74 550 crankshaft seal replacement questions

[wingrider]

Hello All,

A while back I picked up a 74 550 project, had a fairly rough life. I want to resto-mod it, and plan to put a newer swing arm, and newer forks on it.

I know that the seals are probably shot on the crank...a leak down test was done by the fella I bought it from, and it wouldn’t hold pressure.

Fast forward to now. I had picked up most if not all gaskets, seals, and O rings to tear down the engine, pull the crank out, and get it fixed right when I bought the bike.

Now that we have moved to our new house, which we built this past summer, I will finally be able to start working on my new shop.

Being I am in the frozen tundra where it is colder outside than the inside of my freezer, we are mostly stuck indoors. Cruising around on YouTube, I happened to watch Alan Millyard rebuild a Kawasaki 500 triple crank in his workshop.

This got me thinking...could I rebuild the 550’s crank in the shop as well? I have a press, but certainly do not want to jump in here, and find that I can’t finish it. Bill Bune is about an hour away from me...I know I could bring to him, and it would get done right, but at this moment, I have more time than money...

What say you all about this crazy idea of mine?

Thanks for any help!

[daxman]

hmm, good question and probably one only you can really answer..

You sound confident yet cautious though which must be the right combination. Millyard is a terrific engineer, one of a kind, but he does make things look easy.. one strike of his copper mallet and it runs true
I know very little about this but you will need some measuring tools - v blocks and a dial gauge minimally I guess, although I think I seen someone measure run-out using a lathe. If you have tools, time and inclination then why not?

[Mitch466]

I also have 2 gt 550s, a gt380, and a gt185 and I intend on replacing crank seals/ rebuild the cranks in the near future. It would be great if you could maybe post some progress photos and maybe some tips. It seems as if the triples are really going to be difficult, and yes, the master Millyard, and with the magic of television ( or internet) makes that 500 kawi crank seal replacement look very easy. Please keep us updated !

[jabcb]

Service bulletin Specification-7 has the crank specs: http://www.ozebook.com/compendium/techb ... %206-9.pdf

Its useful to have the lower crankcase half cleaned & prepped so that you can use it for test fitting.