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Discussion Starter · #1 ·
so I'm about to pull the right side crankcase cover on my 1982 CB450SC to swap the clutch. I just popped over to the Honda dealer to get the gasket. They had one loose in a manila folder. It looked find so I bought it. I checked the fit on the cover I intend to use and it looks like its too big. I only have one dowle installed but if you look at the pic you can see all the bolt holes and off by a fair margin. Is this gasket just screwed or what? Or would it work?

20180118_104545.jpg
 

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That gasket looks like it has shrunk, probably a very old gasket.
You could soak it in oil and see what happens, or take it back to the dealer.
 
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It became distorted in the envelope, you should be able to use it by placing all the bolts in their holes to hold the gasket. This is a case where a little bit of sealer will come in handy to glue the gasket to the cover.
 

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Discussion Starter · #4 ·
I took a few bolts to peg it and it looks like it should line up well enough. I have black RTV on hand. Will that work or should I pick up something different? Just a thin bead between the gasket and cover and clean both case and cover surfaces as normal?
 

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Discussion Starter · #6 ·
I'll heed your advice, but what the problem with RTV? I would never use it for something like case halves but it's what's recommended a lot for sealing oil on my Jeep. I guess I sort of just answered my own question. If I wouldn't use it for case halves why would I use it here........ While were on the subject of seals and what not, what are the OEM o-rings for the balance shaft adjuster access port, dipstick and clutch arm. I have nitrile o-rings in the required sizes.
 

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I imagine it’s the same for 450s, but the concern with RTV and 360s is that it can smush out through the joins/seams and potentially block the small oil channels machined into the covers and along the case studs, feeding the head, and you then oil starve/fry your top end. It goes on in a thicker layer than Hondabond, which just goes on as a thin film.
 

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Most of the time we don't use RTV because most people use way to much. RTV will work fine if you plan on never getting the thing completely back off. A very LIGHT coating like just barely enough to hold it on will be fine.

I actually use axle grease to hold gaskets on. Allows them to slide around a bit while you tighten things down so they won't pinch or tear. They will also come back off cleanly when you pull the cover the next time and usually will be reusable.
 

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Very careful application of RTV can work, problem is that most people work from the principle of "if some is good more is better". It's not as much of a problem with the SOHC 400/450 engines because the oil pickup in the sump is quite large and well screened. A good gauge of whether too much was used is that when the parts are bolted together there's a bead of sealer squeezing out
 

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Discussion Starter · #10 ·
Well I've sourced some Gasgacinch locally and will be using that.
 

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Yes, people tend to use far too much rtv sealer which can block filter screens, oil ways and jets, not to mention threaded holes, which can cause the holes to "burst" !

DO NOT use rtv or any other sealer on a clutch cover that has an oil way or gallery !

Cannot seem to see the heat activated adhesive areas on that gasket.

I like to cyno a "new" gasket to the clutch cover, particularly around the thin walled oil pressure switch area, and allow it to dry completely before thinly greasing the unglued surface just before fitting.

This allows the "new" gasket and cover to be removed later without tearing, and allowing an oil leak free refit.

Saves some dollars and the time to make a "new" gasket.

ps, a little more "cleaning" needed and don't forget that tiny steel washer.
 

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Discussion Starter · #12 ·
NOT USING RTV.

I have and will use Edelbrock Gasgacinch as per LDRs advice to help hold the gasket in the proper place before bolting it all up.

I assume the washer you are referring to is the concave one under the clutch nut?

I like to cyno a "new" gasket
Huh?

That picture was taken right after I got the gasket and dug that cover out of storage. The right side cover I will be installing has been thoroughly cleaned inside and polished like a mirror on the outside. I also replace the the three O-rings and removed and blocked the tach drive with a block off and an o ring as I will not be going back to a mechanical tach. Hoping for once to have zero oil leaks.

This was all supposed to happen Tuesday but I somehow forgot about the issue with the 400 series clutch nut which is surprising being I did this whole thing two years ago. It wasn't long after I pulled the right cover from the old engine that I realized the clutch tool I have does not fit. Then it all came back about how I had used a drift and a hammer to remove and install the clutch nut last time. I didn't want to do that this time so I got a 15/16 socket and I am in the process of making the needed tool.

This OEM gasket also has no adhesive strips. But this OEM gasket DOES have them. Whats going on here guys?

Again, thank you guys for your endless insight and advice. If only every answer didn't bring with it three more questions.
 

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Discussion Starter · #14 ·
I used gasgacinch and massaged the gasket a little to line all the holes up. Easy peasy. No leaks.
 

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I’ll go with Frogman79 and say no to RTV, but use grease on the gasket first. If you’ve done the job right first time a gasket will seal and do its job.
I’ve used Blue Hylomar before; and I like it. A very thin film; think like nothing at all smear it with your fingers all over and then stick the gasket to your mating face.,
Having said that I just smear grease on the mating surfaces and do it up. It’s all in the preparation. A clean joint with the proper gaskets won’t leak.
 
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