Help & Analysis: 1988 Johnson 6 HP 2 Stroke

bnelson12

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Dec 30, 2021
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As an update for the group as well, thank you for all your input. I decided to order a new impeller kit, as well as a new thermostat
 

Crosbyman

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oozing fuel-oil is what we are talking about.... just unburnt fuel just wipe it off it will eventually stop if only from self sealing itself as crud accumulates in the joint .

did you do search to learn about sludge....
 

bnelson12

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Dec 30, 2021
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oozing fuel-oil is what we are talking about.... just unburnt fuel just wipe it off it will eventually stop if only from self sealing itself as crud accumulates in the joint .

did you do search to learn about sludge....
I did. I didn't realize that older 2 strokes naturally do it. one thing I read up on too is that for a lot of these older johnsons, if you just let them idle while you have them running in a bucket, the motor is running high enough or hot enough to burn all of the oil in the mixture, therefore there is excess. When I'm running this on the laker at higher throttle and harder, there shouldn't be nearly as much. does that align with your knowledge?
 

racerone

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Dec 28, 2013
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Oh so many people are unfamiliar with a 2 stroke engine.-------Fact-----When piston is near / at bottom of the cylinder the fresh air / fuel charge is pushed into the cylinder.----But the exhaust ports are open and some fresh fuel and oil are pushed right out the exhaust as piston moves up.-----Only on NEWER 2 strokes that are computer controlled and fuel injected is this different.
 

tphoyt

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Jun 10, 2010
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Yes the theory is the higher rpms would burn more efficiently and a create less pollution. The unburned fuel and oil in the older 2 cycle motors is for the most part the reason they are banned from use in smaller bodies of water.
Just out of curiosity how much oil are you adding to your fuel. As in how many ounces per gallon of gas?
 

Crosbyman

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just to compare a non smoking/oily 75hp ETEC will burn about a 2cups/hour (.6ltr/h) trollling... my kicker a 9.5hp from 1966.... very likely more !
 

racerone

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Dec 28, 2013
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A conventional 2 stroke does not NEED TO BURN OIL to run.----But it is something that happens.-----Oil is mixed with gasoline to provide lubrication to the spinning / moving parts.------Consider that the E-TEC and others actually run like a 4 stroke for part of the cycle.----The air is compressed in the cylinder and only gasoline is injected into the cylinder.---Same as what happens in a 4 stroke.----Done with the help of a computer.----Same computer controls injection of oil to spinning / moving parts of the motor.---
 
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