I Got Me a Mercury !!!

tpenfield

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The EVINRUDE is a smooth runner if in good condition.------One issue with them is a weak head gasket when new.-----Replacement gasket ( SIERRA ) is improved with metal rings.-----May need to adjust slow speed mixture.-----I own many of these 6 HP models ( 66 to 79 ) and they are fantastic motors.----Easy to find new / used parts for them.
Yes, I got my Johnson 4.5 HP sorted out a few years back, and I think this motor (Evinrude) will take the same. It did play a trick on me yesterday on the way out to the big boat. Crapped out from fuel starvation. Not sure what happened, but the fuel line lost its prime. It took some time to get the line re-primed. Meanwhile, as we were floating adrift in the harbor, the Admiral asked where is the paddle? . . . My response "back at the house . . . " :ROFLMAO:

I think the Evinrude may need some fuel pump maintenance.
 

tpenfield

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As for the Mercury . . . I came across a tidbit of info somewhere (can't quite recall) that these isolator blocks (basically non-conductive mounting studs for the maker points) can/do develop cracks which allow the spark to jump to the housing rather than the spark plug.
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I'm not sure if that is fact or theory, but these blocks have some cracks, so new ones are on order ($9 ea).
 

racerone

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Just solved an Evinrude 15 HP.-----Stalling repeatedly.------Before even looking at the motor I looked INSIDE the fuel tank.-----Pick-up hose on a cheap plastic tanh was loose and sucking air.----Easy fix.
 

tpenfield

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I ran the Evinrude some more today (with oars in hand) . . . definitely a fuel starvation issue. I brought the motor back to the house to run it in the test tank. I replaced sections of fuel line with clear lines so I could see what is going on.

Essentially, the fuel is draining back through the fuel pump and when you go to start(re-start) the motor crankcase pressure pushes the fuel further back down the fuel line. If the fuel pump & carb are well primed, it seems to work, but the fuel pump is not able to create much pressure.

Anyway . . . a new fuel pump is on order.

It will be a race to see which motor . . . the Merc or the Evinrude gets fixed first :ROFLMAO:
 

racerone

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About the only thing that can go wrong is the fuel pump diaphragm.----I have about 6 diaphragms on hand to repair that simple little pump.-----I would never buy a new big $$ pump.-----And no I would not use an " amazon special " on these wonderful motors.
 
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