Changing crank seals on an RD-400

 

  My 77 RD-400 needs new crank seals. I have the factory service manual, but
its procedures assume a complete teardown is required, and goes into the
detail necessary to completely dissasemble engine & trans.

  I'm wondering if I can get by with substantially less dissasembly. Anyone
done one of these lately? Can I split the cases just by removing the bolts
in the bottom of the lower case? Any other advice for this project?
--
Lee K. Gleason N5ZMR
Control-G Consultants
lee.gleason@comcast.net

 

e:


It sounds like you're the guy with a manual and some tools that TOG
keeps warning us about...

Do actually think that you can pull the crankshaft and pistons out
through the bottom?

If you could, how would you ever get the piston rings back into the
cylinder bores without breaking them?

 



Yes, but it won't help.


Hand it over to someone who knows what they're doing, or have them
standing by.


--
BMW K1100LT  Ducati 750SS  Honda CB400F  Triumph Street Triple
Suzuki TS250ER GN250  Damn, back to six bikes!
Try Googling before asking a damn silly question.
chateau dot murray at idnet dot com

 

On Nov 15, 8:46 am, totallydeadmail...@yahoo.co.uk (The Older
Gentleman) wrote:

Having NOT torn down an RD I'll take for granted your advice is
better. 8^)

 

On Sat, 14 Nov 2009 15:58:53 -0600, "Lee K. Gleason"


Take the clutch cover off and remove the clutch. Behind it you will
find a flat ring that's attached to both the upper and lower cases
with three screws (this helps axially locate the transmission main
shaft bearing), once you remove it (and the alternator along with it's
cover, of course) you can split the cases. With both pistons at mid
stroke you can lift the crank enough to replace the seals. When you
drop the crank back in, make sure that the little locating  bumps on
the bearings are in the recesses machined for them in the cases along
the parting line.

This a quick and dirty (literally) way to do it, but I wouldn't
recommend it. You must clean all the adhesive off the mating surfaces
to insure a leak free assembly, if you don't you could have a lean
condition and a piston seizure as a result. This is difficult to do
with the transmission and crankshaft in place with a big possibility
of crud in both of them after you're finished with the assembly.

It doesn't take that long to do it right, these are hammer simple
engines to work on. Disassemble it completely, inspect everything as
long as you are in there and reassemble it clean, you'll be happier.
Doing it right once is much quicker than having to do it twice.

                                      Bill Smith