250 primary gears.

[DewCatTea-Bob]

" As the gears show play for 3/4 of rotation then a tight spot i'm looking for bent shafts etc "

____ So as it turns-out now,, then previously, I should've assumed that you had been indeed referring the crankshaft-gear after-all, when you stated "3/4 of rotation". ...
I had (wrongly) assumed that you had been referring to the clutch-basket/gear, which is why I had figured that one of it's two support-bearings had gone-bad.
__ Now that you've clarified that it's the crankshaft-gear that's been wobbling, I would now figure that one of the crankshaft's 2 support/main-bearings has gone-bad (instead), before I'd start thinking that the pinion-gear's end of the crankshaft has gotten bent, (so long as you still don't see any sign that the primary-gears have eaten something through/between them).
____ If you had noticed signs of the issue before removing the primary-gear/left-motor cover, then the bearing within that cover (which supports the left tip-end of the crankshaft), should be checked-out & replaced as well.
__ Looks like you're looking at a crankcase splitting-job, in any case, (sorry to say!). _ So when that job gets done, you might as well go-ahead & replace all bearings within the cases, whether they seem to be good or not.
____ BTW, I myself have never thought of doing the test which you came-up with - (removing the pinion-gear key, etc.), for trouble-shooting towards the root-cause of your issue.
Good thinking !


Hopeful-Cheers,
-Bob

[Bevel bob]

Hi bob, I'm not really very clever, I spent age's twiddling gears before the penny dropped,if the mains were worn i dont think the gears would tighten(too tight to turn by hand!), no its the muppets that rebuilt the crank last time, I could have done better myself.Do you think its worth dynamic balancing? I'm running the rocker clearance at 6 thou in and 8 thou ex ,Dont have any info on this cam or widecase books.

[DewCatTea-Bob]

" if the mains were worn i dont think the gears would tighten(too tight to turn by hand!), no its the muppets that rebuilt the crank last time, "

____ Right, I wasn't really realizing that your motor had been gone-thru so thoroughly & recently. _ And also, I wasn't suggesting that both main-bearings were merely "worn", but rather that just one of them had gone-bad -(broke-down somewhat), in order to cause such a wobble.
__ But now that I am realizing that your motor was completely rebuilt to such a full degree, I now rather suspect that the crankshaft was not properly 'trued', before then being installed into the main-cases.


" Do you think its worth dynamic balancing? "

____ Sorry, I really don't consider myself knowledgeable enough about that, to offer advice on it.
I know that there are those (who know more than I do about such balancing), who also claim that such single-throw crankshaft-assemblies can be 'balanced', (as if such a crank can either be balanced or, left unbalanced). _ But my understanding is that ya can only choose a percentage or ratio, of balancing - (between up_&_down, and, back_&_fourth), for single-throw crank.assemblies. _ And with that then being the case, then altering the currently-existing balance, thus means robbing-Peter-to-pay-Paul -(so-to-speak). _ So I guess if you don't have a specific RPM-range which you wish to smooth-out (in exchange for increased vibration within another range), then it's not really worth having the balance-ratio redone, (in my non-expert opinion).
__ Hopefully Eldert, (or some other expert type), has an informed opinion on this subject. _ And if so, I'd sure like to see a posting on what's exactly known about it !

" I'm running the rocker clearance at 6 thou in and 8 thou ex "

____ With the G&W-cam, I'd shoot for .0040" on the intake-valve, and .0050" on the exhaust-valve, (+/- .0005" for either). _ I've adjusted them so many times that I don't really recall the exact factory-spec.settings.
Anybody out-there got the actual valve-clearance settings handy?

UPDATE: I've since looked-up the valve-clearance setting given within a 350-SCR owner's manual... It simply stated ".10mm",
so I'd recommend that ya go for the settings I've stated above.


DUKE-Cheers,
-Bob

[Bevel bob]

Just to close this thread off, crank trued ,gears now fine,cam found to be std Mach 1 -Mark3.