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b61 40hp top end

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smokinone

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i have a 61 40hp evinrude . wa

i have a 61 40hp evinrude . was just dealer serviced with a tune up . just got it in the water for the first time this year . i found that im down about 8 or 9 mph. last year i was able to get up to between 25 - 30 mph . now i'm lucky if i can get 20 on smooth water . is there anything i myself can do to get a bit more speed . besides repowering with a bigger engine .

please help

tim
 
"Tim, something else to check

"Tim, something else to check - the pin may have been moved that selects your tilt position.

If your bow is "lower" than it was it will be ploughing water and will shave a good bit off your speed."
 
"Tim, It sounds like you are

"Tim, It sounds like you are running on one cylinder, or you have no compression on one cylinder. I recommend you check spark on both and then check compression on both."
 
i do have good compression on

i do have good compression on the engine . how do i check the spark ? weight is the same as last year . pin is in the same position ?

tim
 
disconnect both spark plug wir

disconnect both spark plug wires and insert a screwdriver that fits and holds on the coil inside on each one at a time. Remember you need to disconnect both to avoid engine start. Put screwdriver shaft near a ground so the distance is about 1/4 inch or 7/16 to be more accurate and do not hold with your hand. Crank engine and check for spark lightning.
 
"a good ground will be a screw

"a good ground will be a screw head of the powerhead, those that are around the housing where the spark plugs are fitted."
 
pulled the plugs today . top r

pulled the plugs today . top ruuning ok botoom plug fouled up . could this be the problem ? i think i'm running too rich . have to wait until tomorrow to check the spark . found a bit of oil around threads of plug . does any one know the proper posittioning for the rich/lean srew or is it determined by the motor ?

tim
 
"do you have screws with a spr

"do you have screws with a spring outside the carburetor? if not, your carbs have fixed needles like mine, sparks are ok on both cylinders? are the carb throttles synchronized? carb cleaning done?"
 
will check today for the screw

will check today for the screws . as well as the spark . carb was rebuilt by an auto mechanic friend of mine . not a clue of what you mean by carb throttles synchronized ?

tim
 
"pulled the wires and plugs to

"pulled the wires and plugs today . checked spark on wires . good . checked spark on upper plug , good . checked spark on lower plug , week . checkedupper plug with lower wire , good . compression : 98 top , 95 lower . faulty plug ? removed both plugs , cleaned , checked gap at 30 .still have old plugs if i need to change out on the water . tomorrow will be the test . still want to know proper setting for rich lean screw .

tim"
 
"carb synchronization refers t

"carb synchronization refers to the opening and closing on both throttles. They should move equally , if one moves 4mm to say a example, the other should move 4mm too. Check the spring thing..."
 
"Whaler, a 61 40hp only has on

"Whaler, a 61 40hp only has one throttle!!!! Tim if you have a weak spark on one cylinder have that resolved.The spark should jump a gap of 1/4" or better on both cylinders. If it does not jump that gap you essentially have no spark when the air is compressed to 100PSI"
 
"sorry not-a-student, if I off

"sorry not-a-student, if I offended someone, I was thinking because mine has 2 carbs, this 61 engine was similar, I always learn something new which makes me a permament student, again sorry!!!!!!!"
 
"well , removed plugs cleaned

"well , removed plugs cleaned and regapped . reinstalled . took the boat and launched this morning . didn't any speed at all . might have gotten to 10 mph . turned around and headed back to the ramp . top speed going back ranged between 2 -10 mph .#&%$#& . tired of all this crap . just want to do some fishing . time to repower i think. anybody have any other suggestions ?


tim"
 
"how much money do you spent o

"how much money do you spent on that engine? if not much, go for a later engine."
 
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