I chilled the bearing outers in the fridge (avoided the freezer) and didn’t use any Loctite.Sounds like you need to remove the bearing outers again, double check for extreme cleanliness and try again to refit them following the advice already given.
Also, did you freeze the bearing outers? Some say this is the thing to do, but there’s a counter view which is that the frozen bearing will cause issues by sucking too much heat too fast out of the heated case and then expand rapidly, causing tightness before being fully seated. Heated cases and room temp bearing outers are my own preference.
And what about Kommandos loctite question? His reason for asking is that loctite can cause a bearing to tighten too much when it hardens. So, unless your bearing housing are suspect, best to avoid loctite and simply aim for scrupulous cleanliness IMHO.
The original (old) bearings do not show '3C' stamped. They do display: - 'FAG GERMANY F.D NU306E'. Plus, I originally checked the crank did have generous end float before I pulled the old bearings out.The old bearing was C3 marked and not tight? I've forgotten if these are replacement bearings or not!
As I say... the replacement bearings I recieved from RGM have... ‘FAG X-life NJ306-E-XL-M1 INDIA R059-163952’ but without the ‘3C’ endorsed. I'll give them a call.Looking at the 3C bearings that RGM sell, it should be very easy to tell if they are 3C or not...
View attachment 21224
Prior to the introduction of the ISO standards for rolling element bearing where the C was standardised you could see other forms of marking for bearing clearances.The original (old) bearings do not show '3C' stamped. They do display: - 'FAG GERMANY F.D NU306E'
Yes, I checked... no shims.Are you sure that there's no shim in either side of the cases?
Yes, they are being exchanged so no worries! Cheers.Echo what's stated by others, RGM sells both bearings, I had to return the non-C3's they sent me in exchange for the correct ones. Contact the vendor, they are easy enough to deal with and will exchange for you
UH oh!Likewise with the outer bearings to ensure the replacements were seated correctly at the bottom of each housing without any obstructions (like old shims)? – Yes and both went in smoothly after the casings were heated then driven down to the absolute bottom.
I can't see any evedance but then I'm no expert!How much evidence of the old bearing spinning in the bore? ( they always do)...
I saw no declaration of what NHT you are working on!
Thanks I suspected but had no way to confirm as muchthe old versions of C3 were 3 dots or 3 circles as it was by maker not a set standard.
I would not worry one bit at .009. Only if you are starting an engine from cold near or under 32f /0C, would I not like .005".My engine is on the bench now. Bolted up the cases with the crank and nothing else in, no case sealant,
Case bolts nipped up but not full torque.
I got 9 thou side play. 60F temp in the garage.
Think Norman White says 11 thou is what you want. I cannot worry about 2 thou the engine has done 10k with these
bearings no problems.
When hot the cases are only going to grow and more than the crank.
I bet that wasn’t the only thing that shrunk that morning.I would not worry one bit at .009. Only if you are starting an engine from cold near or under 32f /0C, would I not like .005".
Reminds me of one trip ( 70 commando roadster) where I left Watertown, NY at around 9PM and the town Bank thermometer read +3f . Cases would have shrunk for sure...
9PM is night and getting colder all the time. I only make 80-90 mile, out of approx 300 mile trip, and had to get a motel room. Most of it was NY thruway.I bet that wasn’t the only thing that shrunk that morning.