Heart Transplant

motorson

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But, Swoosh, by doing the best job you will be releasing another great Commando engine to the world! That in itself is a worthy cause. You definitely have a combat crank case with the oil intake way at the front. The modification on that is an important one if an engine is to be run hard. (What Norton does not get run hard from time to time?) I would build it as well as I could reasonably afford even if it was just to keep it as a spare engine. (too bad about your agreement with the original owner.) In my view, every once in a while an entire Commando will fall out of my extra parts. :)
 
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I agree with Fast Eddie,
Don't cheap out. New crank bolts, Superblends and new shells after checking the crank journals if they look good. Most of these engines of that 200000 series were not using oil filters back then and I think it was introduced around 1973 onward as standard. (but don't quote me on this) If you are going to do this all over again, then a 17mm drill rod 1 ft. long and two hard wood pcs from the hardware store is all I use.
I would do the dynodave oil pickup mod on the cases while your in there and you should have a good strong engine. What cam do you have in there?
Keep on keep'n on.
Cheers,
Thomas
 
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But, Swoosh, by doing the best job you will be releasing another great Commando engine to the world! That in itself is a worthy cause. You definitely have a combat crank case with the oil intake way at the front. The modification on that is an important one if an engine is to be run hard. (What Norton does not get run hard from time to time?) I would build it as well as I could reasonably afford even if it was just to keep it as a spare engine. (too bad about your agreement with the original owner.) In my view, every once in a while an entire Commando will fall out of my extra parts. :)


I don’t think the cases in 1972 were any different at all between the Combat and non-Combat. It was the cam and shaved head and bigger carbs but that was about it.

Am I wrong?
 
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Shorter pushrods, bigger ports on the head. But that doesn't necessarily mean that was a good thing. I think Dynodave tested his combat on a dyno which put out 48 hp at the rear wheel with the smaller ports. Any markings on your cam?
Cheers,
Thomas
 
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Any markings on your cam?
Cheers,
Thomas

46421782751_b0de244d57_h.jpg


Say... what's this?

44606558400_c12bb877ba_h.jpg


So this engine never was upgraded to Superblends. So I can either downgrade the cam or upgrade the bearings or just stay off the top of the rev range...
 
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L.A.B.

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What would be the difference?

6/MRJA30 is the 'Superblend' bearing.
MRJA30 isn't.

https://www.nortonownersclub.org/su...mando/commando-main-bearings-service-releases

"We are introducing a new roller main bearing arrangement in production almost immediately. The fitting of this bearing arrangement reduces overall width between the main bearings and increases timing side main bearing journal diameter.

For service purposes we shall in future supply only the crankshaft of the latest size, Part No. 063106. The main bearings, Part No. 063114, must be used in conjunction. The new bearings are 2 dot single lip roller bearings and should be assembled with the lip into the crankcase in both cases.
Main bearing Part No. 063114 is of the Ransomes type (R&M) MRJ A30.

October 1971"
__________________________________



"In order to extend main bearing life, a change of roller main bearing specification has now been authorized and fitted on production engines from Engine No. 211891. The new roller bearing is designated 'Superblend' with an increased load carrying capacity and is supplied under Part No. 063906 (manufacturers part number R&M 6/MRJA30).

August 1972"
_________________________________

"Only use bearings with one of the following numbers:- NJ306E (E is very important, NJ306 is weaker) or 6 MRJA30. The 6 may be hand engraved on the bearing."

 
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Thanks L.A.B. I never knew that there was a change of size, I am in the process of building an Atlas and already have the bearing, better check. Chuck.
 
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sd quote "So this engine never was upgraded to Superblends. So I can either downgrade the cam or upgrade the bearings or just stay off the top of the rev range..."
swooshdave, give us a picture of the head showing the gasket surface area. I want to see it there is any material skimmed off the head aka "combat-ted".

Superblends would be the cheaper option $74.80 each via Old Brits. a new cam will be much more. Is all the lobes as good as the picture shows? Based on the head if it is not skimmed, You could up the compression to close to combat by eliminating the base gasket (use 518 loctite) and using a thin head gasket system. I didn't see a C stamp on the head.
This will make the cam which you have work, as this cam needs compression. Only check the valve coil bind when assembly. That engine should pull like a train and give you lots of power and grins.
Cheers,
Thomas
 
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[QUOTE="swooshdave,


Only managed to break TWO of @Mike T's tools... :eek:


31473783487_eca39d728e_h.jpg


The second tool to fail was the pinion puller. Fortunately it still did the job with only two arms. Does anyone have a spare one laying around they want to sell? :oops:



The good news is that it should be ready to split, what else could possibly go wrong??? o_O[/QUOTE]



I could only imagine the words out of your mouth when that happened!:mad:
It is too bad that we can't buy just more jaws for the puller. I think we need to talk to AN about that.
bummer just the same.:oops: You really need to make the outer ring nut as snug as can be with no misalignment behind the gear.
 
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I could only imagine the words out of your mouth when that happened!:mad:
It is too bad that we can't buy just more jaws for the puller. I think we need to talk to AN about that.
bummer just the same.:oops: You really need to make the outer ring nut as snug as can be with no misalignment behind the gear.

Luckily @Mike T was actually helping me at the time so we could share the profanity.

There are many brands of pullers out there. And since they are shared with Triumphs they are readily available and not horribly expensive.
 
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32554713078_faced64558_h.jpg


As for the connecting rod holder I got some red oak and will cut the appropriate holes in it. Provided I run the grain the right way it's shouldn't ever break.
 
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