Primary o-ring

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gortnipper

gortnipper

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I bought a new oring and installed it today as the one I had wasnt sealing properly.

This one must be larger diameter than any I have ever seen, as there is .065 gap between the case and cover when the bolt is snugged down to 25 lbs.

Thoughts on this?

Primary o-ring
 
New rubber gasket will do that, over time it will sqush down and be a thinner gap, if it don't leak no problems.

Ashley
 
Agree with if it doesnt leak all is well and agree with that the gap lessens over time and with tightening.
 
To fill the groove takes a 0.192" cord.... a AN cord is around 0.228" so not accounting for the rubber composition that is around 0.055" gap not including compression. :D

A 0.020" gap might be a little more in the ball park.

Primary o-ring
 
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I've seen that gap on a few Commandos over the years. No harm as far as I know, since the outer cover supports no components inside the case.
 
Installed a new inner primary case and gasket from AN a few weeks ago during the gearbox bearing replacement. A large gap resulted here as well. No leaks. :)

~998cc
 
Been buying and using expanded foam rubber by the meter for a few years now, doesn't seem to leak and I end up with in effect a face to face joint, which i think reduces the chance of distortion. Those o rings always seem way to hard to me for 1 central clamping nut.
 
Myford said:
Been buying and using expanded foam rubber by the meter for a few years now, doesn't seem to leak and I end up with in effect a face to face joint, which i think reduces the chance of distortion. Those o rings always seem way to hard to me for 1 central clamping nut.
Click to expand...
more details on they make and model of the expanded foam rubber you are using please
 
There was a post a few weeks back where someone mentioned windshield washer hose of suitable diameter works well for this seal. Just use a bit of rtv at the two ends, leaving the join at top of casing.
 
Tornado said:
There was a post a few weeks back where someone mentioned windshield washer hose of suitable diameter works well for this seal. Just use a bit of rtv at the two ends, leaving the join at top of casing.
Click to expand...

1/8" hose size fits the inner case groove nicely, no sealant/glue required.
 
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