Engine cuts out a running speed

Bobh651

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I gave a 2000 Seafarer and the engine cuts out like it’s in derate mode. If the engine stalls out I can restart it right away. Any idea on what would cause this?
 

seasick

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Depends on what motor and exact symptoms but my first guess would be a clogged VST filter. If not that, then another form of fuel starvation. Do you have a single motor or twins?
 

Bobh651

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I have a single engine. No alarms go off.
 

Parthery

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Is it an OX66? Does it die like someone turned the key off? Will it restart without issue after it sits for a few minutes?

If the answer was yes to these questions, check your fuel pump to see if it has power the next time it quits on you. If it doesn’t, your fuel pump relay is on its way out.
 

Bobh651

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Is it an OX66? Does it die like someone turned the key off? Will it restart without issue after it sits for a few minutes?

If the answer was yes to these questions, check your fuel pump to see if it has power the next time it quits on you. If it doesn’t, your fuel pump relay is on its way out.
It’s a SX200tXRY.
 

seasick

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Reading this again, It looks like the revs slow down but the motor doesn't stall ( you say it runs in 'derate' mode).
At that point did you turn off the ignition and try to restart.? Can you confirm that your engine alarm sounder works.
It will help to know if the engine just dies or instead slows down.
Also reconfirm that when it does whatever it does, you turned off the ignition and restarted the motor with no difficulty.

When you had the problem and restarted, did the problem reoccur after a period of time cruising?
 

Bobh651

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It runs at a reduced rpm than stalls out. If I wait a minute it starts right away.
 

Halfhitch

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Next time it goes into "reduced rpm mode", leave the throttle where it was before it slowed and have someone start pumping the primer bulb. If the engine comes back to life while pumping but dies away after a bit of not pumping, then it is likely a weak primary low pressure fuel pump that is bad. Needs to be replaced.
 

seasick

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Next time it goes into "reduced rpm mode", leave the throttle where it was before it slowed and have someone start pumping the primer bulb. If the engine comes back to life while pumping but dies away after a bit of not pumping, then it is likely a weak primary low pressure fuel pump that is bad. Needs to be replaced.
Take a look at the bulb to see if it has collapsed. That would indicate a blocked tank vent usually. Also when you squeeze it, see how it feels. It should get firm normally.