No gasket between fuel pump cover and carburator

I discovered a leakage in the front carb. It is leaking in the red circel. (see attachment)
I opened it up and discovered there is no gasket, only a rubber ring. Is this correct? In the yamaha exploded drawings i cannot see this part of the carb opened up, so i assume it is identical to the rear carb?
Shouldnt there be a number 14 in between of the coverplate and the carb? (see second attachment)
 

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This is the part opened up. Again, only rubber ring, no gasket. I dont know if thats correct.
It started leaking once the engine was at operating temperature. Begin of the day it runned fine.
 

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JetManiac

Stoked
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orlando
This is the part opened up. Again, only rubber ring, no gasket. I dont know if thats correct.
It started leaking once the engine was at operating temperature. Begin of the day it runned fine.
There are several reasons we find for this leak. If a non-OEM Oring is used, then leaks can happen due to inferior rubber and out of spec sizing.
Also we have found some covers not flat, and needed to be decked/lapped true. Finally, it can be hard to tighten the oem bolts, we switch to allens to be able to easily tighten well and even. We have an allen bolt kit for this reason. Pressure testing dual 38 carbs to just under the popoff is critical for finding leaks.
 

john zigler

Vendor Account
Location
wisconsin
There are several reasons we find for this leak. If a non-OEM Oring is used, then leaks can happen due to inferior rubber and out of spec sizing.
Also we have found some covers not flat, and needed to be decked/lapped true. Finally, it can be hard to tighten the oem bolts, we switch to allens to be able to easily tighten well and even. We have an allen bolt kit for this reason. Pressure testing dual 38 carbs to just under the popoff is critical for finding leaks.

This and more commonly for us, we find problems to gaskets, diaphragms, o-rings, etc due to use of ethanol fuel.
 
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