Topic: dropped nut in crankcase

[cj8990]

Doing my head gasket.. and I dropped a nut in the crankcase.  Tried using the magnet to get it but no luck and it's no where in sight.  I'm going to try taking the oil pan gasket off tomorrow but I wanted to ask how hard splitting the crankcase open was?  The motor is currently not on the bike so it's almost there.. and it seems as if the manual is making it out to be easier than it is.  Is it just..
-Oil pan bolts
-Handfull of crankcase bolts on top of motor
-Handfull of crankcase bolts on bottom of motor
-split case open

reassembly..
-no gasket between case.. RTV it
-bottom case bolts
-top case bolts
-oil pan gasket
-oil pan bolts
-finish head gasket
-party

Also any suggestions for turning the motor upside down without breaking the giant head studs poking out or should I just remove those as well?

Oh one more question.. All the head stud nuts came off except one.. on this one the whole stud came out.. Are O-rings supposed to go around these because I thought I saw O-rings around the other head studs?

thanks!
-Corey

[70CB750]

What bike?

If its CB750 there is a bolt under the starter, make sure you take it out too.

Get a flat box, draw an outline on it and stick bolts you take off in respective locations.   It will help you with the assembly.

On light 2 stroke bikes we would flip them upside down to get stuff out, but if the engine is already out, it will not take long.

Also oil pump has to be removed - at least for CB750.

[mystic_1]

You won't break the cylinder studs by turning the engine upside down.  Plenty of people flip the engine over and rest it on the studs, with no issue.  Put it on a piece of plywood or something, so you don't ding up the threads at the tips of the studs.

also +1 to the above flipping the motor around to see if you can get the nut to fall out. 

If you DO split the cases, Do NOT use any old RTV on the case halves.  Use Hondabond or Yamabond or a similar product specifically designed for this purpose, they are formulated to be "semi-drying" and designed not to shed pieces inside the motor if you get any excess squeeze-out (within reason, don't gob it on too thick).

mystic_1

[Garage_guy_chris]

I dropped a nut into my engine while i was building it back up. I couldnt find it anywhere so i used my fathers inspection camera and a magnetic pickup to retrieve it. Worked like a charm and saved splitting the cases again. It ended up being down right beside the oil pan flange.

[cj8990]

Thanks for the replies everyone.. sorry the bike is a 76 cb550.. It looks like rain today so I'll try the oil pan method later this week and hopefully that works.

Also does anyone know if there are o-rings around the studs?

-Corey

[Phinn]

I'd remove the oil pan. The nut will probably come out with it, but if it doesn't, I'd keep the engine right side up and use a magnetic pickup on the end of a gooseneck extender, to reach up and root around. I dropped a circlip after I'd already split and rejoined the case halves (twice), and didn't feel like doing it a third time. It was lurking under the crank.

If your bike is anything like the 750, the oil pan is huge and collects most dropped objects.

[przjohn]

As others have said remove the oil pan and turn the motor all around and it should come out. If not, and in fact even if it does, get a shop manual. Cheap dough for good know.