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35 HP Mercury O/B

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oldboaterbob

New member
I bought a Merc 35 hp & am not sure of the age SN # A712716 which ran great although was a bit hard to start but ran & started easily once warmed up then all of a sudden lost power far out came in on own power at full throttle running very slow died once throttle idled down.Could this be a carb problem as I see a lot of powdered foam & dirt around entrance of carb? Thanks for any info..oh yes sparking fine on both cyl's.
 
Does the inside of the cowling have a foam liner ?---Any pieces of a liner missing?---------Possible that debris is holding a reed valve open.
 
racerone said:
Does the inside of the cowling have a foam liner ?---Any pieces of a liner missing?---------Possible that debris is holding a reed valve open.
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Yes I noticed there was a foam liner around the emerg cord that powered and I believe most likely got sucked in it so I took all the foam off and guess it should all be taken off & cleaned.Hopefully this will solve the problem.Thanks for such a quick response.
 
That's a 1986 Canadian built Merc twin that was produced between 1984 and 1989 - nice little motor but I was never fussy about the carb on this model.

It used a relatively "old" side bowl back draft Tillotson carb.

There is a decent "repair kit" from Merc (about 30 bucks) and if you don't know much of the history of this motor, it's worth a carb rebuild. Tillotson parts are getting scarce so it's worth doing the carb while you still can get the kit - then with care it should be fine for many years to come.

I would be inclined to do the impeller (maybe a water pump kit, but only if it really needs it - 80'ish bucks), change the gear oil and the sparkplugs (NGK BUHW surface gap plugs are the current spec - replaced the Champion L78V's (original) - NGK's work better with the ignition).
 
galamb said:
That's a 1986 Canadian built Merc twin that was produced between 1984 and 1989 - nice little motor but I was never fussy about the carb on this model.

It used a relatively "old" side bowl back draft Tillotson carb.

There is a decent "repair kit" from Merc (about 30 bucks) and if you don't know much of the history of this motor, it's worth a carb rebuild. Tillotson parts are getting scarce so it's worth doing the carb while you still can get the kit - then with care it should be fine for many years to come.

I would be inclined to do the impeller (maybe a water pump kit, but only if it really needs it - 80'ish bucks), change the gear oil and the sparkplugs (NGK BUHW surface gap plugs are the current spec - replaced the Champion L78V's (original) - NGK's work better with the ignition).
Click to expand...

I thought it was in the 80's and it is in very nice condition other than this problem so I do believe I will get the rebuild kit as I intend on keeping it.It pumps very strong so I will keep my eye on it for possibly one more season but will replace the plugs/gear oil although they are very clean.I was told by the guy I bought it from just across town that he bought it from the marina & has been serviced from them since new (the dealer sticker is still on it).I would like to thankyou for your much needed info.
 
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