When removing the reed valve assembly on a 9.9 do you need to replace the gasket or apply sealant

[909]

When reassembling ? Motor is a 1999 9.9 Yamaha MSHX .

I want to convert the 9.9 to a 15 by expanding the reed valve limiter spacing from 1.5 mm to 6mm and also by removing the rev limiter .

Anyone familiar with 9.9's ?

 

[909]

Here is a discussion about the mod on the Yamaha forums:

how do i convert my yamaha 9.9hp to 15hp - Yamaha Outboard Parts Forum

Ask the experts on our Yamaha Outboard Forum for repair issues, diagnosing problems, links to diagrams, suggestions on buying parts and more. They can answer questions for any Yamaha outboard model or horsepower.

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[909]

Here's a picture of the reed valve assembly removed

Note the black sealant. Also note the left side is the 9.9 side unmodified 1.5 mm. The right side is the modified 15 side 6 mm.

 

[909]

Bump

 

[99yam40]

try to reuse it and see, I would
not sure how much a new seal would cost you tho on something that old

 

[909]

You're probably right. It's old and will likely tear. What kind of sealant is this.

 

[99yam40]

service manual should have that info
My C40 does not have that type of gasket so my manual does not show any sealent in that area