340 Kawasaki - Some important questions

[scorp11]

I was trying to just put seals in the bottom half by splitting the case halves, putting the seals in and re-sealing the case. Was hoping to take finish it up tonight, but ran into some unexpected things.

First. Why are there o-rings around all the bearings ? What purpose do they serve ? Pretty much all of the ones on the one out of our spitfire are pretty hard, and some are split. Considering there is a groove at the crankcase centerline, I can't see how they seal anything. Do they need to be soft and one piece ? Can I use some case sealer to fill in the split part ?

Second. The center seal on this one feels a lot looser than I expected. I did have this thing running before I tore it apart and it did seem to idle ok. I imagine if it were bad, I would need a new crank. Do these seal under crankcase pressure ? Please tell me they do

I read through the service manual and it doesn't seem to talk about this. Check end play and make sure the center seal is lined up is about all I see.

Finally, I assume it is safe to wipe some case sealer all the way around the outside of the center seal ?

Thanks in advance for all the help.
Kevin

[tmartin]

The orings on the bearings themselves act as a vibration/ noise dampener. The two on the center seal are important. The center seal block does fit loosely and seals with the fuel/oil and pressure in the case. I would recommend getting new orings. They are a 62 mm oring that bombadier used and may still use. I found some at john deere that they matched by size. They do stretch over the crank without having to press it appart but the pistons have to be off the rods. As for the case halves Three Bond 1197. Put it on each half an bolt it together and you should have no trouble. If you get new orings you should not have to put sealer on that center seal. Anerobic sealer also works. hope this helps

[Invader440]

You can also still get them from Arctic Cat under part number 3001-437. Also helps to soak them in hot water for a little bit before putting them on. As far as a sealer for the case, personally I prefer Permatex part 2B but I've been using this for years working on cars.