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Discussion Starter · #1 ·
Hey all,

This is a cross-post from my project log.

I am taking apart my top end (hopefully stopping there) as part of a clean-up and tune up of my engine, which was an oily pig. Valve head was removed and cylinders are left on the bike. Head gasket looked like it was in good shape, but the Hondabond sealer I used previously must have been misapplied because I found it EVERYWHERE inside the valve head and valve head cover except on the seating surface. It will be a matter of peeling that crap off slowly and surely to make sure both parts are cleaned.

Cam chain guide and cam chain tensioner look good and no noticeable wear from the last time they were inspected, so I will reuse those components.

Question time:

1. As I was manhandling the engine pulling things apart and rotating it on my workbench, the cylinders were loosened from their seating on the lower gasket and I had some oil weep out. Is this gasket still OK to be reused, or do I need to pull the cylinder, free the pistons, and replace the gasket with a fresh one? If so, I have never gone that far before, so I will have a lot more questions!



2. Early in the start of this year's project, I spent time on CMC making a "shopping list" of upgrades and replacement components. I saw the $200 re-surfacing option of camshaft and rocker arms. In comparing my set with the examples in the CMC video on this service that they offer, it appears that mine are generally OK, but not great. Do you think I am OK reusing them as is, or would it be of value to re-surface them?






Thanks!
 

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Discussion Starter · #2 ·
Well I did some sleuthing, and it looks like I will have to go ahead and pull the cylinder off, replace the gasket, throw on some new rings, and get the cylinder honed.
 

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Discussion Starter · #3 ·
Last night, I pulled off the cylinders, labeled and visually inspected the pistons and rings. Base gasket has seen better days.

1. Once the piston clips were removed, the piston wrist pins were pretty stubborn to remove! I had to tap them out with a soft punch and a hammer!

2. Both pistons had this wear mark on the surface on each face (as shown in photo below and 180 degrees on the other end). Is this normal?

 

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Discussion Starter · #4 · (Edited)
OK so summary of questions so far:
1. Would it be of value to get the camshaft and rocker arms refinished based on the condition above?
2. Should I replace the piston pins? Or can they be reused? When I tapped them out, they had a little wear mark from where they interfaced with the connecting rod ends, but overall looked OK
3. Is the piston wear shown above OK or should I be concerned?
4. (NEW) After reading some other threads, I figure I might as well replace my cam chain at this point! I am interested in doing it without splitting the cases. Can anyone walk me through how you popped out a link on the old chain, connected the new chain, and fed it through? I am thinking of buying the following replacement cam chain (http://www.common-motor.com/honda-360-cam-chain), has anyone had experience using this? I saw in an unrelated thread on this forum that the CMC cam chain that a forum member used was actually incorrect.
 

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1. The cam looks OK to me. I don't see any obvious signs of gouging. Those rockers look like a couple have some scoring or gouges. Truth be told you can probably buy a good used one off flea bay a lot cheaper than having them resurfaced. I just bought 4 a month or so ago for less than $30.
2. Per the manual inspect them for their wear limits. If they are within wear limits and don't have any visual defects you can use them again.
3. It sure looks bad. But I don't have enough experience to judge what is going on there. Again the manuals have very clear instructions on wear limits. The answer is to use an appropriate caliper to measure them and see if they are within wear limits. If so you can reuse them.
4. You can replace the cam chain without splitting cases if you get a timing chain with a a rivetable link. And if you have a chain riveter. You do NOT want to use a timing chain that has a master link. That is a recipe for disaster. My advice is if you already have the engine this far apart you might as well split the cases. And use a closed timing chain. If you have gouges on the rockers you must have some metal or debris floating around int he engine and its probably in your oil pan. I'd split the cases and thoroughly clean everything. I say this from my own experience. You have to ask yourself how many times do you want to take this thing apart?

Other things to consider is did this engine get the tensioner recall done? If not you may want to replace that as well. Also there was an improved oil pickup screen you can get that allows the oil sump to pick up oil even if the bike is leaned over to the left on the kickstand or when leaning hard into a left turn. These engines are notorious for oil starvation issues on the top end. And they also don't particularly like loose metal debris int eh engine aprticularly in the cam bearing surfaces.
 

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Discussion Starter · #6 ·
Sounds good misterguitar. I will inspect everything thoroughly. Yes I should clarify that I ordered a cam chain with a rivetable link, not one with a clip-style master link. When I sent the engine to a mechanic a while back, he replaced the cam chain tensioner and slipper to the correct kind (I gave him a NOS one that incorporates the post-recall design). I will compare the specs of that (now-used) one to ensure that I am in spec still.

In other developments, as I was rotating the engine around the workbench, I found the following washer lying nearby. I slapped myself since I am meticulous about labeling and packaging everyhing. I looked through the parts diagrams in the CB360 Manual, and did not see this size washer in any of the diagrams. Can anyone ID this?!?! I am going insane trying to figure out where it goes. The only home for it that seemed to work is the oil pump idle gear shaft, but that already had its proper washer installed.



 

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Discussion Starter · #7 ·
I went on CMSNL.com and searched for "WASHER" under CB360TK0 and looked through 10 pages of washers. None matched. I am going to say that washer finding at my workstation was a random accident.
 

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Discussion Starter · #8 ·
Looks like I am dealing with some piston slap, which shows in the wear on the pistons themselves. I am taking the cylinder in to a machine shop for cleaning and measurement hopefully this weekend. Based on this wear I am seeing, I may have to consider the possibility that I may have to bore out some.
 

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Discussion Starter · #11 ·
Well I guess that settles that.
 

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That washer goes on the end of the oil pickup . It fits to the pipe end that goes to the oil pump. It's not an actual part but tends to fall off this part sometimes. there is a rubber oring that goes on between it and the engine.
 

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Hello Krukster. I noticed this and another thread of yours and had a few questions. Since you are nearby and are rebuilding your engine I wondered if I could stop by and view your progress and/or help out at times. The other item is the first thing that caught my eye - your trouble with leaking oil behind the points cover. I recently inherited a load of problems due to my daughter buying a '74 360 that was "in excellent running condition" in June. I am contemplating at least an upper engine rebuild this winter due to low compression and seeping oil.
 

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Discussion Starter · #15 ·
Hello Krukster. I noticed this and another thread of yours and had a few questions. Since you are nearby and are rebuilding your engine I wondered if I could stop by and view your progress and/or help out at times. The other item is the first thing that caught my eye - your trouble with leaking oil behind the points cover. I recently inherited a load of problems due to my daughter buying a '74 360 that was "in excellent running condition" in June. I am contemplating at least an upper engine rebuild this winter due to low compression and seeping oil.
I will send you a PM shortly.
 

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Discussion Starter · #16 ·
Update from my project logs:
Bleh! I got a call from the machine shop with my cylinders. I definitely had some piston slap which explained the wear on the piston sleeves. The cylinders were way too out of round beyond spec so I am going to have to go to 0.25 overbore. Luckily I have a set of 0.25 ART pistons and corresponding rings handy!
 

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Camshaft shows tappet clearances have been all over the place, too loose and too tight.
There should be an area at base of cam without any witness marks (the area where you have rockers rubbing)
The witness marks on pistons would be fine if cylinders are round, did you get the actual numbers?
It's very rare that cylinders are worn until you get up around 70~80,000 miles, usually rings go first and bike smokes
 

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'Witness marks' are area's where moving parts contact leaving scuffs or scratches
 

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Discussion Starter · #20 ·
Camshaft shows tappet clearances have been all over the place, too loose and too tight.
There should be an area at base of cam without any witness marks (the area where you have rockers rubbing)
The witness marks on pistons would be fine if cylinders are round, did you get the actual numbers?
It's very rare that cylinders are worn until you get up around 70~80,000 miles, usually rings go first and bike smokes
Unfortunately no, I have not been able to get the exact numbers from the machine shop. Are you suggesting that they might be scamming me for extra work? A rebuild of the top end was previously performed for me in 2009(?) by a garage mechanic. I am skeptical of his work now as I have seen piston rings installed upside down...

In regards to the camshaft, I took a look at it again more closely and I have seen rubbing marks at where the lobes taper down, and "not shiny" at the circular part of each cam. Is this in re-usable condition, or would you recommend that I get it restored? The $200 charge at CMC is a bit rich for my blood right now, but if I must, I will.
 
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