I honed the bores this morning and they cleaned up fine. I can see where the engine sat with the pistons 75% up the stroke and one valve was open so there is a little more corrosion at that spot but no ridge or pitting. Almost all the damage seems to have been done while it was sitting.
The rings, on the other hand, were stuck harder than anything I have ever seen before! I had to beak each ring into segments and then drive the pieces out with a skinny punch! After getting the rings out, I gave each a good wire-brushing and then chucked them in the lathe to clean up the ring grooves.
I checked my valves and they are all serviceable - not like new but good enough. Spent the rest of my shop time this morning cleaning up parts and scraping old gaskets off.
Dianne's C77
I throw gummed-up pistons in to my ultrasonic cleaning tank at around 60 deg C. That usually releases the rings and gets rid of most of the varnish. I can usually get the rings out intact.
Sound like you're having fun.....
G
Sound like you're having fun.....
G
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
Dianne
No the ultrasonic wouldn't have helped much in that case. The heat might have eased things a little though.
Sounds like you're getting stuck in .....
Yep, it's all about having fun, and learning a little. :-)
G
No the ultrasonic wouldn't have helped much in that case. The heat might have eased things a little though.
Sounds like you're getting stuck in .....
Yep, it's all about having fun, and learning a little. :-)
G
DianneB wrote:Is that what it is called? ;)G-Man wrote:Sound like you're having fun.....
It wasn't varnish on the rings - it was corrosion. Don't think ultrasonic would have done that. Don't matter anyway - it's done now.
Time to split the lower end and see what's wrong with the kick-start pawl.
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
While waiting for gaskets, oil seals, and piston rings, I split the case to diagnose the intermittent kick-starter problem.

I found the kick-start ratchet assembly in very good condition so it must have been the kick-starter gear not properly engaging with the transmission. I am going to have to read up on that to make sure everything is copacetic when I put it back together!
Time to start washing and cleaning parts to get everything ready to go back together (and HOPE I can remember how everything goes LOL!)



I found the kick-start ratchet assembly in very good condition so it must have been the kick-starter gear not properly engaging with the transmission. I am going to have to read up on that to make sure everything is copacetic when I put it back together!
Time to start washing and cleaning parts to get everything ready to go back together (and HOPE I can remember how everything goes LOL!)
Hi Dianne
What was the symptoms of your kickstarter problem? The gear that surrounds the ratchet is in constant engagement so you might need to look elsewhere. Have you looked at the kickstarter knuckle and how it grips the kickstarter shaft? The knuckles usually develop a crack over time and when the crack spreads under load it can open up the spline enough to slip.
I drill a hole at the end and weld up the crack.

The ratchet pawl might seem OK under hand force but could be slipping under full load. Has to be one or the other.....
G
What was the symptoms of your kickstarter problem? The gear that surrounds the ratchet is in constant engagement so you might need to look elsewhere. Have you looked at the kickstarter knuckle and how it grips the kickstarter shaft? The knuckles usually develop a crack over time and when the crack spreads under load it can open up the spline enough to slip.
I drill a hole at the end and weld up the crack.

The ratchet pawl might seem OK under hand force but could be slipping under full load. Has to be one or the other.....
G
DianneB wrote:While waiting for gaskets, oil seals, and piston rings, I split the case to diagnose the intermittent kick-starter problem.
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I found the kick-start ratchet assembly in very good condition so it must have been the kick-starter gear not properly engaging with the transmission. I am going to have to read up on that to make sure everything is copacetic when I put it back together!
Time to start washing and cleaning parts to get everything ready to go back together (and HOPE I can remember how everything goes LOL!)
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F
'61 CB72 '64 CB77 '65 CB160
'66 Matchless 350 '67 CL77
'67 S90 '77 CB400F