Cam bush ream (2017)

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jug

jug

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OK , think I got the cam play sorted. (See previous post "Camshaft lateral movement??" )
Will replace the bushes with shouldered 850 type.
Where can I purchase a Norton cam bush reaming tool. (will be cheaper than having to pay for someone else to do the job) And can anyone give me a part # for the tool.
Plenty of Triumph ones available but cant find one for a Norton.
jug
 
I guess any expanding reamer that covers the size will do it though you will need to keep it straight and lined up with the blind bush in the drive side case.
 
The only proper way to ream new camshaft bushes is line reaming both bushes together in situ. This means you need a special reaming tool because of the blind bush in the drive side crankcase so ‘any expanding reamer that covers the size’ is definitely not good enough. Consider yourself lucky to find a Norton workshop that has that special reaming tool to do the job right for you :!:
 
not a shade tree job, search in your area for line reaming/boring services, usually a specialty machine shop will be set up for this, though if they lack bike experience will likely turn you away
 
Here's one way to do it with an adjustable reamer. You have to make a sleeve for the drive side of the reamer so the bushings are aligned (alum sleeve in photo on left side). The normal driving side of the reamer is buried in the left side case so you have to turn the reamer with a wrench in the middle or from the opposite end. Much easier to just make a washer to take up the lateral play.

Cam bush ream (2017)
 
Thanks Jim, was looking at leaving the drive side in situ and just replacing the timing side only with the later bush, either 1 x 06-3020 or 2 x 06-5428. Was just a little concerned about using the scrolled bushes with scrolled cam. If I were to leave the factory bushes in, what materiel should the spacer be made of.
jug
 
jseng1 said:
Here's one way to do it with an adjustable reamer. You have to make a sleeve for the drive side of the reamer so the bushings are aligned (alum sleeve in photo on left side). The normal driving side of the reamer is buried in the left side case so you have to turn the reamer with a wrench in the middle or from the opposite end.
Cam bush ream (2017)
Click to expand...

Nice way to line ream the timing side bush but how do you line ream the drive side bush :?:
 
Just saw that I payed Holland Norton Works 50€ to replace and ream both cam bushes.
Dan
 
Indeed you will need a custom reaming tool (see picture below) to properly line ream both Norton cam bushes in situ.

Dan you got your camshaft bushes replaced and line reamed more than 3 years ago. Currently the price for replacing and line reaming camshaft bushes (excluding bronze bushes) is EUR 80,00

Also I recommend to use the one piece timing side bush (AN06.3020) instead of 2 short MK3 type bushes (AN06.5428) as these tend to come loose due to their shorter press fit.

Good luck,

Constant Trossèl
http://www.hollandnortonworks.eu

Cam bush ream (2017)
 
Jug
Make a steel washer. Drill rod if possible - hard but not brittle.

Nortonspeed
Below is a 7/8" reamer with a plastic sleeve. The sleeve locates in the opposite bushing that you are reaming. You may have to cut the reamer to length and then make a longer sleeve. You have to work out your own way to turn the reamer -anything from a vice grips to flats on the shank that you can grab with a wrench or a slot or other type shape or fitting on the end. Holland Norton works looks like they made up or bought a custom/specific reamer. There are different ways and tools to achieve this. Take your pick.

Cam bush ream (2017)
 
Not recommending this as a standard procedure, but just relaying my experience. Some years back, I had occasion to correct the fit of the drive side cam bushing after welding reinforcements on the cases. The cam was a very tight fit in the bushing, rubbing in two areas that indicated it was no longer concentric with the shaft. I marked the interfering areas by applying blue Dyken and then rotating the cam. The areas of missing Dykem clearly showed where the interference was. I scraped those areas with a triangular bearing scraper until the cam rotated freely. This was on a race engine that I subsequently ran for many years with no problems.

Clearly, precision line reaming is a more desirable approach. But the old-school techniques of scraping bearings are still sometimes useful.

Ken
 
Holland Norton Works said:
Indeed you will need a custom reaming tool (see picture below) to properly line ream both Norton cam bushes in

Also I recommend to use the one piece timing side bush (AN06.3020) instead of 2 short MK3 type bushes (AN06.5428) as these tend to come loose due to their shorter press fit.

Good luck,

Constant Trossèl

+1
When I rebuilt my engine I had the inner timing bush (MKIII) fall out while I was staking the bung plugs in place. It was obvious that it had spun and was loose. I used a one piece non-scrolled bush and was lucky enough to have the proper size hand reamer in my tool box. When done I blued the cam and tested fitted like Ken did. Fortunately everything worked out good. The only thing I wasn’t crazy about was I had to use the earlier tabbed washer (with tab removed) behind the cam gear. In retrospect I wonder if cutting the flange off of a top hat bush would have worked as a spacer. The idea of using the one piece bush came from one of our Access Norton guru’s.
Pete
Click to expand...
 
Here's my version for the drive side again with refreshed photo.

Below is a 7/8" reamer with a plastic sleeve. The sleeve locates in the timing side bushing. Turn the reamer with flats on the reamer and a wrench or a slot or other type shape or fitting on the end.


Cam bush ream (2017)
 
lcrken - from 2017 post #12
Old school indeed, we did the same scraping technique in the 70,s to final fit white metal refrigeration compressor bearings which we also poured and machined.
From memory, one of the old English tradesmen said his wife did the same hand scraping operations on certain Rolls Royce Merlin(?) engine assemblies during WW2.
Can,t recall what they were but it got my attention and I,ve done many hand machining operations since with great success and very little cost using the most basic tools available at the time.
A component that fits and works perfectly doesn,t really care if it,s been done by hand or machine.

I did a similar mod as you on my 2010 Commando rebuild but used an old Bosch variable speed pistol grip drill and small flapper type sanding wheel on a tight lefthand cam bush.
Just did a little at a time, checking progress with both cases together until the cam was a perfect smooth fit, cleaned it up, then hand ground a thrust washer on the right side to give 0.006" clearance.
Didn,t take long at all and still a perfect fit in 2016 when a new Webcam 312 went straight in.
 
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I was done struggling decades ago and as you learned more it became not only easier to do but even more enjoyable, no cussing, no sweating, no frustration which was all self induced not having the tool for the job.

Heat the case in the oven.

Put the bush in the freezer the day before after you have chamfered the oil hole on the OD, that way unlike the factory it will not cut a furrow in the bore of the engine case.

Line the oil holes up bush to case and in it goes with no drama, the mandrel for the bush has a hole that takes a spigot on the drift, it engages in the T/S bore so no chance of the bush being driven in cocked.
It also avoids mushrooming the drive face of the bush.
My NOS camshaft went in nicely.

Sure it takes some time to machine parts but well worth it when the job goes easy.
I might add I am a Boilermaker/Welder not a mechanic or machinist. :D

Cam bush ream (2017)


Cam bush ream (2017)
 
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Constantly puzzled by the posts on this and other forums.
Since day one I have never had to ream a new cam bush.
Helps if you measure them before installation to see if they are the right size, or are bogus junk repops.
 
Well mine were from AN and the lefthand bush needed relieving after fitting, you can,t speak for others you,ve never met, who have had to do this just because it,s never happened in your experience.
Alot of very knowledgeable people around on this and other forums, they can,t all be wrong.
 
I had to take some off the face of the timing side bush on a piece of engineers glass to get end float. The drive side bush was a bit stiff, used Brasso and ran cam with drill. Now fine.
 
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