Camshaft Bevel Gear 28T

[SebringMike]

Hello All,
A few questions for the group...
a) are the camshaft bevel gears the same for all of the NC 250/350s? From what I can see, they are, and the original part number is 0400.29.030.
b) if yes, does anybody have a spare laying around?
c) or must the be replaced as a set (camshaft bevel gear and bevel w/shaft).
Thanks,
Mike

[DewCatTea-Bob]

[quote= SebringMike ...
" are the camshaft bevel gears the same for all of the NC 250/350s? From what I can see, they are,
or must the be replaced as a set (camshaft bevel gear and bevel w/shaft).


____ I believe a great number of them are indeed identical, and-thus could possibly be interchanged without consequence,, however I've discovered that a number of found examples are-not as perfectly matchable ! _ And due-to such disconcerted happenstance, it's of-course best to replace either b.gear-piece of a bevel-set with a 'matched-pairing', (which have most-usually been 'matched' by a trained factory-tech.worker).
While it's fairly likely that you-yourself may happen to find a couple of non-factory-matched bevel-gears that seem to mesh with one-another well enough,, before final installation together, they first ought-to be put-through a meshing-test similar to that which the factory would've done (had a factory-tech.worker happened to've been presented with the same pair of bevel-gears to check for matchability -[compatibility] [and possibly becoming a worthily 'matched-set'] ).
__ You may find more of related interest within the thread found at this link... viewtopic.php?f=3&t=1663


Hopeful-Cheers,
DCT-Bob

[SebringMike]

Thanks Bob for the comments and link.

With those in mind, I guess I need to change my question b) above to read...

b) does anybody have a matched pair of bevel gears for the camshaft and tower for a 350?

Thanks,
Mike

[DewCatTea-Bob]

[quote= SebringMike ...
" Thanks
for the
link. "

____ Did you come-across a post by me that tells how the factory processed the matching-up of bevel-gears ?
__ It's fairly possible that you could do about the same process to find-out if a randomly mated bevel pair sing together (or unfortunately rather growl).



" does anybody have a matched pair of bevel gears for the camshaft and tower for a 350? "

____ Note that a w-c.350 tower-shaft would be too-long for a n-c.350, and that the tower-shaft of a w-c.250 is the same as that of a n-c.350 !! _ So-thus (gathering that you're in need of an upper bevel-set for a n-c.Sebring-engine), then you ought only be searching for just bevel-sets which have a tower-shaft length that's of the particular length which has it's tip-end protruding-out past the base-end of the tower-housing/tube by near-about a quarter-inch.



____ Sort-of curious as to how you've come to find yourself with needing another camshaft bevel-gear... Has your original developed a chipped tooth, or worse ? _ And if-so, do you have any idea of how it happened ?


Hopeful-Cheers,
-Bob

[SebringMike]

Bob,
I found a bevel gear set from another 350 NC Sebring on Ebay, so I'm back in action.

The bike was used as a farm bike until it quit some time ago. Based on everything I've discovered in the tear down, the previous owners weren't aware of metric and/or left-handed threads. I'm sure all of the members of the forum have been there, and done that.. so I'm not telling you anything you haven't heard before. It's clear that the bike has had some abuse at the hands of several(?) shade-tree mechanics, and I've spent the last few months fixing threads, repairing damage to the cases, and removing broken bolts. All of the left-handed threads on the bike have been impossible to undo, despite the application of multiple cycles of hot and cold, and copious amounts of lubricant. I have not had any problem with right-handed threads, so it leads me to believe that the left-handed nuts have been over-tightened by previous mechanics.

In the process of removing the nut for the camshaft gear, a tooth broke off the gear. I don't know if the process of heat cycling caused it to fail (which doesn't really make sense considering it's likely been through it many times while running), or if I did something while undoing the nut. In short, it's failed because of something I've done, but I don't know what.

The tear-down is 100% complete. The cylinder was honed and the new piston purchased. All new bearings are on order and seals & gaskets are in hand. I'm waiting on the new bushing for the kick-starter to be made. It's taken me weeks to clean the old cow$hit, mud, grease and oil from the engine and frame, and I've commenced polishing everything that needs it. Once all the new parts are in my garage, I will begin the assembly of the motor.

Despite spending significantly more than my (naive) budget for the restoration, and making mistakes along the way, I'm having an immense amount of fun.

Regards,
Mike