES2 had a full cradle frame. All post-war roadster frames had a full cradle and the ES2's "Extra Specification" became plunger rear suspension.

 

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Thanks, Richard.

All good stuff, thank you, Actually, I understood the ES2 to stand for enclosed spring 18 is enclosed as well, so I didn't actually know the difference between the 18 and the Es2,

What are the differences apart from the cradle frame?

Even back in the 1950s, it had been forgotten just what "ES" stood for, no-one who worked at the factory knew ! Why was there never an "ES1" ?

I tend to favour the "Extra Specification" theory as it has the feel of the advertising jargon of the time and they were always a deluxe version of the Model 18.

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As Richard says the ES2 had the full cradle frame, yours is open therefore Model18.  Never sure of the ES meaning Extra Sport, Extra Special, Extra Speed... Always seen as the sports version of the pushrod Nortons.
j

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Very excited this morning and got straight to work, but I thought I would do a quick picture of the two together, 

well, I tried, but it wouldn't download:))

I took the gearbox and engine out and all the original wiring, There is a little bit of end float in the crank So will split the engine and see what's going on.

The mud guards have been welded so much and really are falling to pieces so I will get some made, I know there is a UK manufacturer and supplier and anybody let me know who it is?

also the frame needs repairing so may as well have it professionally prepared and painted. Also who is the best person to do this as I think it needs sleeving and work to a very high standard?

 That's a lovely looking bike.
Out of interest, you mention having new mudguards made, what do you do with the old ones in this situation?

Actually I think you chaps are right, It's only right that I restore the original ones they just don't look quite as nice being so big and I'm wondering if this was an optional extra?

The best bloke that I know who repaired my Commando frame to my exact requirements was Ian Bain, a restorer of repute with a CV full of excellence and satisfied customers to verify it.
His workshop is near me up here in Wdnes, Cheshire.
 

In reply to by ian_richtsteig

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Not yet, but if anybody knows them, it would be great if you could give me the number and details.

I've been repairing the oil pump:)))

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...will recover those mudguards. Cracks are manageable loses can be reinstated.  Far better to recover the originals, and probably cheaper.  Straight frame tubes can be replaced fairly easily tapered one also, but getting swaged tube is sometime a little difficult. Is there an issue on the lower offside gearbox tube?

Get your machine together as complete as you can then group the tasks. Motor gearbox is straightforward, they can be done in parallel to the chassis and tin wear.

Any luck with locating the original motor?
j

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Hi there.  Not yet, but there are only three owners and if I have to get in the car and knock on the door, then it's worth it I think.

I do have a few other questions, I started to strip the engine which it absolutely needed as the piston rings were broken, but the bore are actually okay And will just need honing out.

The piston says 20 thou oversized Which is good news and I will replace this as it has started to pick up.

the oil drive worm gear is incredibly tight.  Can one of you chaps tell me which thread just to check I'm guessing left to undo before I put an real pressure on?

the oil pump is smooth notchy, not how I think it should be I don't believe can someone just confirm this as I'm thinking it should be typically smooth all the way round?

updated
I took it apart good clean and polished the shaft up and now it pumps like a trooper:)))

I will get to the head later, but I noticed the valve stem seal has broken.

The 1938 engine had wider cam gear wheels than the earlier pattern. I think you're seeing a machined clearance rather than witness marks. The photo below shows a 1946 engine on the right with a 1936 type on the left.

I think it would take a lot more wear than is apparent there on the thrust face of the bushes to allow contact with the timing chest wall.

Thank you, Richard. So much very helpful..

Makes total sense because the inside of the cam wheels are hardly really marked and certainly don't have the amount of scratching or wear on the cam wheels compared to the casing!

I'm taking all the alloy components up to be vapour blasted and cleaned up so just organising a shopping list of what I need:)))

0.20 oversized piston with rings
Big and little ends.
crankshaft bearings x 3
exhaust camshaft. as has a little bit a wear on the lobe.
engine casing bolts throughout.
Stem seals
Gaskets and oh  the list goes on:))))
 

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Easily checked by refitting inlet cam and timing cover and then checking for the amount of end float.  You can then shim to reduce the end float by fitting shims behind the cam wheel.

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Thanks for that, check in situ, I'm gonna do a full engine rebuild so it needs to be perfect.

In terms of afloat, there was at least 3 mm of float on the crank and Maybe more on the con rod By tilting it left and right.

I'm thinking racing Norton for all the engine components that I may need?

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Hi all

can I ask quite a simple question? Should there be two head gaskets?

The reason I ask is because there is a copper ring that sits on top of the bore/ sleeve to the head.

There was no large head gasket that came off and no indication of one being on there.

cheers

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Hi Matthew,

   Sorry to be the bearer of bad news, but looking at your latest photos, you will not be able to use your cylinder bore as it is. The ridge around top is the actual original bore size, the lip is how much the bore has been worn away and I don't think I have seen one with this much wear before.You may get away with a plus 40 rebore, but don't be surprised if you have to go to plus 60 to get it to clean up. This must have had excessive piston slap which is probably why the rings were broken, you will need to check the rebore situation before you get a new piston.
   The head joint should not have a gasket or sealing ring and you need to grind the joints together using valve grinding paste, coarse on the outer face and fine on the spigot so this gives a very slight gap on the main contact area which will ensure the spigot seals first. Most gasket sealants can be used on both joint faces.
   

   

Hi Richard, thank you for your very valuable advice.

So I have a couple of questions just to clarify I'm airing on the side of what you say totally.

I've used the honing stones to clean up just to give me a bit more visual what's going on.

I have a new 20, thou piston Which is possibly gonna be not sufficient now.
I've attached some pictures after the honing which did take a bit to be fair and does seem to be marginally oval looking at the "post" honing marks

Can I just ask a bit more about the head gasket? Are you saying there should be no head gasket and the mating surfaces should be ground to match?

 

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Hi Matthew,

   The wear on your barrel is unusual with excessive wear on the sides rather than the front and back. This is probably due to the 3mm end float of the crankshaft forcing the piston from side to side. The correct end float should be .005 to .010 inch with the con-rod central in the crankcase mouth. You will need to find the reason there is so much end-float on this engine as you might have the wrong main bearings or drive-side centre spacer.
   With the piston in the barrel and level at the top, you should be able slide a .006 inch feeler gauge between the bottom front (or rear) of the piston skirt and the barrel. If the gap is more than .014 inch then the bore is beyond useable tolerance, Even so, with the top wear you will need a rebore anyway. 
   Regarding the head gasket, these were only fitted to make factory production quicker. Grinding the head joint is the correct process, and to support this, no Manx or International engine had a head gasket. Make sure all the contact surface has a matt grey surface to indicate a perfect seal.

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Richard cannot thank you enough,

I've taken it to the machine shop and they are going to test bore At 40 thou To see if it cleans up,

I will be putting a new main bearing in which is yet to arrive and split the crankshaft.  I I did notice there is a lot of end float on the crankshaft so hopefully I will be dealing with that and I have the associated shims

I haven't done this before, however understand what's required.

Let's see what the machine shop comes back with!

Many thanks, Richard

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Matthew,
In your photo IMG_7136.jpeg there is a useful looking thread gauge (red), please can you tell me the maker so that I can find one.
A good supplier of piston rings is Cox & Turner and they are very knowledgable about all things that need machining in an engine, cylinder
barrels and heads, see https://www.coxandturner.co.uk/
for details.  They had +0.060 rings on the shelf when I recently needed some for my Model 18.

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hi there 

I bought it off eBay a couple of years ago.

Just type this in and it should come up.

Nut and Bolt Thread Checker 28 Thread Identifier Gauge Inch and Metric

Thanks for the useful advice reference piston rings. I've actually ordered most things I need from RGM Norton which seem to be really good with all components needed!

 



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