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Re-start fuel bogging at higher elevations-1989 Evinrude 150hp

Lindy

New member
Hello, 2 parts. 1. just bought a boat with a 1989 150 hp xp and after re-starting it boggs down and cannot accelerate. Also assume last owner used ethanol fuel. I’d assume the carbs are the issue? Any quick fixes/adjustmentsor shall I pull each carb? It also runs very rich and unsure if related. 2. Want to run the engine out of fuel during winter/ low use. Can I put an inline valve on near where the gas line enters the body to cut off fuel? Thanks
 
Hello, 2 parts. 1. just bought a boat with a 1989 150 hp xp and after re-starting it boggs down and cannot accelerate. Also assume last owner used ethanol fuel. I’d assume the carbs are the issue? Any quick fixes/adjustmentsor shall I pull each carb? It also runs very rich and unsure if related. 2. Want to run the engine out of fuel during winter/ low use. Can I put an inline valve on near where the gas line enters the body to cut off fuel? Thanks
Bogging and wet plugs can be caused by blow-by in the rings (hence the compression test), weak spark, incorrect spark plugs, or a carb flooding the cylinder.

As Racer said, verify the compression with an accurate gauge.
Use an air gap tester and confirm the spark on each cylinder with jump a 7/16" gap
Make sure you have a good set of Champion QL77JC4 spark plugs gapped at 0.030"
Make sure all passages in the carbs are clean and the floats are properly set.

One last thing, has this boat always been used at high elevation or did you buy it elsewhere and now use it at high elevation. In the past OMC offered high elevation kits for outboards that included smaller carb jets to compensate for the less dense air. I don't know if one of these kits was offered for your particular engine, but it's worth investigating.
 
Bogging and wet plugs can be caused by blow-by in the rings (hence the compression test), weak spark, incorrect spark plugs, or a carb flooding the cylinder.

As Racer said, verify the compression with an accurate gauge.
Use an air gap tester and confirm the spark on each cylinder with jump a 7/16" gap
Make sure you have a good set of Champion QL77JC4 spark plugs gapped at 0.030"
Make sure all passages in the carbs are clean and the floats are properly set.

One last thing, has this boat always been used at high elevation or did you buy it elsewhere and now use it at high elevation. In the past OMC offered high elevation kits for outboards that included smaller carb jets to compensate for the less dense air. I don't know if one of these kits was offered for your particular engine, but it's worth investigating.
Thanks for this info, and I'll check w/air gap. Sparks plugs and gap confirmed and brand new.
I bought this as used at about a 1500ft elevation, and I am now at 4500 ft. I've seen and will look into the high-elev. jets. I have a suspicion most of this is within the carburetors.
 
Check to see if spark will jump a gap of 7/16".----Note---The sparkplugs have nothing to do with that test !----The jets ( orifice plugs ) are easy to remove from the carburetors.-----Post the numbers you find on the high and low speed jets.---No need to remove carburetors to get those numbers.
 
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