I've seen a few posts about this on the forum, but never found a solution posted. I'm in the process of cleaning up and rebuilding a second CB360T engine to install into my new to me 360T and while cleaning up the case I noticed that the bushing rubber was a little cracked. As I was planning to do a parts order, I figured I'd attempt to remove the already damaged bushing. Assuming that this was one of the seals/bearings that was available to replace was my first mistake. I proceeded by heating the cover in hopes to expand the joint to release the seal and that didn't do anything. Followed up with heating the cover and freezing the sleeve with freeze spray didn't work either. Onto my final mistake, I didn't have a blind bushing puller on hand so I just made the mistake of trying to pop it out with some leverage... Again I did not this wasn't a part that Honda even offered or documented in their parts diagram until I got to the point the even more so damaged bushing was removed.
Has anyone found a replacement somewhere for these? I'd measure the specs if it was in spec to see what other replacements are out there, but I'm at a loss for the dimensions with what I pulled out. The center sleeve is fine, rubber was toast to begin with, but the outer sleeve is far from dimensionally correct/in one piece.
I've seen plenty of builds documented with powdercoated case covers, so it's obvious that people have removed these in the past successfully and/or found replacements to install after (per one post I saw here), but no one covers it.
I reached out to a few of the CB parts vendors over the past week with no success. One recommendation was to have one fabbed in a lathe using delrin, but based on delrin's properties, I'm not sure it's going to last or hold up as a high pressure seal/bearing surface inside of a crank case.
That is correct. I'm talking about the press fit high pressure oil seal 'bearing' that is located on the bottom part of the oil passage on the right cover.
Nope, part #7 is the kickstart shaft seal. This part itself does not have a Honda part number. Others have mentioned finding a replacement, but they don't mention where or how. I figure it's either they found the one they removed, or bought a replacement sidecover.
My bike is a '75 CB360T, but the spare engine I'm rebuilding is an earlier year, I think it's a '74. All of the engine covers of this model are the same for '74, '75, and '76 so all the diagrams and parts for these engines are pretty much identical minus the recall parts being standard on the '76 years (cam chain tensioner cap and the oil pickup for the oil pump.)
In the CMSNL diagram I've edited above, the part I'm talking about is circled in red.
To satisfy my own curiosity and using your pictures and the CMSNL view you have posted, and involving the CMSNL exploded view of the oil pump...
Your picture of the inside of the clutch cover, the lowest "cavity" is oil feed from pump, then the "bush hole" of interest, the the centrifugal oil filter feed hole, and finally the oil feed cavity to cam area and gearbox etc.. Is this correct so far ?
The idler gear between crank and oil pump, rides on a shaft that is "static" due to the peg seen on the shaft in the CMSNL part photo ?
Is this correct, AND is the shaft hollow all the way thru ?
The bush and oil seal in the clutch cover is involved with supporting the static shaft for the idler gear mentioned, also being supported "at its other end" by the engine casting ?
Last thing, the washer, spring and "sleeve thing", parts 3, 4 and five, are they involved with the centrifugal oil filter oil feed ?
Since the oil pump design is good, there will be an oil pressure releaf valve in the system somewhere, a controlled internal oil leakage...
Maybe this diagram I sketched up will answer most of your questions. Please disregard the yellow square as it was part of the image that I borrowed to throw this together.
In terms of the pressure relief for the oil, I believe the sprung assembly in the cover is part of that system. the cover itself has three passages, of which one is the output of the oil pump into the bushing/seal we are discussing. The other two passages are to the spring assembly (next path in line) and the feed that leads to other parts of the engine. Based on the fact that the oil pump pressure is linear to RPM, I'm guessing that the system bleeds off pressure by forcing oil through the galley that feeds the rest of the engine. At lower RPM the oil is split between feeding the other parts of the engine system and being fed into the centrifugal filter.
So the spring loaded affair is the oil pressure relief valve, I'm not sure where it goes but you have it in front of you, so you can suss out how it works/where it lives.
I can now see where the pegged idler gear shaft goes into the "engine", it does not rotate. The idler gear rotates on this shaft/tube. I assume there is an oil hole in it to lub the rotating idler gear.
The "bush" in the clutch cover is the "outer support" for the idler gear shaft, and an oil way, hence the need for a "rubber seal". That deal, is it a lip seal, I presume it may be. Of course it could just be an o ring.
The part itself is composed of three parts combine into one 'part'. The outer portion is a metal sleeve, with a rubber body in the middle, and then finally an inner metal sleeve. The outer sleeve is what retains the part in the cover as it is press fit. The inner sleeve is just there to support the idler gear shaft.
As for a lathe, I do not have one. I know someone who does, but I'm not even sure where to begin on materials to complete this. One vendor I reached out to about this mentioned using delrin as the material and machine it to fit. Per my understanding of material science, delrin isn't ideal for the environment this would be housed in due to temperatures. It would happily deal with the oil, but the temps are where it would start to degrade and cause failure.
Ideally, this should be a part that I could just source somewhere. Honda might not have it listed as a part, but there has to be some company out there making these bushing seals that would fit.
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