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Discussion Starter · #1 ·
So, I purchased my CB360 in the middle of March. Ever since, I've been wrestling with various issues that have prevented me from enjoying it. First electrical, then mechanical, I've replaced: tires, rectifier, battery, spark advancer, oil pump, handlebars and various other cosmetic items, and now the entire top half of the engine. I've redone timing a total of 5 times, adjusted valve clearences 3 times, and adjusted my cam chain tension 4 times. In addition, I've pulled my lower back twice, and sustained a multitude of cuts and bruises. I've almost sold it, almost taken a BFH to it, and almost killed it (lack of oil).

But as of today, the time, money and frustration has paid off. I owe the majority of my happiness to this board. The wealth of information and tight knit brotherhood of parts sharing has single-handedly saved this old bike from the scrap heap.

Fast forward to last night. I dissassembled the head that Jayel sent me, and thorougly cleaned it. Afterwards, I took a can of engine degreaser, and stopped by the local car wash and blasted the casting with pressurized water. It looked beautiful. I then brought it home and coated it with a light oil, before individually cleaning and lubricating the entire valve train. Re-installation was a real bitch, because the fingers of my automotive valve spring compressor wouldn't clear the inside of the head. I ended up using a piece of the fragged oil pump to act as a spacer between the compressor and the valve hat. An hour later, I was done, and dead tired.

This morning I got an early start (9:30), and began the teardown. The day was not without causualty, and my first problem of the day was getting the tach drive cable out. The old one wouldn't budge, and I quickly rounded out the head of the bolt. I got handy and used an screw extracter, which promptly snapped off in the head which prevented me from drilling it out. In a last ditch effort, I grabbed my hacksaw and cut the cable off to get clearence for the last head cover bolt. What I found when I got the cover off was astonishing. The amount of wear and damage to the inside of the head was staggering. The good news was that the cylinder linings still looked like glass.



It had gotten so hot at one point, that there were chunks of melted aluminum in the journals. When installing the new head, I hit my second snag. One of the allignment guides which fit between the head and cylinders went missing, so I ended up going into work and fabbing one out of 1/2" SS tubing. It worked like a charm, but set me back a good hour. The rest was pretty straightforward, but the results were the stuff of dreams.

After not running for over a week, the slightest touch of the starter button charged the engine to life and it immidietly settled down to one of the most beautiful idles I've ever heard out of a carburated bike. As I let it warm up and put the seat back on, I checked for leaks, and there were none. Not only did it run perfectly, it also sounded about 10 times quieter than I've ever heard it. A quick test ride yielded terrific results. It ran smooth and strong. Absolutely perfect. No stuttering, dying, bad idle, or hiccups of any kind.

After almost 3 months and countless headaches, it's finally fixed, and it runs like brand new.

A last thanks to all you guys for forcing me to do the right thing, and keeping me motivated to fix this old girl. I couldn't be happier.

-MK
 

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Kudos to you sir :D Dont be a stranger now that you finished your project....
 

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Discussion Starter · #3 ·
Believe you me, this project is far from over. In fact it's now where I wanted it to be when I bought it.

Now I can begin the fun stuff...

-MK
 

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that type of failure is caused by poor oil maintenance, I bet that poor engine didn't know what a oil change was, 1000 miles at the most on these for oil change and cam chain adjustment.....
I think you can save that cam shaft for show and tell, it's a wonder the engine even ran before
 

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Sounds like you got it...BUT..... That camshaft shows failure from lack of oiling, both on the journals and the cam lobes..... I hope your new pump is working, but it couldn't have been this bad when you re-assembled it the last time (was it?)..... I have seen that much damage from only a few (under 15) minutes of running un-oiled....
You DID fill the splash-baths for the lobes with oil before putting the top cover on didn't you?
And you DID make sure the passages from the new pump were clearall the way to the top end?... I have seen a small "glob" of silicone sealant on the base gasket close off the passage with similar results......
Visual inspection through an open valve adjustment cover while running will verify good oiling up top....... (messy, but maybe necessary)
 

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Discussion Starter · #6 ·
I did make sure the oil passages were unobstructed, and fill the oil baths. I'll pop the tapper covers next time I run it. Although I can say that the engine runs super quiet now.
 

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:!:
 

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:!:
 

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Discussion Starter · #11 ·
What amazes me is that the hardened steel camshaft has much more wear than the soft aluminum casting. A metrologist at work, told me that in this situation the softer material will actually cause the harder material to wear quicker. Didn't make sense to me at the time, but it's hard to deny what I found!

As for maintenance logs, I bought a Moleskine when I bought this bike, which I have recorded every thought, change, purchase, and development in.

-MK

Here's a little pic from yesterday after a nice ride. One of these days I'm going to go for a ride with my SLR and take some really good pictures...
 

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The way it was explained to me that a hardened part can wear more than a soft part that it is running in is that if there is contamination in the oil that is abrasive it gets imbedded in the soft material and wears away at the harder material. Just like a grinding wheel.
Don
 

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Perhaps the softer alloy transfers its heat away better than the hard steel, which got so hot it started to destruct?
 

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Discussion Starter · #14 ·
The aluminum head looks like it got so hot that it started to melt a little. Although I highly doubt it got to the required 1200F to actually melt the aluminum. What's more likely is that the aluminum started to peel away a little, and balled up in the journals, acting like a lathe on the camshaft...
 

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That has to be hands down the worst cam shaft i have EVAR seen!

Nice to hear a 360 finally running around here.

Maybe i can possibly have the same results next week. Be even sweeter if i got a good head to bump the compression up 20psi.
 
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