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Engine Strip and Gasket Replacement

Started by bennylepa · 2 replies · 2062 views

bennylepaStandard MemberPosts: 98
Joined: Jun 2010
Engine Strip and Gasket Replacement
I have had a very subtle oil leak from one of my gaskets, the one down the centre of the engine, crankcase???, but this has become a steady drip now so has taken me off the road. I intend to take the engine off the bike this weekend, strip it down and rebuild it with all new gaskets. I am quite looking forward to it as I haven't done something like this before and also love working on my bike. I do however have a few questions and want to be well prepared for this task.

Is this a relatively simple job, how long should it take?
Do I need any special tools to do it?
Does anyone have instructions on how to do this.

Your experiences and knowledge would be appriciated.

Cheers
Ben
WaynusModeratorPosts: 1108
Joined: Feb 2009
Re: Engine Strip and Gasket Replacement
All gaskets are pretty easy to replace, except for the center gasket between both crankcases.
In order to do so, you first have to remove the top end. (replace afterwards: head gasket, cilinder gasket, 3 cylinder head gaskets, 3 rubber rings, stud rings (4), copper washer)
Check the distribution chain and sprockets as well.
Then, remove the clutch cover. Make sure to clean the 2 filters (centrifugal in the clutch + the one on th ebottom of the crankcase) and check the clutch plates (replace afterwards: clutch case gasket, clutch plate gasket, 2 oil pump gaskets + O-ring around the kick shaft)
Remove the clutch, (oil pump removal is recommended), the shift system and the big sprockets.
Lay the engine on the ignition side to make sure the gears stay in their place.

Check everyting for wear or dirt, and replace the gaskets. Make sure to mount everything correctly.

While removing the gaskets, make sure you remove all rubber rings as well + exhaust gasket + carb gaskets + the washers under the oil drain & distribution bolt.

Special tools you'll need:
- flywheel puller (to replace the 2 rubber o-rings under the stator plate + the hbig one in the center)
- special tool for clutch removal (or you could try the screwdriver / hammer / Jeremy Clarkson method)
- impact screwdriver (not necessary but will come in handy while removing the clutch plate)

If this is your first time, you'll need anything between a couple of hours and a whole day.
keep in mind you might have to start over to alter some things a couple of times...
Get yourself a good service manual, or at least good exploded views, or take pictures of every single little bolt, nut, washer, ring,...

Once started, I can give you advice on most of the problems you'll encounter.
Good luck!
bennylepaStandard MemberPosts: 98
Joined: Jun 2010
Re: Engine Strip and Gasket Replacement
Thanks for the reply Waynus. I am ordering the bits I need tomorrow so will hopefully be able to start on the weekend. I have some nice exploded diagrams and am going to do as you say, take lots of pictures and mark stuff as I take it off.

This may not be the last your hear from me on this issue and your help is very much appreciated, as always.

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