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Discussion Starter · #1 ·
I just got the camshaft holder off to replace the gasket that I thought was leaking. Turns out it may be the orings on the bottom of the holder. The manual shows only one, bike bandit none, and I can darn near positive that I see two, one flat and one round. Anyone know what size or part numbers these are.
 

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The Oring has the following part number : O-RING (13.6X2.4) 91301-268-020



Download the partslist manual / maintenance manual from the following site : http://drop.io/CX500_GL500



See page 9 from the partslist manual





Pim
 

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Discussion Starter · #3 ·
I'm starting to get upset with this darn camshaft holder. I got the new gasket from Dan Topping and replaced the o-rings and put it back together only for it to leak worse than before. Took it all down again and the lower oring was leaking. I replaced it again and it held while idling, but something has let loose again after a high boost test run. I used a light coat of gasket sealer on the copper gasket, should I be applying it around the bottom of the cam holder where the gasket does not reach? I blew a whole weekend doing this twice and I am not looking forward to a third.
 

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I will give that a shot. Thanks for the suggestion.


The main problem with the stock o-ring in the turbos is it flattens out really quickly, especially if you get a new old stock o-ring- it could be 10-15 years old. Oversized o-rings still flatten out, but as they are crushed, they completely fill the gap.

I have used this method on other oil sealing o-rings as well.



You may also want to look for burrs, cracks, or chips in the area that could be scoring the o-ring, or preventing a good seal.



As a last resort with a stock sized o-ring, you could apply a thin layer of Hondabond sealer around the o-ring.

If you choose to do this, make absolutely sure that the surfaces are absolutely free of oil, and let the Hondabond dry for 48 hours before firing up the engine. If the Hondabond is even a little bit tacky before you fire the bike up, this method will fail.
 

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Discussion Starter · #9 ·
Tried the sealer on the o-ring the last time and let it sit for 36 hours. I just got a bunch of over size o-rings and will try again. I'll be able to do this blind folded by the time it gets fixed.
 

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Tried the sealer on the o-ring the last time and let it sit for 36 hours. I just got a bunch of over size o-rings and will try again. I'll be able to do this blind folded by the time it gets fixed.
The main problem with that "O" ring is that Honda got the cross-section dimension WRONG. When you measure the "pocket" that the "O" ring sits in, it is very nearly the same depth that the "O" ring is in cross-section.

They FORGOT that there was a gasket thickness to add to the "O" ring's cross-section dimension, for the assembly to work.

As someone else has said, go to the next larger cross-section "O" ring - at least 0.5mm larger. Most of those camshaft-holder gaskets are 0.4mm thick.

This was posted by me on the Oz BB about 4 years ago - we had a few cases of the same leak, and I had to do that job for at least four other guy's bikes.
 

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The upsize O-ring was the ticket. Thanks for the help all. So far about 150 leak free miles
So, are you going to keep the Turbo and bring it to the Spring Ride next year? We haven't had a Turbo yet.



R
 

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Discussion Starter · #14 ·
Bike is still for sale as are my spare parts. I will do a proper for sale post when I get decent pictures of everything. I will ride it until it sells or gets too cold. If I still have it in the spring I would love to attend the ride.
 
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