Merc 25 HP A741456 Canada Reed seal issue

w2much

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Spent some time figuring this one out. Hot spark jumping half inch, soaked and rebuilt the carburetor but still a no start..I knew there was a fuel delivery problem just not certain why. Error in rebuild rechecked and all that. So I pulled the reed cover off and found my issue. The seal had turned to gum. I will need to replace it. I was wondering if Canadian motors were not constructed to withstand the deteriorating effect of ethanol or if they are the same as American built motors ? The motor is a 1989. I would think that rubber seal from then would be resistant to such deterioration. . The reeds as well as the crackcase are covered with the gummy residue of the old seal.. I can see it has entered the innards of the engine. I plan to replace the seal and put the motor back into operation. I am curious if that gunk will dissolve , burn and exit the exhaust? I will clean up what I can but I am not keen on opening up the block. Your thoughts ? Thank you in advance.
 

GA_Boater

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I seriously doubt Canada or US or ethanol has anything to do with your melted seal. Ethanol usually affects rubber that soaks in gas - Hoses, fuel pumps and carbs. Look at a parts list for motor and compare the part number of the US version.

Was it was running fine and all of a sudden it started acting up? Or did you pick up the motor like this and it may have been overheated causing the the seal to fail?
 

racerone

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?----But the seal on the reed cage is a rubber type product and it is exposed to fuel.
 

GA_Boater

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?----But the seal on the reed cage is a rubber type product and it is exposed to fuel.

It doesn't soak in fuel. That's why I said hoses, carbs and fuel pumps that soak. The interior of the motor has a fuel/air mix and mostly air, not 100% fuel like the hoses, carbs and pumps.

Have you seen this before, Racer?
 

w2much

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I would not think it was an issue of Made in Canada vs Made in USA as much as whether Canada uses ethanol or not.Not knowing the true history of the motor I was just wondering if it held up in its earlier life, perhaps in Canada, using non ethanol fuel then came to the US ( CA.)and started using our blended fuel which accelerated the deterioration. The seal is soft and gooey, slimmey and sticky to the touch. It has been in storage for about three years I was told. Perhaps the previous owner tried to start it and sprayed some nasty starter or cleaner through the carburetor. I do not know that it overheated or not and yes, this is the way it came to me. I was told it was a running engine before storage. When I picked up the motor it was stored prop exhaust to the floor laying down, not upright. Maybe it was stored with the carb bowls full and they slowly leaked down through the reeds onto the seal, just a thought.
 

racerone

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Is it the factory original seal ?----Or something else ?-----------Started a chainsaw one day, it ran fine after sitting for many years.-----Next day it started and then quit.-----Found the line from tank to the carburetor totally melted by today's fuel.----Replaced it and it has run fine since.----That bit of fuel line appeared to suffer after one day with modern fuel.
 

w2much

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I would guess it to be original. I agree with what you are saying. Thanks.
 
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