Camshaft lateral movment??

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jug

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Finally getting my engine back together after a long down time using JS goodies. Cam, lightweight lifters etc,etc.
I have a question for you gurus. How much lateral movement should there be on the camshaft. The cam lobes are centered perfectly with the lifters.
This is using the provided shim on the inner side of the cam bush (see pics) but even with the cam sprocket snugged down the camshaft can move inboard about 3mm till the cam sprocket bottoms.
. The cases are 71-72 with the breather mounted to the rear lower drive side case (big alloy breather) with non- shouldered cam bushes.
Thanks for any advice in advance.
JUG
Camshaft lateral movment??


Camshaft lateral movment??


Camshaft lateral movment??
 
Finally getting my engine back together after a long down time using JS goodies. Cam, lightweight lifters etc,etc.
I have a question for you gurus. How much lateral movement should there be on the camshaft. The cam lobes are centered perfectly with the lifters.
This is using the



provided shim

With the cam, do you mean?



The cases are 71-72

72/73 I assume.

with the breather mounted to the rear lower drive side case (big alloy breather) with non- shouldered cam bushes.


Were the original tabbed thrust washers in place at the time of dis-assembly?
 
I have a JS2 cam in my race motor, the beveled washer is installed on the cam inside of TS casing and the provided shim is between the outside of the TS case and the inside back of cam sprocket . It is a pisser to get right, as it tends to slip off the outside of the cam bush boss.
I stick it on during assembly.
My cam end float is no more than 0.010"
Jim has this shim instruction in his supplied notes for his cams.
Regards Mike
 
NorComCycles said:
Finally getting my engine back together after a long down time using JS goodies. Cam, lightweight lifters etc,etc.
I have a question for you gurus. How much lateral movement should there be on the camshaft. The cam lobes are centered perfectly with the lifters.
This is using the



provided shim

With the cam, do you mean?
yes the cam lobes and the lifter lobes/feet are pretty much perfectly aligned.



The cases are 71-72

72/73 I assume.

with the breather mounted to the rear lower drive side case (big alloy breather) with non- shouldered cam bushes.
Yes 72/73, the cam bushes are not shouldered.


Were the original tabbed thrust washers in place at the time of dis-assembly?
No, this engine is going back together with a later nos set of cases. If there are additional washers, can you give me a part # ? And where is it positioned.
Thankyou for the help.
jug
 
Brooking 850 said:
I have a JS2 cam in my race motor, the beveled washer is installed on the cam inside of TS casing and the provided shim is between the outside of the TS case and the inside back of cam sprocket . It is a pisser to get right, as it tends to slip off the outside of the cam bush boss.
I stick it on during assembly.
My cam end float is no more than 0.010"
Jim has this shim instruction in his supplied notes for his cams.
Regards Mike
Hi buddy,
According to Jims instructions the shim can go either inside or out side the case, depending on where you get the best alignment on the lobes.
Mine has best alignment on the inside of the case, pretty much spot on. The problem is on the outside between the non shouldered bush and the cam sprocket.
I may be missing a washer, these are later cases as my old cases are grenade -ed My old cases had a shoulder on the bush on the inside and protruded slightly on the outside. These later cases the bush have no shoulder and are pretty much flush with the case.
JUG
Camshaft lateral movment??

Camshaft lateral movment??
 
I did a bit of cyber surfing and found this. On Freds site, OLD BRITS
06-2600 -- NORTON, Bush, Cam, 1972/73 750, L.H. & R.H. This is the only bushing that has oil channels in the bushing and is to be used with the cam shafts that do not have any oil scrolling on the bearing journals .
06-3020 -- NORTON, Bush, Cam, 1973/74 850 R.H. This bushing can be used with any scrolled cam in any crank case with the tachometer drive mounted in the timing side crank case.

My cases have scrolled bushes for non scrolled cam. Looks like I may need to change the bushes. I notice these bushes are shouldered and are slightly longer, protruding past the case on the outside.
Camshaft lateral movment??

Any advice greatly appreciated.
jug
 
Were the original tabbed thrust washers in place at the time of dis-assembly?[/quote]
No, this engine is going back together with a later nos set of cases. If there are additional washers, can you give me a part # ? And where is it positioned.

06.2601 tabbed washer, one either side. There is often concern expressed regarding the tab breaking off.

An option, in the case of a non scrolled cam, is to replace the shoulder-less timing side bush with 06.3020 (it is necessary to oil groove the bush).

With a scrolled cam, it is possible to use the MK 3 bushes, 06.5428 x 2.
 
NorComCycles said:
Were the original tabbed thrust washers in place at the time of dis-assembly?
No, this engine is going back together with a later nos set of cases. If there are additional washers, can you give me a part # ? And where is it positioned.

06.2601 tabbed washer, one either side. There is often concern expressed regarding the tab breaking off.

An option, in the case of a non scrolled cam, is to replace the shoulder-less timing side bush with 06.3020 (it is necessary to oil groove the bush).

With a scrolled cam, it is possible to use the MK 3 bushes, 06.5428 x 2.[/quote]

Thanks for the reply.
Regarding this...
With a scrolled cam, it is possible to use the MK 3 bushes, 06.5428 x 2
Does that mean 2 bushes, one pressed in from the cam side of the timing case half and one pressed in on the sprocket side. (I have scrolled cam)?
What to do about the bush on the drive side case half?
Remember the bushes that are now fitted (came with the cases)are scrolled bushes.
Just trying to get my head around it all. :)
JUG
 
Thanks for the reply.
Regarding this...
With a scrolled cam, it is possible to use the MK 3 bushes, 06.5428 x 2




Does that mean 2 bushes,

Yes


one pressed in from the cam side of the timing case half and one pressed in on the sprocket side.

Yes.



(I have scrolled cam)?


If you have a scrolled cam to use, that is definitely an option.


What to do about the bush on the drive side case half?
Remember the bushes that are now fitted are scrolled bushes.

Personally, I never hesitate to replace cam bushes as part of a major rebuild. I especially like the end play control of the shouldered MK 3 timing side bushes.

If the bushes are perfect, and it is just a refresh, then fine, there is a strong case for leaving them as is. If it is a rebuild with "all the good bits", which is what you are pursuing, it is difficult to understand why the old bushes would be left (even more so if the cam is scrolled, and the bushes were intended for a non scrolled cam). As in, do the whole job, surely.

I have seen numerous instances where worn cam bushes that obviously should have been replaced, but were not, as it was apparently too difficult for the owner to either do, or to get the job done.

I am not a fan of the earlier spilt type bushes (just my personal preference).
 
These are NOS cases, and never been together. The scrolled bushes are new, installed from factory. I have no problem getting them replaced. In fact prefer to. Just want to know what is best to replace them with, Both timing side and drive side. And how to get them out, especially the drive side.
Timing side looks pretty straight forward, the drive side looks like its gunna be a bitch.
BTW, thanks for your help :)

JUG .
 
A washer in that position is ugly engineering, floating around on the cam, any washer should really be in a fixed position,idealy find a flanged cam bush that eliminates the washer from that position
 
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